ERNEST A. LACHN

and ROBERT E. JENKIN,

Systematic^, Distribution,

: and Evolution of the 1

Nocomis biguttatus

Species Group (Family

Cyprinidae: Pisces) with

' a Description of a

r

 New Species from

the Ozark Upland i

SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY NUMBER 91
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SMITHSONIAN CONTRIBUTIONS TO

ZOOLOGY

NUMBER 91

Ernest A. Lachner Systematics, Distribution,

and Robert E. Jenkins IT ? I j_ • r. i

J

 and Evolution of the

Nocomis biguttatus

Species Group (Family

Cyprinidae: Pisces) with

a Description of a

New Species from

the Ozark Upland

SMITHSONIAN INSTITUTION PRESS

CITY OF WASHINGTON

1971
ABSTRAC T

Lachner, Ernest A., and Robert E. Jenkins. Systematics, Distribution, and Evolution of the

Nocomis biguttatus Species Group (Family Cyprinidae: Pisces), with a Description of a

New Species from the Ozark Upland. Smithsonian Contributions to Zoology, number 91,

28 pages, 1971.—This study treats the three allopatric species of the Nocomis biguttatus group:

N. biguttatus, N. effusus, and N. asper, a new species. The systematics, distribution, ecology,

evolution, and zoogeography of the species are compared. The region of the Ozark upland is

emphasized because it is inhabited by the new species. N. asper is distinguished from N. biguttatus

mainly in having a characteristic tuberculation pattern present on the body of the adults which

never appears on the latter species. N. asper differs from N. effusus primarily in having two rows

of pharyngeal teeth compared to one row in the latter, and in having about one fourth of its

tuberculate body scales bearing two or more tubercles compared with only 3 percent bearing two

tubercles in the latter species. The coloration of the nuptial males of the three species differs.

Nocomis biguttatus is a wide-ranging form found naturally in the Missouri, upper

Mississippi, northern Ohio, and the Great Lakes drainages. It avoids the nonglaciated regions

of the upper Mississippi and Ohio drainages. This species is restricted to a few scattered populations in the middle and lower Missouri drainage—evidence of a once more widely distributed

species that has been largely extirpated from this drainage mainly by the erosional history of

the area, increased agricultural practices, and by droughts. N. asper and N. effusus have restricted

distributions on opposite sides of the Mississippi Valley. N. asper is contained chiefly in the

Ozark upland of the Arkansas River drainage of the tri-state area of Arkansas, Oklahoma, and

Missouri, with probable isolated populations in the upper Neosho system of Kansas and in the

Arkansas drainage of central Oklahoma, and a well-established population in the Blue River

system, Red drainage, of south-central Oklahoma. Such isolated populations also are regarded

as evidence of a wider distribution of these species in these drainages in the past. The disjunct

populations of N. asper are paralleled closely by the occurrence of isolated populations of

Notropis pilsbryi in the Arkansas River and Red River drainages. N. effusus is confined in the

southwestern Ohio River basin to the Duck River system of the lower Tennessee drainage, the

lower and middle Cumberland River drainage below its falls, and in the upper Green River

drainage.

The species of the biguttatus group chiefly inhabit tributaries and avoid the main rivers.

Clear-water streams, small-to-moderate in size, with low-to-moderate gradients, and with clean

substrates of gravel, rubble, and some sand, provide the preferred ecological requirements.

Generally, the preferred streams have a moderate balance of riffles and pools. Turbid or silt-laden

waters are avoided.

The Nocomis biguttatus species group is considered to be the most primitive group within

the genus; this assumption is based mainly on the generalized pattern of tuberculation on the

head and on the presence of two rows of pharyngeal teeth. The primitive condition persists in

N. biguttatus. The body tuberculation in N. asper and N. effusus (absent in N. biguttatus)

demonstrates evolution of another type of tubercle pattern in Nocomis. The reduction in the

number of tubercles per scale, the reduction in the distribution of tuberculate body scales, and

the increase in the size of tubercles on the scales of the body of N. effusus are regarded as

specialized conditions and correlate with the evolutionary trends of head tubercle development

in the two other species groups of Nocomis.

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in the Institution's annual report, Smithsonian Year.

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Contents

Page

Introduction 1

Acknowledgments 2

Methods and Materials 2

Nocomis biguttatus Species Group 2

Key to the Species of the Nocomis biguttatus Species Group 3

Nocomis asper, new species 3

Nocomis biguttatus (Kirtland) 10

Comparsion of Species in the Biguttatus Group 15

Distribution and Ecology 19

Evolution and Zoogeography 21

Literature Cited 24

Index 27

Ernest A. Lachner

and Robert E. Jenkins

Systematics, Distribution,

and Evolution of the

Nocomis biguttatus

Species Group (Family

Cyprinidae: Pisces) with

a Description of a

New Species from

the Ozark Upland

Introduction

Studies over the past several years have revealed a new

species of the Nocomis biguttatus species group in the

Arkansas River drainage. The new species is related

to N. effusus Lachner and Jenkins (1967) in body

tuberculation, and to N. biguttatus (Kirtland) in its

pharyngeal dentition. One problem of concern to us

was the possibility of the existence of intergrading populations in adjacent drainages north of the Arkansas

River drainage, such as the White River. We attempted

to obtain representative series of chubs from drainages

where existing museum collections were inadequate. A

survey of systematic characters in the wide-ranging N.

biguttatus was initiated. A factor complicating the

study was the need for nuptial male specimens in order

to ascertain the extent of body tubercle development—

a critical diagnostic character. Body tuberculation is

completely developed only in the mature males. The

large chubs are difficult to capture with conventional

small seines. They are captured best by angling and by

using an electric shocker.

Ernest A. Lachner, Division of Fishes, Department of Vertebrate Zoology, National Museum of Natural History,

Smithsonian Institution, Washington, D.C. 20560. Robert E.

Jenkins, Roanoke College, Salem, Virginia 24153.

In the Nocomis biguttatus species group, as with all

other species of Nocomis, tuberculation is an important evolutionary character. In two species of the N.

biguttatus species group, however, nuptial tubercles

not only develop on the head but are uniquely present

on the body. The head tuberculation, in regard to

tubercle numbers, size, and occurrence, is similar in all

three species of the biguttatus group (in contrast to a

great amount of interspecific differentiation in the N.

micropogon species group and the iV. leptocephalus

species group).

The Nocomis biguttatus species group was described

and compared with the two other Nocomis species

groups by Lachner and Jenkins (1967; 1971). The

objectives of this paper are to describe a new species

of Nocomis and to compare the three species of the

biguttatus group in respect to their systematics, distribution, ecology, and evolution.

The nominal species Nocomis biguttatus (Kirtland)

was described briefly in 1840 from Yellow Creek,

Mahoning River, Ohio. Lachner and Jenkins (1967)

described the second member of the species group, N.

effusus, from the Cumberland, Green, and lower Tennessee drainages. The systematic characters of these

two species were treated in detail by Lachner and

Jenkins, and their distribution and evolution were dis1
SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

cussed with particular emphasis on the occurrence of

members of the genus in the southwestern Ohio River

basin.

author received support from National Science Foundation Grant No. 23395 to Edward C. Raney, Cornell

University.

Acknowledgments

We are deeply appreciative of the efforts of many

individuals who freely loaned collections in their care,

provided data concerning the collections, and made

space and facilities available to us. Our special thanks

go to George A. Moore, Oklahoma State University

(OSUMZ) for providing the holotype and life-color

observations of the new species, and to Kirk Strawn,

Texas A. and M. University, for providing an excellent

series of tuberculate adult paratypes and other specimens, some of which he hand carried to Washington

from Arkansas after several successful attempts at pole

fishing.

Material was examined or data received from the

following individuals or institutions: Edward C.

Raney, Cornell University (CU) ; Frank B. Cross,

University of Kansas (KU); William L. Pflieger, Missouri Conservation Department; William M. Palmer,

North Carolina State Museum (NCSM); Royal D.

Suttkus, Tulane University (TU) ; Carter R. Gilbert,

University of Florida (UF); William M. Clay, University of Louisville (UL); Reeve M. Bailey and Robert Rush Miller, University of Michigan (UMMZ);

Old Indiana University Collection at University of

Michigan, UMMZ (IU) ; Carl D. Riggs and L. C. Hill,

University of Oklahoma (UOMZ) ; National Museum

of Natural History, Washington, D.C. (USNM);

James E. Bohlke, Academy of Natural Sciences, Philadelphia (ANSP) ; George C. Becker, Wisconsin State

University (WSU) ; D. E. McAllister, National

Museum of Canada (NMC); W. B. Scott, Royal

Ontario Museum (ROM).

The illustrative materials were done by supported

individuals or divisions of the Smithsonian Institution,

as follows: Carolyn Bartlett Gast and A. M. Awl,

detailed drawings; Gertrude H. Nicholson, scatter

diagrams; Dorothy L. Hubbs and Martin L. Wiley,

maps, X-rays, and technical assistance; Richard H.

Goodyear, computer operation and analysis; and the

Photographic Services Division.

The first author received support from the Smithsonian Institution Research Foundation; the second

Methods and Materials

The methods and techniques employed in this study

are the same as those given by Lachner and Jenkins

(1967; 1971). All body length measurements refer to

standard length (SL) in millimeters (mm) unless

stated otherwise. Abbreviations are spelled out when

used for the first time in the text. The institutional

abbreviations used in the sections on "specimens

studied" are defined in the section "Acknowledgments" ; for example, National Museum of Natural

History, Washington, D.C. (USNM).

The number of body scales bearing tubercles were

counted on the left side from tuberculate or tuberclescarred males. The body tubercles are discernible as

spots on larger females and nonbreeding males, but

tubercles in this state of development are difficult to

see and to count accurately. Many of our specimens had

some discernible body tubercle-spot development, but

these data were not used in our tabular comparisons.

Only collections containing tuberculate specimens

from the Arkansas River drainage are designated as

type materials. The number of specimens (in parentheses) and their size range is listed in the data for

the type material. The number of specimens only is

given for the nontype materials. The collections are arranged and grouped by basin, drainage, and state.

The collections plotted on the distribution map for

Nocomis biguttatus include all material examined and

data from reliable published accounts of major state or

regional surveys. Collections occurring together or in

nearby areas were indicated by one plot on the distribution map. The primary synonymy is listed; also

included are those references where examination was

made of the authors' original material and of material

that had some particular bearing on this study.

Nocomis biguttatus Species Group

The following characters best describe this group:

head with many moderate-size, nuptial tubercles extending from mid-snout to occiput; tubercles absent on

lachrymal; tubercles present laterally on body in two
NUMBER 91

species, and arranged in rows; head tubercles usually

antrorse; nuptial crest absent; red postocular spot present in life; dark caudal spot in young and in juveniles

large, round, and distinct; pharyngeal dentition 1,4^,1

to 4-4; scales small, about 31 to 38 in circumferential

series.

Key to the Species of the Nocomis biguttatus Species Group

1. Nuptial tubercles or tubercle spots absent on body; pharyngeal teeth number 1,4—4,1,

occasionally lacking a tooth on minor row of one side. North-central United States, from

Missouri River and Mississippi River drainages to northern Ohio River and Great Lakes

drainages Hornyhead chub, Nocomis biguttatus (Kirtland)

Nuptial tubercles or tubercle spots present laterally on body of adults, visible in both sexes;

pharyngeal teeth in one or two rows, numbering almost always 1,4—4,1 or 1,4—4,0,

and 4-4 2

2. Pharyngeal teeth in one row, 4-4 (only one specimen known with 0,4-4,1); lateral body

scales when tuberculate almost always with one tubercle per scale (97 percent), rarely with

two tubercles per scale and never three or more; body tubercles large, about the size of the

average head tubercles, or larger; tubercles commonly on one or two rows of scales below

lateral line. In life, red postocular spot weakly developed, and only noticeable in large

males; pectoral and pelvic fins reddish orange; caudal fin reddish. Southwestern Ohio

River basin in the Green and Cumberland drainages and Duck system of Tennessee

drainage Redtail chub, Nocomis effusus Lachner and Jenkins

Pharyngeal teeth in two rows, 1,4-4,1, rarely 1,4-4,0 (only one specimen with 1,4—4,2);

lateral body scales, when tuberculate, frequently with two tubercles per scale (about

23 percent), sometimes three tubercles per scale (maximum of four observed); body

tubercles small, much smaller than head tubercles; tubercles seldom occurring on second

scale row below lateral line. In life, red postocular spot well developed, observed in both

sexes at sizes as small as 100 mm SL; pectoral and pelvic fins pinkish yellow; caudal fin

pinkish olive. Red and Arkansas drainages Redspot chub, Nocomis asper, new species

Nocomis asper, new species

Redspot chub

FIGURES 1, 2

Hybopsis biguttatus.—Branson 1962:535, fig. 9; 1967:133.—

Hall 1952:57.—Linder 1955:175 [Red drainage].—Reno

1969:739 [in part, Arkansas drainage].

Hybopsis (Nocomis) biguttata.—Davis and Miller 1967:5

[in part].

Hybopsis kentuckiensis.—Meek 1891:126; 1894:85 [Neosho

system].—Evermann and Kendall 1895:471 [in part].

Nocomis biguttatus.—Hubbs and Ortenburger 1929:65 [Arkansas drainage].

Nocomis sp.—Lachner and Jenkins 1967:577 [evolution].

SPECIMENS STUDIED.—HOLOTYPE: USN M 204851:

Arkansas drainage, Oklahoma, Mayes County, Big

Spring Creek at Camp Gailand, 5 mi S. Locust Grove,

7 May 1949, G. A. Moore and class, male, 178.5 mm.

PARATYPES: ARKANSAS DRAINAGE. USNM 204852:

Same data as for holotype. (15 specimens) 30 to 90

mm SL.

OSUMZ 5159: Oklahoma, Cherokee County, Barren Fork River, Muskogee, Boy Scout Camp, (3)

131-165.

OSUMZ 5722: Oklahoma, Cherokee County, Barren Fork Creek, tributary to Illinois River at Camp

Egan. 2 May 1959, G. A. Moore, M. R. Curd, (2)

136-145.

OSUMZ 5106: Oklahoma, Delaware County, Spavinaw Creek, 5.2 mi N. Colcord. 25 June 1955, Linder,

Branson, Greer, and Sutton, (4) 41-143.

TU 48547: Arkansas, Benton County, Spavinaw

Creek, (Hole #3) . 10 June 1966, graduate students,

University of Arkansas, (9) 49-175.

TU 48613: Arkansas, Benton County, Spavinaw

Creek, (Hole #2) . 10 June 1966, graduate students,

University of Arkansas, (28) 39-182.

TU 48658: Arkansas, Benton County, Spavinaw

Creek (Hole #4) . 10 June 1967, graduate students,

University of Arkansas, (14) 43-177.

USNM 193358: Arkansas, Washington County,

Clear Creek, tributary to upper Illinois River. 5 June

1962, K. Strawn and others, (9) 72-176.

OTHER COLLECTIONS (listed by states) : ARKANSAS

DRAINAGE. Arkansas: TU 48645 (7), 59138 (2),

UMMZ 80913 (2), 97774 (3), 103176 (3), 108906-7

(2), 122948 (1), 123465 (1), 123712 (1), 128351 (4),

170912 (1), 175440 (2), USNM 163278 (5).
SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

FIGURE 1.—Lateral view of Nozomis asper, holotype, USNM 204851, a nuptial male, 179 mm

SL, taken 7 May 1949 from Big Spring Creek, Arkansas River drainage. Drawn by C. B.

Gast. (Light postocular spot omitted in Figure 2.)

Missouri: UMM Z 103208 (19), 119995 (1),

151498 (1), 151569 (1), USN M 42855 (1), 63229

(1).

Oklahoma: OSUM Z 103 (2), 132 (1), 428 (2),

528 (1), 2388 (1), 2409 (6), 2410 (2), 2412 (6),

2418 (1), 4828 (1), T U 16585 (5), UMM Z 80915

(2), 116770 (7), 116796 (16), UOM Z 7584 (4),

FIGURE 2.—Dorsal and lateral view of the head of Nocomis

asper, holotype. Drawn by A. M. Awl.

15473 (2), 29504 (1), 29665 (1), USNM 62055 (7),

204854 (8).

RED DRAINAGE. Oklahoma: Johnston County, Blue

River. CU 52267 (12), near Connerville, July 1966.

CU 52401 (15), Connerville, 4 June 1967. NCSM

4733 (3), 1 mi E. Connerville, May 1967. OSUMZ

1499 (2), 10 mi W. Wapanuka, 3 mi S. Route 7 at

Hughes Crossing, 6 April 1947. OSUMZ 2091 (1),

at bridge on Route 99, 5 April 1947. UOMZ 30442

(2), Connerville, 29 July 1960. UOMZ 31134 (16),

Connerville, Route 99 bridge, 1 July 1959.

DIAGNOSIS.—A species of the biguttatus group, most

closely related to Nocomis effusus, but differing from

it in having two rows of pharyngeal teeth, tuberculate

lateral body scales often having two or three tubercles,

pinkish-yellow pectoral and pelvic fins, and a welldeveloped red postocular spot present in both sexes

of subadults and adults.

DESCRIPTION: MORPHOMETRY.—The body proportions of Nocomis asper, general shape and contour, are

close to those described for N. effusus (Lachner and

Jenkins 1967:563). Proportional measurements for five

large males (including the holotype) and five large

females are given in Table 1. In N. asper, as is true for

all species of Nocomis, characters involving allometric

growth have values for males exceeding those of females (except orbit), because the males attain an average larger size than the females. The relative increase

of two characters—head length and snout length—

with increase in body length for N. asper is shown in

Figures 3 and 4.
NUMBER 91

TABL E 1.—Proportional measurements of 5 adult male (including the holotype) and 5 female

Nocomis asper from the Arkansas River drainage {expressed in thousandths of the standard

length)

Character Holotype

SL in mm 178. 5

Head length 292

Snout length 135

Postorbital length 126

Upper lip, length 109

Gape width 114

Orbit, bony length 47

Interorbit, bony width 92

Predorsal length 551

Caudal peduncle length 216

Caudal peduncle depth 107

Body, greatest depth 244

Body, greatest width 164

Pectoral fin length 184

Pelvic fin length 151

X

(174)

(287)

(130)

(121)

(115)

(108)

(46)

(95)

(536)

(221)

(108)

(235)

(160)

(178)

(158)

Range

161-181

274-293

120-135

119-126

105-128

105-114

43-48

89-101

520-551

211-230

104-111

227-244

151-168

168-184

151-167

X

(150)

(278)

(115)

(121)

(99)

(92)

(49)

(79)

(551)

(208)

(99)

(252)

(172)

(163)

(139)

Range

139-166

268-287

112-119

111-128

93-113

89-94

46-53

74-84

540-572

196-215

92-107

244-262

155-182

158-168

132-146

30.5

30.0

29.5

2S.0

<b 28.5

^ 28.0

<3 27 5

•^ 27.0

•S* 26.5

"^ 26.0

^ 25.5

25

-V

• «p

o •

•••• •

o

(3D o

• •

° * °

r, OO

• • _ O • ^ • -

•o,

o

o

•. °

o

o

o

o o

o

o o

J I I I I I I I I I

• = Arkansas 8 Red

o = White

I I I

30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200 210 220

Standard length in mm.

FIGURE 3.—Comparison of head length as percent of standard length, plotted against standard

length in Nocomis asper from the Arkansas River and Red River drainages and N. biguttatus

from the White River drainage. The head lengths were statistically different in these two

populations.
SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

lengt Snout

14.0

13.5

13.0

12.5

12.0

11.5

11.0

10.5

10.0

9.5

9.0

8.5

8.0

7.5

V

o

I I I I I I I

30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180

Standard length in mm.

FIGURE 4.—Comparison of snout length as percent of standard length, plotted against standard

length in Nocomis asper from the Arkansas and Red River drainages and N. biguttatus from the

Great Lakes, Mississippi River and lower Ohio River drainages.

MERISTIC CHARACTERS.—Nocomis asper is a comparatively coarse-scaled member of the species group,

the circumferential scales average about 34 (Table 2),

caudal peduncle scales about 18, and the lateral line

scales about 41.

Vertebrae, counting the hypural plate as one and

the vertebrae included in the Weberian apparatus as

four, average 40.1 (Table 2) from the Red and

Arkansas drainages and range from 39 to 41.

TUBERCULATION.—The discussion of tubercles concerns the nuptial males, on which the tubercles become

enlarged. The tubercle numbers and distribution are

similar in individuals of similar sizes of both sexes,

except that the tubercles in the females appear as light

spots, not readily discernible.

The head tubercles are distributed from about the

midportion of the snout to the occiput (Figures 1 and

2). There is no hiatus in the tubercle distribution on

the snout. A row of several tubercles occurs just below

the nares in the larger nuptial males. The head tubercles of Nocomis asper compare closely with those of

N. biguttatus and N. effusus in number, size, and distribution (Tables 3, 4, and 5). The tubercles are larger

posteriorly on the head and smaller on the forehead
NUMBER 91

TABL E 2.—The number of scales and vertebrae in species of the Nocomis biguttatus group (Great Lakes sample includes

Ohio and upper Mississippi specimens)

Species and locality

biggutatus

Great Lakes, etc

Missouri

Lower Mississippi

White

asper

Arkansas

Red

effusus

All drainages

biguttatus

Great Lakes, etc

Missouri

Lower Mississippi

White

asper

Arkansas

Red

effusus

All drainages

Lateral line

38 39 40 41 42 43 44 45 46 N X

9 29 21 6 4 1 70 39.6

1 4 7 4 3 4 1 1 25 42.0

1 3 5 1 1 11 41.8

8 3 6 14 10 2 43 42.5

5 15 28 25 9 4 86 41.3

1 1 10 9 1 3 2 1 28 41.0

2 18 37 57 20 3 137 41.6

Caudal peduncle

16 17 18 19 20 21 N X

51 15 4 3 1 74 16.5

2 4 8 3 5 22 18.2

2 2 4 3 11 17.7

1 8 15 17 41 19.2

4 22 23 16 21 86 18.3

3 9 11 6 29 17.7

4 9 22 111 1 147 19.7

Circumferential

30 31 32 33 34 35 36 37 38 39 N X

1 5 11 23 20 12 1 73 33.3

2 1 5 5 6 4 2 1 26 35.8

1 1 4 5 2 13 35.5

1 13 16 9 2 41 35.0

2 8 22 27 17 10 2 88 34.0

2 5 12 7 2 28 34. 1

9 42 39 40 13 2 145 36. 1

Vertebrae

38 39 40 41 42 N X

1 42 83 4 130 39.7

1 7 5 13 40.3

2 2 4 39.5

1 32 10 43 40.2

1 12 3 16 40. 1

2 10 3 15 40. 1

10 47 1 58 40.8

and snout. The tubercles are mainly antrorse posteriorly on the head; those on the snout may be antrorse

or erect. A few tubercles near the side of the head are

directed laterally.

The tubercles on the nape and body are located

centrally or subcentrally on the exposed portion of

the scales. The body tubercles are considerably smaller

than those on the head. The tuberculation of the nape

is variable. In some specimens the nape is profusely

tuberculate from the head to the origin of the dorsal

fin, some specimens have the nape only moderately

tuberculate, and in others there are only a few nape

tubercles anteriorly, just posterior to the head. Usually

more tubercles are on the nape near the occiput.

The first and second scale rows above the lateral line

bear the greatest number of tubercles on the body,

laterally; well over one half of the scales are tuberculate. Tubercles occur on scales of the third row

above the lateral line and on the lateral line row, but

the frequency of occurrence is about one half that of

rows one and two above the lateral line. Some tubercles are on the first scale row below the lateral line,

but the number varies from none to twenty nine tuberculate scales in seventeen nuptial males. In some specimens a few scales with tubercles are present on the

fourth row above the lateral line and to a lesser extent

on the second row below the lateral line. The tuberclebearing scales are mainly on the anterior half of the

body. Scales at the end of the caudal peduncle are

free of tubercles.

Tubercle-bearing scales often have more than one

tubercle; in our sample of seventeen nuptial males,

74.9 percent of tuberculate scales had one tubercle, 22.8 percent had two tubercles, and 2.3 percent
SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

TABL E 3.—The number of cephalic tubercles in Nocomis asper from the Arkansas and Red River drainages

{data for the sexes were combined)

SL in mm

50-59

60-69

70-79

80-89

90-99

100-109

110-119

120-129

130-139

140-149

150-159

160-169

170-179

180-189

0 1-

9

4 4

2

10-

19

2

3

1

1

1

2 0 -

29

3

4

—

—

30-

39

—

4

3

—

4 0 -

49

1

1

3

2

2

5 0 -

59

1

1

—

2

Number of cephalic tubercles

6 0-

69

1

2

3

1

1

7 0 -

79

—

3

3

2

—

8 0-

89

2

1

1

2

2

1

90-

99

3

4

3

—

3

100- 110- 120- 130- 140-

109 119 129 139 149

2

2

2 — 1

2 1

3 1

1

Total

number

10

9

11

8

4

2

6

6

10

9

8

5

9

1

had three tubercles per scale (Tables 6, 7, 8, and 9).

The larger nuptial males averaged more tuberculated

scales than the smaller specimens, when the sample of

seventeen males was divided into five 10-mm-size

groups (Table 7).

The head tubercles develop before the body tubercles, appearing first within the area between the posterior internasal line and the midinterorbital line in

juvenile specimens about 50-79 mm SL. There is a

progressive tubercle development posteriorly on the

head with increase in body size. The full head tubercle

pattern is attained in juvenile sizes. As in Nocomis

biguttatus and N. effusus, the tubercles on the snout

and on the subnasal area are the last of the head

tubercles to develop. After the complete pattern of

tubercles on the head appears, there is a progressive

increase in tubercle numbers with increase in body

length (Table 3) through maturity and, apparently,

through successive reproductive seasons. Some males

and females in the group 50-59-mm-size SL had

tubercle spots appearing on the head. The largest

nuptial male examined, 182 mm SL, had about 145

head tubercles.

Almost all specimens under 100 mm SL had no

body tubercle spots, although head tuberculation was

well developed. A few males in the size group 90 to

99 mm SL had a few body tubercles. Gravid females,

120 to 129 mm SL, showed development of some body

tubercle spots. Well-developed tubercles are present

on the dorsal portion of pectoral fin rays 2 to 5 or 6

and sometimes on ray 7.

NUPTIAL CREST OR SWELLING.—No specimen of

Nocomis asper shows evidence of the small swellings

observed in some specimens of N. effusus (Lachner

and Jenkins 1967:562). In all nuptial males of N.

asper and N. biguttatus, as well as almost all N.

effusus observed, the head is free of any development

of a crest; the typical nuptial crests are restricted to

the species of the N. micropogon and N. leptocephalus

species groups (Lachner and Jenkins 1971).

PHARYNGEAL TEETH.—The pharnygeal tooth count

is 1,4-4,1 in 22 pairs of arches from the Arkansas and

Red drainages, 0,4-4-, 1 in one specimen and 1,4-4,2

in one. The tooth count is similar to that of Nocomis

biguttatus. In a sample of 52 N. biguttatus from the

Great Lakes, Ohio, Mississippi, and Missouri drainages 47 pairs of arches had a pharyngeal tooth count

of 1,4-4,1, five had 1,4-4,0 or 0,4-4,1, and one specimen was questionably 4-4. In size and shape the arch

is similar to that described for N. effusus. (Lachner

and Jenkins 1967:564). The stout teeth and arches

of the three members of the biguttatus group are

probably indistinguishable.

COLORATION.—The following observations were

taken from the holotype by George A. Moore on 7 May

1949 at the time of capture: a red postocular spot;

pectorals and pelvics pink on outer two thirds, yellow

on inner one third, the fin rays darkened with melanin
NUMBER 91

TABLE 4.—The number of cephalic tubercles in Nocomis biguttatus from the White River drainage

(data for the sexes were combined)

SL in mm

50-59

60-69

70-79

80-89

90-99

100-109

110-119

120-129

130-139

140-149

150-159

160-169

170-179

180-189

190-199

200-209

210-219

1-9 10- 20- 30- 40-

19 29 39 49

1

1

1 2

1 2 1

1 — 2

50- 60-

59 69

1

1

1

2

Number of cephalic tubercles

70-

79

1

2

1

1

1

1

8 0 -

89

—

5

1

—

2

1

1

1

90-

99

1

3

—

1

—

—

—

1

100-

109

1

1

1

2

—

1

—

110- 120- 130- 140- 150-

119 129 139 149 159

o

I l

— 2 1

— — — 1

o i

1

Total

number

1

1

3

4

4

1

3

7

1

7

2

6

6

5

3

4

1

on the distal one fourth; anal fin pale; belly slightly

washed with pink; caudal fin with some pink; dorsal

fin rays outlined in black, the interradial membranes

clear.

Other life colors of nuptial males and females observed over the nests and spawning were recorded by

the authors on 7 and 12 June 1967, in Spavinaw and

Flint Creeks, Delaware County, Oklahoma. The nuptial males have a faint dark midlateral band on body.

The body is olivaceous, laterally. The belly, chin, and

branchiostegals are light rosy to pinkish. The postocular

spot is red or reddish orange, prominent, sharply outlined, almost circular, and seen on subadults and

adults, and also on mature females at 100 mm SL;

some smaller juveniles have a pale, brassy postocular

spot. The tuberculated area of the head is smoky blue;

the tubercles are whitish. The pectoral fin is olive to

pinkish on the outer half, and light orange to pinkish

yellow basally. The dorsal fin is olive, the rays dark.

The pelvics and anal fins are somewhat dark basally,

the first ray milky orange, and the distal half light

pinkish orange. The lobes of the caudal fin are light

pinkish orange, the color becoming light olive basally

on the fin. The caudal fin is noticeably pale in life compared with the brilliant orange-red caudal fin of

Nocomis effusus. The middorsal light stripe was faint

in adults of both sexes.

The large females are colored pale olive to greenish

olive dorsolaterally. The outer portion of the caudal

fin is very light orange, the basal portion pale. The

other fins are pale with a light orange tinge.

In preservation, the nuptial males lack the dark

lateral band on the body as well as the basicaudal spot,

or they are very faint. Some of the adult females and

larger juveniles of both sexes have a moderately developed dark, lateral body band and a conspicuous round

basicaudal spot. The color pattern of Nocomis asper

in preservation in respect to size and sex of specimens

is similar to the pattern of N. biguttatus (Lachner

1952; Lachner and Jenkins 1967).

ETYMOLOGY.—The specific name, asper, refers to

the rough head and body of the nuptial male caused

by the development of many tubercles; the common

name, redspot chub, is in reference to the bright red,

postocular spot present on the adults and subadults

of both sexes.

REPRODUCTION AND GROWTH.—Nocomis asper, as

in all other species of Nocomis, is a nest builder. Nest

construction, spawning, reproductive and other behavior were observed by the authors on 7 and 12 June,

1967. These studies will appear in a separate paper on

reproductive behavior in the genus Nocomis.

The largest male examined was 182 mm SL. Seventeen nuptial males ranging from 143 to 182 mm in
10 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

TABLE 5.—The number of cephalic tubercles in Nocomis biguttatus from the Missouri, Mississippi, Ohio, and Great

Lakes drainages (data for the sexes were combined)

SL in mm

40-49

50-59

60-69

70-79

80-89

90-99

100-109

110-119

120-129

130-139

140-149

150-159

160-169

0 1-

9

1

1 4

10-

19

3

1

20-

29

—

4

7

12

4

3 0-

39

1

2

12

31

21

7

Number of cephalic tubercles

4 0-

49

1

8

40

51

17

6

4

1

5 0-

59

2

15

28

25

13

9

2

6 0-

69

4

6

8

10

11

1

1

7 0-

79

1

—

6

7

4

8

2

80- 90- 100- 110-

89 99 109 119

1

2

2 1 — 1

2 — 1

3 1

1

Total

number

1

9

7

30

103

111

65

47

31

16

3

—

1

length averaged 167.2 mm. The largest female asper

examined was 168 mm SL. Also, as in other species of

Nocomis, the males of N. asper attain the larger size.

Some females are mature, having enlarged ovaries, at

100 to 110 mm SL.

Nocomis biguttatus (Kirtland)

Hornyhead chub

FIGURES 5, 6, and 7

Semotilus biguttatus Kirtland, 1840:344, pi. 5, fig. 1 [type

locality: Yellow Creek, Mahoning River, Ohio River

system, Ohio].

Ceratichthys cyclotis Cope, 1864:277 [lectotype, ANSP 2113;

type locality: Michigan, herein designated].

Ceratichthys stigmaticus Cope, 1864:278 [type locality:

Michigan].

Hybopsis kentuckiensis. — Fowler 1918:33, plate VIII

[redescription].

Nocomis biguUatus.—Hubbs 1926:28, pi. I, fig. 1; pi. II,

fig. 3.

Nocomis nebrascensis Girard, 1856:190 [type locality: Sweet

Water River, Platte River system].

NOMENCLATURE.—Certain nomenclatural problems

involving Nocomis biguttatus commenced when

Rafiinesque (1820:48) described Luxilus kentuckiensis,

which was a composite account, probably involving

species of Nocomis and perhaps species of Notropis.

This early history is briefly reviewed by Lachner and

Jenkins (1967:558-559). The next available name

for a species of Nocomis was Kirtland's description of

Semotilus biguttatus (1840:344). His specimens were

taken in Yellow Creek, a tributary of the Mahoning

River, Ohio. His description and illustration of the

nuptial male (Plate 5, Figure 1) and coloration easily

identify the above synonyms with the species of Nocomis that Kirtland had found. One problem remains

which could involve the security of the entrenched

name Nocomis micropogon (Cope). Cope (1864) described two species of Nocomis on page 277,

Ceratichthys cyclotis and Ceratichthys micropogon (as

well as another one, Ceratichthys stigmaticus on page

278). Lachner and Jenkins (1971) discuss the hybrid

nature of Cope's type specimen (ANSP 5061) of

Ceratichthys micropogon and conclude that it probably

represents a hybrid Nocomis micropogon X Notropis

cornutus, based on a number of morphological characters. Lachner and Jenkins (1970) restricted the name

Ceratichthys micropogon Cope to that presumed parent of the type specimen. But Cope's description of

Ceratichthys cyclotis involves both Nocomis biguttatus

and N. micropogon. The type material came from

Michigan, at Grosse Isle, and from Waterford, Oakland County, from Clinton River, and from Bruce,

Macomb County. Hubbs (1926:29) indicated that

Cope's description may have been based on the above

two species. Cope recorded the dentition as variable,
NUMBER 9 1 11

FIGURE 5.—Lateral view of Nocomis biguttatus, USNM 166459, a nuptial male, 99 mm SL,

taken 21 July 1939 from Johnson Creek, Lake Ontario drainage, New York. Drawn by C. B.

Gast.

"in some specimens of this species, especially among

the half-grown, I find a tooth of the second row of

pharyngeals." Hubbs further commented that Fowler's

(1918:33) redescription of the species amounts to a

restriction of the name biguttatus. Fowler, however,

records the dentition as that of micropogon, \-A.

Examination of the extant types of Ceratichthys

cyclotis (ANSP 2113-2117, 5 specimens) reveals two

species. We designate ANSP 2113, a nuptial male, 132

mm SL, a lectotype of Ceratichthys cyclotis Cope, 1864,

and place it in the synonymy of Nocomis biguttatus

Kirtland, 1840, because of its dentition, 1,4-4,1, and

FIGURE 6.—Lateral view of head of Nocomis biguttatus, USNM 193359, a nuptial male, 194 mm

SL, collected 7 June 1962 from Brush Creek, White River drainage, Washington County,

Arkansas. (The only specimen having an atypical tubercle just below nape on one side. See

Lachner and Wiley, 1971, for presence of supernumerary nape tubercles in N. leptocephalus).
FIGURE 7.—Dorsal and lateral views of the head of a nuptial

male Nocomis biguttatus, USNM 166459, 99 mm SL. Same

specimen as Figure 5. Drawn by C. B. Gast.

the widespread occurrence of tubercle scars, dorsally,

on the head, extending from the posterior area of the

snout to the occiput. The following numbers are designated paralectotypes: ANSP 2114, 101 mm SL and

ANSP 2115, 60 mm SL. Both specimens have two

rows of pharyngeal teeth, and indications of a once

large dark spot at the base of the caudal fin, or postorbital head tubercles. ANSP 2116, 62 mm SL, may

have had two rows of pharyngeal teeth, but the arches

are in poor condition; since the specimen is otherwise

SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

faded and shows no tubercle marks, it may represent

either N. biguttatus or N. micropogon. (We suspect

that it is N. biguttatus.) ANSP 2117, 142 mm SL, is

referred to N. micropogon because it has a dentition

of 4—4, and the tubercle spots are located in the internasal and subnasal areas. With the above lectotype

restriction of Ceratichthys cyclotis Cope, 1864, the

name is not available for Ceratichthys micropogon

Cope, 1864.

SPECIMENS STUDIES.—Nocomis biguttatus has an

extensive distribution primarily in the central basin of

the United States (Figure 8). It is the key species in

understanding the evolution, ecology, and distribution

of the species group. The specimens listed below represent material from which morphological data were

recorded. An attempt was made to study the larger

specimens available in museum collections from samples widely scattered within the various river systems

of the area.

MISSISSIPPI BASIN

WHITE DRAINAGE.—Arkansas: KU 3242 (1),

OSUMZ 5994 (2), TU 10130 (5), 44685 (2), 44710

(2), 44817 (1), 46953 (3), 49386 (2), 49473 (1),

49804 (1), UF 14704 (3), UMMZ 123903 (1),

128305 (1), 169890 (1), 170895 (1), USNM 42684

(3),42677(1), 193359 (10).

Missouri: KU 11014 (2), UMMZ 102586 (1),

102712 (2), 111459 (1), 151091 (7), 151320 (1),

151367 (1), 152061 (2), USNM 42814 (1), 42882

(1),204018 (10),204855 (34).

ST. FRANCIS DRAINAGE.—Missouri: UMMZ 139507

(I)-

MERAMEC DRAINAGE.—Missouri: CU 10783 (4),

UMMZ 148338 (1), 148389 (2), 148441 (1), 149630

(2), 149664 (1), 149816 (2).

MISSOURI BASIN

GASCONADE DRAINAGE.—Missouri: CU 24323 (3),

UMMZ 102721 (1), 111436 (2).

OSAGE DRAINAGE.—Missouri: UMMZ 86532 (1),

102748 (3), 102804 (1), 111355 (1), 150102 (4),

150092 (2), 150377 (1), 150465 (1), 150881 (1),

150917 (2), 150942 (1), 151944 (1), 152694 (1).

Kansas: KU 2470 (2), 2498 (10), 2605 (7),

UMMZ 61214 (1), 126847 (1), 160538 (1).

MISSOURI DRAINAGE.—North tributaries: UMMZ

147948 (1), USNM 35876 (1).

KANSAS DRAINAGE.—Kansas: KU 426 (1), 427 (1),

429 (1), 438 (1), USNM 3551 (1).
NUMBER 91 13

MISSOURI DRAINAGE.—Nebraska: USN M 86694

(1).

Iowa: UMM Z 114088 (3).

UPPE R MISSISSIPP I BASIN

Missouri: UMM Z 148252 (1).

Illinois: UMM Z 144502 (1), USN M 171692 (2).

Indiana : UMM Z 81365 (4), USN M 66457 (3).

Iowa: T U 14498 (6), UMM Z 87066 (1), 87075

(1), 101200 (1), 101214 (1), 101234 (1), 101244 (1),

101270 (1), 101288 (1), 101308 (2), 101366 (1),

101376 (1), 101387 (2), 101399 (1), 146829 (2),

146849 (2).

Wisconsin: UMM Z 74187 (2) 74362 (1), 75579

(3), 75618 (1), 75648 (2), 75808 (1), 75925 (1),

76699 (2), 76854 (2), 76922 (2), 77031 (1), 77056

(1), 77184 (1), 77238 (1), 77483 (2), 77558 (2),

77574 (1), 77933 (6), 78956 (1), 96137 (4), 96148

(1), 96181 (4), 96227 (2).

Minnesota: USN M 133094 (4).

South Dakota: UMM Z 166896 (6), 167000 (6),

167131 (1).

OHI O BASIN

Kentucky: C U 37297 (5), U L 10479 (1), 12465

(1), 12620 (6).

Indiana : UMM Z 6662 (1), UMM Z (I U 9549)

(1), 99904 (8), 99952 (2), 112746 (1), 112747 (1),

USN M 66449 (1), 69245 (2).

Ohio : UMM Z 86964 (1), 87203 (2), 107667 (1),

118369 (1).

Pennsylvania: C U 33875 (4), 40731 (1), 46677 (2),

USN M 166418 (5), 166419 (2), 166420 (7).

GREAT LAKE S BASIN

New York: C U 659 (3), USN M 166437 (2),

166452 (3), 166456 (6), 166457 (7), 166459 (2),

166460 (6), 166463 (2), 166464 (6), 166465 (7),

166468 (8), 166469 (4), 166475 (19), 166478 (2).

Ontario: UMM Z 85516 (1), 89023 (3), 89078 (1).

Ohio: UMM Z 121801 (2), 121810 (5), 121832 (3),

121853 (2), USN M 40096 (3).

Indiana : UMM Z 114919 (1).

Michigan: UMM Z 55272 (1), 60230 (2), 61387

(1), 68285 (1), 69039 (1), 69060 (1), 69085 (3),

69123 (1), 69129 (3), 69143 (5), 70558 (1), 79096

(1), 79881 (1), 80731 (1), 81500 (2), 82609 (2),

82975 (1), 83087 (1), 83146 (2), 83231 (1), 83267

(1), 83411 (1), 83543 (1), 83771 (1), 83913 (1),

84650 (2), 84681 (2), 84758 (2), 84802 (3), 84951

(1), 86292 (2), 89454 (2), 89595 (2), 92108 (1),

96987 (1), 97242 (2),98410 (2), 101908 (1), 101958

(1), 104120 (1), 106876 (2), 106902 (1), 110352 (1),

113321 (1), 116249 (1), 116335 (1), 116972 (1),

117014 (4), 117137 (1), 131946 (1), 136822 (1),

136944 (1), 137148 (1), 137217 (1), 137287 (1),

137649 (1), 137672 (1), 137692 (16), 137701 (1),

137731 (3), 138070 (5), 139797 (1), 139804 (2),

139834 (2), 140215 (1), 162738 (8), 164288 (19),

164376 (12), 167826 (5), 185397 (3), 185398 (2),

185400 (3), 185406 (3), 185411 (2), 185414 (5).

Wisconsin: UMM Z 64516 (3), 64522 (2), 64663

(3), 64902 (2), 72884 (1), 72975 (4), 73892 (4),

73963 (2), 74087 (1), 74159 (1), 74285 (1), 74894

(5), 74940 (5), 76713 (1), 76763 (1), 77794 (3),

78532 (1), 87029 (2),97150 (1), 108084 (1), USN M

143015 (3),WSU46 6 (7).

T h e plots on the map for the distribution of Nocomis

biguttatus (Figure 8) are based on two sets of data.

One set includes the specimens listed above, and hundreds of additional collections examined in these

museums, which, while of no immediate systematic

value, were important in the locality data they provided and contributed to a better understanding of the

distribution, ecology, and zoogeography of the group.

Because of the thousands of specimens involved, it is

prohibitive to list all of these collections herein.

Another set of distributional data were taken mainly

from comprehensive state faunal surveys. These records, often extremely abundant, were used to round

out aspects of the distribution of a local nature, from

which we saw no material. Th e references from which

these data were taken, listed by author with the state

or province involved, are as follows: Cross (1967,

Kansas), Ellis (1914, Colorado), Bailey and Allum

(1962, South Dakota), Keleher (1956, Manitoba),

Hinks (1943, Manitoba and North Dakota), Cleary

(1956, Iowa), Forbes and Richardson (1920, Illinois;

N. micropogon apparently is confined to the Wabash

system in Illinois), Gerking (1945, Indiana), Greene

(1935, Wisconsin), Taylor (1954, Michigan), Trautma n (1957, Ohio), Raney (1938, Pennsylvania),

Underhill (1957, Minnesota), Simon (1946, Wyoming), and Copes and Tub b (1966, North Dakota).

Locality records for collections in the Royal Ontario

Museum, Toronto, Canada, were taken from a list

provided by W. B. Scott. Distributional records for

New York were checked against the data published in

the New York State Biological Survey Reports.
14

SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY
NUMBER 91 15

DIAGNOSIS.—Nocomis biguttatus is a wide-ranging

species, most closely related to N. asper in having two

rows of pharyngeal teeth. It differs from N. asper and

N. effusus in never having tubercles on the scales of the

body, laterally. It is a coarser scaled species than N.

effusus. The red postocular spot is intermediate in its

development in N. biguttatus, compared with its two

species-group relatives. In N. biguttatus the red spot is

well developed only in adult males, and is brassy

colored or not evident in adult females. In N. asper the

red spot is conspicuously developed in adults of both

sexes. In iV. effusus the red spot is present, but faint, in

the large males only.

Comparison of Species in the Biguttatus Group

The primary differentiation among the three species

is in the tuberculation of the body, the reduction of

teeth on the pharyngeal arch from two rows to one

row, the development of coarser and finer scaled

species, the elongation of certain body proportions, as

length of snout and head, and the development of

certain nuptial colors in the males.

Counts of the head tuberculation revealed that the

three species have about the same number of head

tubercles and the same increments in tubercle numbers with increase in body length (Tables 3, 4, and

5). Where large samples of nuptial males were available from particular drainages, great variability existed in the number of head tubercles within any

of the groups classified by a range of 10 mm in body

length. The group of Nocomis biguttatus 70 to 79 mm

in size has specimens in which the number of head

tubercles exceed others by three times or more. The

same variation existed in the larger specimens. All three

species had a high variability in the number of head

tubercles within any given size-group. Preliminary

counts suggested differences in the number of head

tubercles among the three species and among drainage

populations of N. biguttatus, but as more adult specimens became available these differences proved unreal, for they were associated primarily with body size.

FIGURE 8.—Distribution of the three species of the Nocomis

biguttatus species group. Locality data for N. asper are listed

in "Materials Studied." The basis of the plots used for N.

biguttatus is explained in the text. The shaded area marks

the aproximate range of N. effusus, which was taken from

Lachner and Jenkins (1967, figure 7).

N. biguttatus is apparently a small species over most

of its range, excluding those of the White River drainage, and it is much smaller than N. effusus or N. asper.

Only one specimen was examined which exceeded 150

mm SL (Table 5)—a gravid female, 162 mm from

Weber Lake, Lake Michigan drainage. Many males

of N. biguttatus in the Great Lakes drainage are

mature, and with head tubercles enlarged, at 100

mm, and the females are gravid at 90 mm. Apparently,

N. biguttatus in the White River drainage attains the

largest size among the drainage populations and among

the members of the species group.

In one collection, USNM 204018, eleven specimens

from the North Fork of the White River, Ozark

County, Missouri, five males exceeded 200 mm SL

(compare data in Tables 3, 4, and 5, and Lachner

and Jenkins 1967, Table 1). One of these specimens

also had about 155 head tubercles, the highest number

found among the three species.

Nocomis effusus may be a larger species than N.

asper; five nuptial males of the former attained body

lengths of 161 to 202 mm and averaged 179 mm.

Seventeen nuptial males of the latter species ranged

from 143 to 182 mm and averaged 167 mm.

Although tuberculation on the body, laterally and

on the nape, increases with increase in body length,

there are two notable differences in the development

of body tubercles among the three species. First,

Nocomis biguttatus does not develop body or nape

tubercles, excluding one or two supernumerary occipital tubercles that may be present in the largest

nuptial males. The body tubercles only appear on N.

asper and N. effusus. They also are absent on all numbers of the micropogon group and leptocephalus group.

Secondly, the body tubercles on N. asper have differentiated significantly from those on N. effusus in the

number of tubercles per scale. The total number of

tubercles on the tuberculated lateral body scales was

about the same in both species (Table 6, N. asper,

seventeen specimens range from 28-112 total tubercles,

average 82.2; N. effusus, five specimens range from 25-

116 total tubercles, average 86.6). Only 3 percent of

the tuberculated scales in N. effusus had two tubercles

per scale, and no scales had more than two tubercles.

About 23 percent of the tuberculated scales in N.

asper had two tubercles (Tables 8 and 9), 2 percent

had three tubercles, and one specimen had one scale

with four tubercles. There is a great range in N. asper

in the number of tuberculated scales having either
16

one or two tubercles per scale. Nuptial males may

have only 26 scales bearing one tubercle and other

larger specimens have 82 to 86. Some specimens have

less than 10 scales bearing two tubercles and other

specimens may have 30 to 50 scales bearing two

tubercles (Tables 8, 9). The smaller nuptial males

of both species averaged fewer tuberculated scales

(Table 7). In N. asper, the 10-mm-size groups from

140 to 180 mm SL, had average values for number

of tuberculated scales of 64, 75, 85, 85, and 112.

Tuberculation on the nape was highly variable but

the larger specimens of both species had more tubercles. The nape tuberculation is probably more extensively developed and more tubercles are present in

Nocomis asper than in N. effusus. The body tubercles

in N. effusus are about the size of the average head

tubercles, whereas in N. asper the body tubercles are

much smaller than in N. effusus, about one half the

size of the average head tubercles. The head tubercles

are about equal in size in all three species of the

biguttatus group.

There is nearly a complete separation of Nocomis

asper and N. biguttatus from N. effusus in the pharyngeal dentition. The former two species have two rows

of teeth with the following counts: N. asper, 1,4-4,1

(22 pairs of arches), 0,4-4,1 (1), 1,4-4,2 (1); N.

biguttatus, 1,4-4,1 (47), 1,4-4,0 or 0,4-4,1 (5), and

4-4 (1, questionable). N. effusus has one row with

4-4 (28 pairs of arches) and 0,4-4,1 (1).

A summary of the differences in squamation

among the three species is given in Table 2 involving

three different scale counts, the lateral line, circumferential, and caudal peduncle. The data for Nocomis

biguttatus were grouped by four general areas: (1)

the Great Lakes drainage including the Ohio and

upper Mississippi River drainage, (2) the Missouri

drainage, (3) the lower Mississippi drainage area, and

(4) the White River system. We were particularly

interested in the White system because of its geographic

location between the Arkansas River to the south (and

adjacent headwaters) and the northern and eastern

systems of the Missouri, Mississippi, and Ohio basins.

Although the number of scales is of minor value in the

identification of the species, the character has systematic value in showing trends and relationships among

the species and among populations of N. biguttatus.

N. effusus is finer scaled, which is shown particularly

in the high values of the circumferential count (avSMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

erage 36.1 scales) and the caudal peduncle count (average 19.7). N. asper is somewhat more coarse-scaled

than N. biguttatus of the White drainage. The northern and eastern populations of N. biguttatus, in

the Great Lakes, Ohio, and upper Mississippi

drainages, were consistently lower in all three scale

counts when compared with those from the Missouri,

lower Mississippi, and White drainages (and also with

those counts of N. asper and N. effusus).

The vertebral numbers (Table 2) were higher in

Nocomis effusus (modally 41) compared with those of

N. asper (modally 40) and N. biguttatus (modally 40).

Our first observations of Nocomis asper, based on

a few large males, indicated that it was a long-head,

long-snout form. As more material accumulated, particularly larger specimens, it became possible to test

statistically these preliminary observations. Because of

the contiguous distribution N. asper has with N. biguttatus, its close relationship with this species, and probable evolution from biguttatus stock, more detailed

comparisons of head lengths were made between these

two species. The relationship between standard length

and head length of N. asper and N. biguttatus from

the White River drainage is shown in Figure 3, based

on a sample of measurements of juveniles and adults

distributed as widely over the drainages as the collections permitted.

Statistical tests were performed to compare the relationship between standard length and head length of

Nocomis asper with each of the following populations

of N. biguttatus: The White drainage, the Missouri

drainage, and the Great Lakes drainage including the

Ohio and Upper Mississippi drainages. Tests of differences of slopes and heights (intercepts) of pairs of

regression lines were performed by analysis of covariance (Simpson, Roe. and Lewontin, 1960). F values

yielding probabilities greater than 0.95 were considered significant. The samples tested were randomly

selected from several hundred measurements of specimens from each population; these specimens were

widely distributed within the area tested. The regression equations are as follows:

^ ;

N. biguttatus (White drainage), y=.0063X +26.64,

n=70;

N. biguttatus (Missouri drainage), y=.0141X +

26.48, n=60;

N. biguttatus (Great Lakes), y=.0114X + 26.12,

n=100.
NUMBER 91 17

TABLE 6.—The number of body tubercles per scale in nuptial males of seventeen specimens of

Nocomis asper and five specimens of N. effusus. Under the heading "tubercles per scale"

is given the number of specimens and the mean and range of scales bearing from one to four

tubercles with this data also in percentages (body tubercles counted on left side)

Species, number of

specimens, x, range

asper

17(167.2)

143-182

In percent:

X

Range

effusus

5(179.0)

161-202

In percent:

X

Range

Tubercles per scale

1 2 3 4

17(60.0) 17(11.0) 8(4.3) 1(1)

26-86 2-42 1-15 —

(74.9) (22.8) (2.3) —

45-93 7-47 1-15 —

5(85.6) 3(1.7) —

25-116 1-3 — —

(99.0) (1.0)

97-100 1-3 — —

Total number

of tubercles

17(82.2)

28-112

5(86. 6)

25-116

TABL E 7.—The number of specimens and the mean and range of body tubercles per scale, by size

groups, in nuptial males of N. asper an d N. effusus

SL in mm

asper

140-149

150-159

160-169

170-179

180-189

effusus

160-169

170-179

180-189

190-199

200-209

Tubercles per scale

I 2 3 4

2(36.5) 2(19.5) 1(15)

26-47 2-37 —

3(51.0) 3(22.0) 1(7)

40-72 3-12

3(61.7) 3(23.0)

56-67 13-37

8(67.3) 8(18.6) 6(2.0) 1(1)

45-82 6-30 1-4

1(86) 1(26)

2(56.5) 1(1)

25-88 —

1(92) 1(1)

1(116)

1(107) 1(3)

Total tubercle

number

2(63. 5)

28-99

3(75.3)

44-93

3(84. 7)

75-93

8(84. 9)

55-102

1(112)

2(57. 0)

25-89

1(93)

1(116)

1(110)
18 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

TABL E 8.—The number of tubercles per scale on the body in nuptial males of seventeen specimens

of N. asper and five specimens of N. effusus {expressed in percent of the total number of

scales bearing tubercles)

Species and

number of

tubercles

per scale

asper

1

2

3

4

effusus

1

2

1-9

2

7

1

3

Tubercle numbers per specimen in percent of scales bearing tubercles

10-19 20-29 30-39

3 9 1

1

40-49 50-59 60-69 70-79 80-89

2—36 3

2

90-100

3

5

The slope of the regression of head length (as percent of SL) on standard length of Nocomis asper is

significantly different from N. biguttatus of the White

drainage (F = 8.71; 190 degrees of freedom). The

slope of the regression of head length (as percent of

SL on standard length of N. asper was not statistically

different from that of N. biguttatus of the Great Lakes

drainage (F = .4O; 220 degrees of freedom), but the

heights were significantly different (F=36.38; 221

degrees of freedom). The slope and height for data

of N. asper were not statistically different from those

of N. biguttatus from the Missouri drainage (slope:

F = .O4, 180 degrees of freedom; height: F=<.05 ,

181 degrees of freedom). It is of interest that N. asper

and N. biguttatus of the White drainage, the two adjacent populations, have the greatest difference in head

length.

Many body proportions of the species of Nocomis

show allometric growth (Lachner and Jenkins 1971;

Lachner and Wiley 1971), an increase in body length

resulting in an increase in size of structure. The relationship of snout length to standard length of N. asper

and N. biguttatus from the Great Lakes drainage (Figure 4) shows the same general growth trends and

differences as head length. Considerable variability

occurs in the size of the proportional character within

each population and within the 10-mm-size SL groups.

Such proportional characters, however, are useful in

describing populations and in demonstrating differentiation among populations and species of Nocomis.

The three species show consistent differences in life

in the intensity of development of the red postocular

spot, in the color of the fins, and in the development

of the dark lateral body band. These comparisons pertain mainly to the nuptial males. The red postocular

spot is large, conspicuous, and intensely developed in

Nocomis asper on specimens of subadults to adults

(and present in mature females at sizes of 100 mm SL

or greater). It is well developed only in the larger,

mature males of N. biguttatus and is brassy colored in

some adult females. It is small and weakly developed

in the largest nuptial males of N. effusus, often absent

in the smaller nuptial males, and absent in all other

individuals.

The most intense and noticeable life colors occur in

adult males of Nocomis effusus, in which the fins—particularly the caudal, pelvic, and anal—are bright

orange or reddish orange. The pectoral fin is bright

in N. asper, being predominantly pinkish yellow to

pinkish orange. The pelvic, anal, and caudal fins are

mainly pinkish olive or light pinkish orange. N. biguttatus develops the weakest fin colors among the three

species; the pectoral fins are orange, the pelvics and

anal fins are pale orange, and the caudal fin is light

orange red.

The dark lateral band on the body is prominent in

nuptial males of Nocomis biguttatus, weakly developed

in N. asper, and almost completely absent in N. effusus.

The young to subadult males and most all-size stages

of the females have subdued colorations and they are,

other than the differences discussed above, fairly similar

in their general color pattern. More detailed descriptions of color and color patterns are given by Lachner

(1952) and Lachner and Jenkins (1967).
NUMBER 91 19

TABLE 9.—Total number of body tubercles per scale in nuptial males of seventeen specimens of

N. asper and five specimens of N. effusus

Number of

tubercles per scale

asper

1

2

3

4

effusus

1

2

1-

9

4

7

1

3

10-

19

5

1

Tubercle numbers per specimen, of scales bearing tubercles

20-

29

1

4

1

30-

39

3

_

40-

49

4

1

50-

59

3

60-

69

3

70-

79

4

_

80-

89

2

1

90-

99

1

100-

109

1

110-

119

1

Distribution and Ecology

The distribution of the three species of the biguttatus

group is shown on Figure 8. The extensive distribution

of Nocomis biguttatus in the central basin contrasts

markedly with the restricted distributions of N. asper

and N. effusus. N. asper has a center of distribution

in the Ozark highland section of the Arkansas River

drainage. It is absent in the western tributaries of the

Neosho system. Hall (1952:57) reported it only from

the upland tributaries of the east side of Grand

(Neosho) River. Branson (1967:133) found it "very

abundant in most of the eastern clear tributaries but

is absent from the main (Neosho) stream."

Three isolated populations of Nocomis, two in the

Arkansas drainage which possibly represent N. asper,

and one in the Red drainage, definitely N. asper, are

apparent evidence of what was once a much greater

distribution of the species. In the upper Arkansas drainage of Kansas, Cross (1954) reported Hybopsis biguttatus (-N. asper?) as rare in the South Fork of the

Cottonwood River and that juveniles were common in

Cedar Creek, both of the Neosho River system. These

localities are plotted on the Kansas map by Cross

(1967:87). Cross and Braasch (1969) did not capture

the species in their 1967 survey whereas it was present

in 1952 (1954 report) in one half of all collections

made. We have examined the following Nocomis collections from the Neosho River system in Kansas:

KU 2704 (1), KU 2718 (16), UMMZ 116059 (1),

and UMMZ 120801 (1). All of these specimens were

young and juvenile sizes under 83 mm SL, and we

could not specifically identify them because of their

small size. These specimens are indicated on Figure 8

by a question mark and they may represent either

N. asper or iV. biguttatus. A single, isolated western

record (Figure 8) of Nocomis in north-central Oklahoma, Arkansas River drainage, is tentatively referred

to N. asper. One specimen, UOMZ 15475, 71 mm SL,

was taken near Turkey Island, Panner County, on

8 April 1933 by George A. Moore, where according

to Hubbs and Moore (1940:92) "large springs emerge

in the bed of the main river." A third isolated population occurs in south-central Oklahoma (two plots on

Figure 8) where we have examined seven collections

from the Blue River, Johnston County, Red River

drainage. The Blue River is the only portion of the Red

drainage inhabited by Nocomis. A good series of large

specimens had the typical body tuberculation of

N. asper and otherwise agreed with the characters of

this species. N. asper was taken from the Blue River in

1947 by Linder (1955:175, as Hybopsis biguttata).

R. E. Jenkins and F. F. Snelson, Jr., found N. asper

very common in the Blue River system in 1967.

The disjunct occurrence of these three populations

from the main one in the Ozark upland, Arkansas

drainage, closely parallels isolated populations of Notropis pilsbryi. Cross (1967: 110) shows the distribution of Notropis pilsbryi in the upper Neosho system

where it occurs as a relic, occupying clear, flowing

water with a substrate of rubble and gravel. Notropis

pilsbryi once occurred with Nocomis asper at the isolated western station of the Arkansas drainage near

Turkey Island, Panner County (Hubbs and Moore
20 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

1940: 94, Figure 1; Gilbert 1964: 133, Map 2). It

was reported from the Red drainage at three localities, each in a separate tributary by Hubbs and Moore

(1940: Figure 1). The species was recently captured

from the Blue River, a fourth locality in the Red

drainage. These isolated populations of Nocomis

asper and Notropis pilsbryi appear to be remnants of

a fauna that was formerly much more widely distributed. They do not seem to be products of introductions or accidental transfer of data, as was suggested

by Hubbs and Moore (1940: 94) for Notropis pilsbryi. Other evidence suggests a natural distribution

of these species, such as the close compatibility between them during spawning. Notropis pilsbryi is one

of the common nest associates of Nocomis asper. While

the latter species constructs a gravel mound in the

reproductive process, the former species occupies the

nest as a spawning site, often in large numbers, with

practically no antagonism shown between the two.

Both species prefer clear, flowing streams with clean

gravel, rubble, and sandy substrates.

The wide distribution of Nocomis biguttatus shows

interesting gaps, some of which are related to the immediate erosional history of the central basin, while

others are associated with the geology and glacial history of the area. Climatic factors, such as droughts,

also have affected the general distribution and occurrence of Nocomis biguttatus. The hornyhead chub

is common on the Ozark upland of Arkansas and Missouri with some scattered populations at lower elevations. The species is fairly common in the low elevation areas of the upper Osage drainage. Deacon and

Metcalf (1961) did not collect this species in the

Wakarusa River system draining northeastern Kansas.

They report (page 316) that it was common in early

collections but that it has not been taken since 1924.

Its disappearance is probably related to increased siltation and intermittency of stream flow. Metcalf (1966:

105) found the hornyhead chub to have one of the

most restricted ranges of any fish in the Kansas River

drainage. He lists earlier records and museum specimens, some dating back more than 100 years. Some

of these earlier records appear on the distribution map

of Figure 8. The occurrence of Nocomis biguttatus in

the Missouri River drainage today is limited to a few,

widely separated populations. Metcalf points out that

its extirpation in the Missouri drainage is much like

that described in Ohio by Trautman (1957) where fine

siltation due to cultivation has covered coarser sediments. The water has become more turbid, with reductions in flow and volume, and the streams are now

intermittent in some areas. The ecological conditions,

such as clear, constantly flowing streams with gravelrubble bottoms that once provided suitable habitat

for this gravel-mound, nest-building chub to maintain

a wide distribution, are now largely in a state of attrition. Extirpation of the species through change of

habitat, and increased competition from species more

highly adapted to silt-bearing waters, is now leading

to its confinement in numerous scattered localities.

Our single plot (Figure 8) in northwest Missouri is

an 1884 record of Jordan and Meek (1885:12) from

Hundred and Two River. The plot in eastern Nebraska

is based on a specimen from Papillion River (USNM

86694) received from the Museum of Comparative

Zoology, Harvard, and was taken by the Hassler Expedition prior to 1872. It is not known whether the

species occurs there today. The few scattered records

in the Platte River system in Colorado and Wyoming

are documented by Ellis (1914) and Simon (1946).

The occurrence of the hornyhead chub in the upper

Cheyenne system of Wyoming (two plots, Figure 8)

is based on several specimens. Nocomis biguttatus has

some populations in northwest Iowa and southeast

South Dakota of the Missouri drainage.

Farther west across the Continental Divide in the

Colorado drainage, Cope and Yarrow (1875:651) reported Nocomis biguttatus, based on collections taken

by H. C. Yarrow and H. W. Henshaw (Wheeler Survey) in 1872, and the locality was given as Harmony,

Utah. Two extant collections of Yarrow and Henshaw,

USNM 16986 (8 specimens) and ANSP 19854 (1

specimen), were examined by us and these represent

Nocomis biguttatus. This locality is within the hydrographic boundary of ancient Lake Bonneville, between

the southern boundary of Lake Bonneville and the

headwaters of the Virgin River (R. R. Miller, personal

communication), a present tributary of the Colorado

River. Miller and Hubbs (1960:34) consider the locality as unquestionably erroneous and we concur,

because extensive field work by them throughout the

Great Basin has never revealed any Nocomis. Miller

and Hubbs (1960) also cite other erroneous locality

data associated with collections of the Wheeler Survey

of 1871-1874.

The hornyhead chub is widely distributed within

the glacial regions of the upper Mississippi River drainage. It is largely absent from the Driftless Area of Wis-
NUMBER 91 21

consin (Greene 1935:75, Map 26), as well as the

larger western rivers. It is widespread in the upper Red

River of the North drainage but apparently absent in

the Lake of Woods drainage, both of the Hudson Bay

basin. In the northern Ohio River basin Nocomis

biguttatus is widely distributed, but avoids the nonglaciated areas. The species has a restricted distribution

in the Allegheny River system of northwestern Pennsylvania. It is absent in the more upland sections of the

Allegheny and Monongahela River systems of western

Pennsylvania.

Lachner and Jenkins (1967:576) reported Nocomis

biguttatus south of the Ohio River in Kentucky based

on two collections from Elkhorn Creek, Franklin

County, lower Kentucky River drainage. Three additional collections have been examined from Elkhorn

Creek or its South Fork, UL 10479, 12465, and 12620.

These five collections are represented on Figure 8 by

a single plot. We suspect that this isolated population

is not natural because of the absence (but high survival

potential) of the species elsewhere in the system and

south of the Ohio drainage. The area has been an intensive angling site and the population probably represents introduction by bait fishermen or, accidentally,

through stocking programs or pond culture.

Several post-glacial routes assisted the entry of

Nocomis biguttatus into the Great Lakes drainage.

These routes are reviewed by Lachner and Jenkins

(1971). The hornyhead chub is widespread in drainages of southern Lake Ontario and all or most of

Lake Erie and Lake Michigan. It is present on the

Atlantic slope only in the Mohawk-Hudson drainage

of New York. It is absent from northern Lake Huron

and the Georgian Bay region. Its presence in the Lake

Superior area is restricted to streams of the southwestern portion.

The distribution and ecology of Nocomis biguttatus

is compared with N. effusus and N. micropogon by

Lachner and Jenkins (1967). Over much of its range,

east of the Mississippi River, N. biguttatus is sympatric

with N. micropogon. The ecology of N. biguttatus is

treated further in Lachner (1952). As a whole, the

species of the biguttatus group are tributary forms,

avoiding the main rivers. Clear water streams, smallto-moderate in size, with moderate-to-low gradients,

and with clean substrates of gravel, rubble, and some

sand are preferred. Generally, the preferred streams

have a moderate balance of riffles and pools, but long

pools of slack water often exist. Turbid waters or fine

silt-laden situations are usually not inhabited. Streams

with some aquatic vegetation appear to be preferred

more by iV. biguttatus and least by N. effusus.

The spawning behavior of Nocomis asper was observed by the authors at two typical habitats of the

Arkansas River drainage in Oklahoma—at Spavinaw

Creek, Delaware County, 7 June 1967, with water

temperature about 21° C. and at Flint Creek, Delaware County, 12 June 1967, with water temperature

about 21.5° C. These small, clear-water streams, 20 to

40 feet in width, have substrates of 70 to 95 percent

small-to-large gravel, the remainder of the bottom being

sand and rubble. The riffles are shorter in length than

the pools; the linear relationship is about 1:2. Most

of the riffles are about one-half to two feet in depth,

the slack water about two feet deep and the pools

three to four feet in depth, the deepest exceeding five

feet. The riffles are generally shorter in length than

the width of stream. Many nests of TV. asper were completed, located in the moderately flowing waters, at

the head of riffles, and in pools. The active nests,

where spawning was observed, also were occupied by

the spawning cyprinids Notropis pilsbryi and Dionda

nubila. The common stream inhabitants in Spavinaw

Creek were, in addition to TV. asper, the cyprinids

Dionda nubila and Notropis pilsbryi, the cottoid Cottus

carolinae, the smallmouth bass Micropterus dolomieui, and the percid fishes Etheostoma flabellare

lineolatum and Etheostoma spectabile.

The general habitat and ecology of Nocomis asper

elsewhere in the Ozark upland of the Arkansas River

drainage, particularly in the Neosho River system, is

described in relation to other fishes and problems by

Cross (1954), Minckley and Deacon (1959), Deacon

and Metcalf (1961), Branson (1967), and Cross and

Braasch (1969).

Evolution and Zoogeography

We have postulated (Lachner and Jenkins 1967) that

the biguttatus species group is probably primitive

within the genus, the assumption based mainly on the

general tuberculation pattern of the head and the

presence of two rows of pharyngeal teeth. A biguttatus

stock (s) was probably the precursor of the three groups

of Nocomis. The adaptive specialization of head tuberculation among the species of the micropogon and

leptocephalus groups involves elaboration and/or reductions of tubercle number, size, and distribution. The

head tuberculation within the biguttatus group is
22 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

about the same in the three species in regard to size,

distribution, and numbers when related to body length.

The minor tooth row of the pharyngeal arch is

absent in the micropogon and leptocephalus groups

and the loss is considered a derived condition. The

primitive condition of two tooth rows, 1,4—4,1, persists in Nocomis biguttatus and N. asper, but the minor

row is absent in N. effusus. The loss is regarded as a

development independent to the loss in the micropogon and leptocephalus groups.

The evolution of the three groups of Nocomis are

further compared and discussed by Lachner and

Jenkins (1967, 1971). Within the biguttatus species

group the body tuberculation in N. asper and N. effusus possibly represents evolution of another type of

tubercle pattern, restricted entirely to this group and

these two species of Nocomis. N. asper has more tubercles per tuberculate scale, laterally, on the side of the

body than N. effusus. The occurrence of tubercles on

the nape and on the scale rows above the lateral line

is more widespread in N. asper compared with N.

effusus. The body tubercles are much smaller in N.

asper than those of N. effusus. The reduction in tubercle numbers per scale and distribution on the body,

and the increase in tubercle size in N. effusus is regarded as a derived condition and correlates with the

evolutionary trends of head tubercle development in

the other groups of Nocomis. N. biguttatus is probably

the more primitive of its species group, having a general tubercular pattern only on the head. N. effusus,

because of its reduced dentition and specific body

tubercle pattern, is placed at the advanced end of the

biguttatus line. It also has the finest scales, narrowest

scale margins, and shows the least development of the

dark lateral band. N. asper is intermediate between N.

biguttatus and N. effusus in character development,

having a close affinity to N. effusus in its body tuberculation, and a close affinity to N. biguttatus in its coarser

scales, dark lateral body band, well-developed red postocular spot, and two rows of pharyngeal teeth.

The zoogeography of the eastern and southern forms

of Nocomis are discussed by Lachner and Jenkins

(1971) and Lachner and Wiley (1971). The occurrence of the wide-ranging N. micropogon and its distributional relationships with iV. effusus in the southwestern Ohio River basin is treated by Lachner and

Jenkins (1967). The interesting aspects of the zoogeography of the biguttatus species group is that two

of the species, N. asper and N. effusus, have restricted

distributions and have been long isolated by a vast

lowland; the nominal form is extremely wide ranging.

The three species are allopatric.

Nocomis effusus probably evolved within the region

of the Cumberland, Green, and lower Tennessee drainages. It is unlikely that it had a much wider range

because of its inability to traverse the Mississippi River

valley. Its preference for moderate-to-low-gradient

streams inhibited upstream movement. The closest

relative and probable ancestor of N. effusus, N. asper,

is not far west of the range of N. effusus, in the Ozark

region of the Arkansas River drainage and a restricted

portion of the Red River drainage. The lower portions

of the Mississippi River tributaries below the mouth

of the Tennessee River are not inhabited by members

of the biguttatus species group. The range of N.

biguttatus begins north of that of N. asper and is largely

north and west of N. effusus.

The Ozark upland has additional faunal relationships with the Tennessee and Cumberland drainages,

many species of which have almost always been confined to these two areas. Stages of main river development have provided means for species to establish a

southern trans-Mississippi River distribution, and for

isolation and subsequent differentiation on either side

of the river. Trans-Mississippi dispersal of many upland species was probably quite limited and, once a

large river was transversed, they would tend to seek

conditions upstream within newly occupied systems.

The important early relations among the Mississippi

and Ohio Rivers and some of their main tributaries are

discussed by Fenneman (1938:87-90) . (Also, see

Figure 30 of Lachner and Jenkins 1971). The Ohio

River once entered the Mississippi appreciably southward of the present mouth of the Ohio. The point of

juncture was assumed to have been somewhat below

Helena, Arkansas, which is about fifty air miles above

the mouth of the Arkansas River. At about that time,

the Tennessee River had a more southern confluency

with the Ohio, and the Cumberland was probably a

tributary of the former. These conditions were extant

during part of the Pleistocene, presumably until nearpresent relations were established in late Pleistocene.

Large rivers that were probably often turbid in the

past, as the Mississippi, are regarded as both barriers

to dispersal for upland, clear-stream fishes, and/or as

limited, direct routes of dispersal.

The species of Nocomis distinctly disfavor ecological

conditions that were probably present in the region of
NUMBER 91

the lower Mississippi, Ohio, and Tennessee Rivers.

Assuming N. effusus was derived from N. asper stock,

however, there had to be eastward dispersal from the

Ozark region into the southwestern Ohio River basin.

It is most probable that such dispersal occurred before

post-Pleistocene conditions. From the mouth of the

Arkansas River to the present mouths of the Tennessee

River and Cumberland River involves upriver movement over a considerably greater distance and through

conditions probably more difficult than those extant

when the rivers were confluent farther south. In addition, the evolution of N. effusus probably required a

greater time span than the age of the present drainage

relationships.

Dispersal of Nocomis effusus among the three drainages of the southwestern Ohio basin was through main

rivers and/or stream capture. It is possible that N. effusus used the Ohio River after the close of the Pleistocene, as mouths of the Tennessee, Cumberland, and

Green drainages are close to each other. They may

have been closer or formed a single river during earlier

stages of the formation of the Ohio basin. The fact

that N. effusus is known from the lower Tennessee and

Cumberland drainages lends credence to river dispersal.

It would be more presumptuous to assume that both

Nocomis asper and N. effusus were derived independently from a biguttatus-type stock. If so, the invasion

of biguttatus stock into the southwestern Ohio basin

would not be difficult to envision.

Problems related to the usage of stream capture in

zoogeographic considerations are discussed by Lachner

and Jenkins (1971). Although the known geological

evidence for stream captures in the southwestern Ohio

basin is meager, Wright (1936:246) stated that evidence of capture disappears with active dissection of

the capture area. When geological evidence for stream

capture is not ctied below, the possibility of stream

capture is still invoked when biological evidence exists,

and the streams involved are adjacent to each other.

The drainage in which Nocomis effusus evolved is not

known. Stream capture, however, probably occurred

between the Cumberland and Green and the Cumberland and Tennessee drainages, thus permitting crossing

of their divides. Considerable portions of both the

Green River and Barren River systems, Green drainage, are adjacent to the range of iV. effusus in the Cumberland. Campbell (1896:671-672) stated that these

divides have migrated toward the Cumberland. Such

migration probably involved stream capture. TV. effusus

23

would likely have been transferred during headwater

capture since it typically inhabits small streams. Many

additional small and moderate stream species are

shared by the Cumberland and Green drainages. There

also are close fanual relationships between the Cumberland and Tennessee drainages. One theater of

stream capture may have been in their lower portions

where the Duck River system of the Tennessee is

bounded almost entirely on the north by the

Cumberland.

Nocomis asper probably evolved in the Ozark plateau

of the Arkansas River drainage. It could have been

more widespread at one time, as evidenced by relict

populations at Turkey Island, western Arkansas drainage, in the Blue River of the Red River drainage, and

by the population in the upper Neosho River system of

Kansas. The occurrence of these relict populations is

interestingly paralleled by at least one species, N.

pilsbryi. Although the Arkansas and White drainages

have closely adjacent headwater tributaries and their

mouths are practically together, there is no known recent exchange of Nocomis between these drainages.

The Nocomis forms from the Arkansas River and

White River drainages have many characters common

to each other. We suspected intergradation in body

tuberculation and acquired large specimens needed to

solve this problem. None from the White River drainage showed any evidence of body tuberculation. Other

characters were also found to have differentiated from

those of the Arkansas drainage. Drainage exchanges,

however, between the White River and the Arkansas

River are suggested by Hubbs and Moore (1940:95)

involving Notropis pilsbryi, and by Branson (1964:

746) involving Notropis galacturus; Branson (1967:

148-152) discusses stream piracy and possible faunal

exchanges between these two drainages. Nocomis does

not appear to be involved in any recent White-Arkansas

drainage exchange for the differentiation of the two

forms is complete and constant in all tuberculate specimens.

The population of Nocomis biguttatus in the White

drainage is morphologically similar to that of the Missouri basin. The distribution of the hornyhead chub in

the Missouri basin consists of scattered, local populations, some of which are at a low level of survival, and

others are known only by collections of early explorers.

The present range of N. biguttatus in the Missouri

basin indicates an early, wider distribution. A progressive restriction in the distribution is attributed to the
24 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

erosional history of the area, recent agricultural practices, and to disfavorable climatic conditions.

The present distribution of Nocomis biguttatus indicates that refugia existed south of the glacial limits

in the Mississippi-Missouri basins during Pleistocene

times. With glacial retreat, N. biguttatus invaded the

upper Mississippi and Ohio basins. Its entrance in the

Great Lakes at several different, broad postglacial connections and times, and entry into The Red River of

the North, is discussed by Greene (1935), Radforth

(1944), Gerking (1945), Underhill (1957), Trautman (1957), Hubbs and Lagler (1958) and Bailey

and Allum (1962). The absence of N. biguttatus from

above the falls of the Genesee River system in New

York and in the upland Allegheny River system indicates that it entered the Lake Ontario drainage from

the west rather than through the Allegheny-Genesee

(Cuba) postglacial outlet. Entry of N. biguttatus into

the Mohawk-Hudson drainage was probably during

the Mohawk glacial outlet. Although N. biguttatus

and N. micropogon today are sympatric over extensive portions of their ranges, N. biguttatus probably

had central basin refugia during glacial times and

N. micropogon had a more easterly refuge (Lachner

and Jenkins 1971: Figure 30).

Literature Cited

Bailey, R. M., and M. O. Allum

1962. Fishes of South Dakota. Miscellaneous Publications, Museum of Zology, University of Michigan,

119: 1-131.

Branson, B. A.

1962. Observations on the Breeding Tubercles of Some

Ozarkian Minnows with Notes on the Barbels of

Hybopsis. Copeia, 3: 532-539.

1964. Additions to the Known Kansas Fish Fauna.

Transactions of the Kansas Academy of Science,

66 (4): 745-746.

1967. Fishes of the Neosho River System in Oklahoma.

The American Midland Naturalist, 78 (1): 126-

154.

Campbell, M. R.

1896. Drainage Modifications and Their Interpretations. Journal of Geology, 4: 567-581, 657-678.

Cleary, R. E.

1956. The Distribution of the Fishes of Iowa. Pages

267-324 in J. R. Harlan and E. B. Speaker, Iowa

Fish and Fishing. Third edition. State Conservation Commission, Des Moines, Iowa.

Cope, E. D.

1864. Partial Catalogue of the Cold-blooded Vertebrata

of Michigan. Proceedings of the Academy of

Natural Sciences of Philadelphia, 16: 276-285.

Cope, E. D., and H. C. Yarrow

1875. Report upon the Collections of Fishes Made in

Portions of Nevada, Utah, California, Colorado,

New Mexico, and Arizona, During the Years 1871,

1872, 1873 and 1874. Report on the Geography

and Geology, Exploration and Survey West of the

100th Meridian (Wheeler Survey), 5: 635-703.

Copes, F. A., and R. A. Tubb

1966. Fishes of the Red River Tributaries in North

Dakota. Contributions of the Institute for Ecological Studies, The University of North Dakota,

1: 1-26.

Cross, F. B.

1954. Fishes of Cedar Creek and the South Fork of

the Cottonwood River, Chase County, Kansas.

Transactions of the Kansas Academy of Science,

57 (3): 303-314.

1967. Handbook of Fishes of Kansas. Contribution from

the State Biological Survey of Kansas and the

University of Kansas Museum of Natural History, Miscellaneous Publication, 45: 1-357.

Cross, F. B., and M. Braasch

1969. Qualitative Changes in the Fish-fauna of the

Upper Neosho River System, 1952-1967. Transactions of the Kansas Academy of Science, 71 (3) :

350-360.

Davis, B. J., and R. J. Miller

1967. Brain Patterns in Minnows of the Genus Hybopsis

in Relation to Feeding Habits and Habitat.

Copeia, 1:1-39.

Deacon, J. E., and A. L. Metcalf

1961. Fishes of the Wakarusa River in Kansas. University of Kansas Publications, Museum of Natural

History, 13 (6) :311-322.

Ellis, M. M.

1914. Fishes of Colorado. University of Colorado

Studies, 11 (1): 1-136.

Evermann, B. W.

1918. The Fishes of Kentucky and Tennessee: A Distributional Catalogue of the Known Species. Bulletin

of the United States Bureau of Fisheries, 35:295-

368.

Evermann, B. W., and W. C. Kendall

1895. A List of the Fishes Known from the Vicinity of

Neosho, Missouri. Bulletin of the United States

Fish Commission, 14 (1894) :469-472.

Fenneman, N. M.

1938. Physiography of Eastern United States. 714 pages.

New York: McGraw-Hill.

Forbes, S. A., and R. E. Richardson

1920. The Fishes of Illinois. Second Edition. Division

of Natural History Survey, State of Illinois, Springfield. 357 pages.

Fowler, H. W.

1918. A Review of the Fishes Described in Cope's Partial

Catalogue of the Cold-blooded Vertebrata of Michigan. Occasional Papers of the Museum of Zoology, University of Michigan, 60:1-51.
NUMBER 9 1 25

Gerking, S. D.

1945. Distribution of the Fishes of Indiana. Investigations of Indiana Lakes and Streams, 3 (1): 1—137.

Gilbert, C. R.

1964. The American Cyprinid Fishes of the Subgenus

Luxilus (Genus Notropis). Bulletin of the Florida

State Museum, Biological Sciences, 8 (2) :95-194.

Girard, C.

1856. Researches upon the Cyprinoid Fishes Inhabiting

the Fresh Waters of the United States of America,

West of the Mississippi Valley, from Specimens in

the Museum of the Smithsonian Institution. Proceedings of the Academy of Natural Sciences of

Philadelphia, 8:165-213.

Greene, C. W.

1935. The Distribution of Wisconsin Fishes. 235 pages.

Madison: State of Wisconsin Conservation Commission.

Hall, G. E.

1952. Observations on the Fishes of the Fort Gibson and

Tenkiller Reservoir Areas, 1952. Proceedings of

the Oklahoma Academy of Science, 33:55—63.

Hinks, D.

1943. The Fishes of Manitoba. Department of Mines

and Natural Resources, Province of Manitoba, 102

pages.

Hubbs, C. L.

1926. A Check-List of the Fishes of the Great Lakes and

Tributary Waters, with Nomenclatorial Notes and

Analytical Keys. Miscellaneous Publications, Museum of Zoology, University of Michigan, 15:1—77.

Hubbs, C. L., and K. F. Lagler

1958. Fishes of the Great Lakes Region. Cranbrook Institute of Science, Revised Edition, Bulletin No.

26. 213 pages.

Hubbs, C. L., and G. A. Moore

1940. The Subspecies of Notropis zonatus, a Cyprinid

Fish of the Ozark Upland. Copeia, 2:91-99.

Hubbs, C. L., and A. I. Ortenburger

1929. Fishes Collected in Oklahoma and Arkansas in

1927. Publications of the University of Oklahoma

Biological Survey, 1 (3):47-112.

Jordan, D. S., and S. E. Meek

1885. List of Fishes Collected in Iowa and Missouri in

August, 1884, with Descriptions of Three New

Species. Proceedings of the United States National Museum, 8(1 ) :1-17.

Keleher, J. J.

1956. The Northern Limits of Distribution in Manitoba

for Cyprinid Fishes. Canadian Journal of Zoology,

34:263-266.

Kirtland, J. P.

1840. Descriptions of the Fishes of the Ohio River and

Its Tributaries. Boston Journal of Natural History^ (3):338-352.

Lachner, E. A.

1952. Studies of the Biology of the Cyprinid Fishes of the

Chub Genus Nocomis of Northeastern United

States. American Midland Naturalist, 48 (2):

433-466.

Lachner, E. A., and R. E. Jenkins

1967. Systematics, Distribution, and Evolution of the

Chub Genus Nocomis (Cyprinidae) in the Southwestern Ohio River Basin, with the Description of

a New Species. Copeia, 3:557-580.

1971. Systematics, Distribution, and Evolution of the

Chub Genus Nocomis Girard, of Eastern United

States, with Descriptions of New Species. Smithsonian Contributions to Zoology, 85: 97.

Lachner, E. A., and M. L. Wiley

1971. Populations of the Polytypic Species Nocomis leptocephalus (Girard) with a Description of a New

Subspecies. Smithsonian Contributions to Zoology, 92: 35.

Linder, A. D.

1955. The Fishes of Blue River in Oklahoma with Descriptions of Two New Percid Hybrid Combinations. American Midland Naturalist, 54 (1):

173-191.

Meek, S. E.

1891. Report of Explorations Made in Missouri and

Arkansas During 1889, with an Account of the

Fishes Observed in Each of the River Basins Examined. Bulletin of the United States Fish Commission, 9 (1889): 113-141.

1894. Report of Investigations Respecting the Fishes of

Arkansas, Conducted During 1891, 1892, and 1893,

with a Synopsis of Previous Explorations in the

Same State. Bulletin of the United States Fish

Commission, 14 (1894) :67-94.

Metcalf, A. L.

1966. Fishes of the Kansas River System in Relation to

Zoogeography of the Great Plains. University of

Kansas Publications, Museum of Natural History,

17 (3):25-189.

Miller, R. R., and C. L. Hubbs

1960. The Spiny-rayed Cyprinid Fishes (Plagopterini) of

the Colorado River System. Miscellaneous Publications, Museum of Zoology, University of Michigan, 115:1-39.

Minckley, W. L., and J. E. Deacon

1959. Biology of the Flathead Catfish in Kansas. Transactions of the American Fisheries Society, 88:344-

355.

Radforth, I.

1944. Some Considerations on the Distribution of Fishes

in Ontario. Contributions Royal Ontario Museum

of Zoology, 25:1-116.

Rafinesque, C. S.

1820. Ichthyologia Ohiensis. Reprinted with Biographic

and Supplemental Notes by R. E. Call, 1899. 172

pages. Cleveland, Ohio: Burrows Bros.

Raney, E. C.

1938. The Distribution of the Fishes of the Ohio Drainage Basin of Western Pennsylvania. Cornell University thesis. 102 pages.
26

Reno, H. W.

1969. Cephalic Lateral-line Systems of the Cyprinid

Genus Hybopsis. Copeia 4:736-773.

Simon, J. R.

1946. Wyoming Fishes. Bulletin Wyoming Game and

Fish Department, Cheyenne, 4:1-129.

Simpson, G. G., A. Roe, and R. C. Lewontin

1960. Quantitative Zoology. Revised Edition. 440

pages. New York: Harcourt, Brace & Company.

Taylor, W. R.

1954. Records of Fishes in the John N. Lowe Collection

from the Upper Peninsula of Michigan. Miscellaneous Publications, Museum of Zoology, University of Michigan, 87:1-50.

SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

Trautman, M. B.

1957. The Fishes of Ohio. 683 pages. Columbus: Ohio

State University Press.

Underhill, J. C.

1957. The Distribution of Minnesota Minnows and Darters in Relation to Pleistocene Glaciation. Occasional Papers, Minnesota Museum of Natural History, 7:1-45.

Wright, F. J.

1936. The New Appalachians of the South: Part 2, South

of the New River. Dennison University Bulletin,

Volume 36, Science Laboratory Journal, 31:93-

142.

US. GOVERNMENT PRINTING OFFICE :1971 O-4I6-00 9
Index

Adaptive specialization (tuberculation), 21-22

Allometric growth, 18

asper, Nocomis

coloration, 8, 18

comparison, 15—18

diagnosis, 4

distribution, 14, 19-21

ecology, 19-21

etymology, 9

evolution, 21-23

growth, 9, 16

key, 3

meristic characters, 6

morphology, 4

nuptial crest, 8

pharyngeal dentition, 8

reproduction, 9, 21

tuberculation, 6,15, 22

zoogeography, 21-24

biguttata, Hybopsis, 3, 19

Biguttatus group, 2

comparison of species, 15

key, 3

biguttatus, Hybopsis, 3, 19

biguttatus, Nocomis

coloration, 18

comparison, 15—18

diagnosis, 15

distribution, 13-14, 19-21

ecology, 20-21

evolution, 21-24

key, 3

map, 14

nomenclature, 10—12

specimens studied, 12-13

tuberculation, 15, 22

zoogeography, 21-24

biguttatus, Semotilus, 10

Biguttatus stock, 21-24

Body size

comparison, 15

relationship with head length, 18

Body tuberculation. See tuberculation.

Cephalic tubercles. See tuberculation.

Ceratichthys

cyclotis, 10-11

micropogon, 10, 12

stigmaticus, 10

Coloration

asper, 8

Comparison of species, 18

Comparison of species, 15-18

cyclotis, Ceratichthys, 10-11

Dionda nubila, 21

Distribution, 19-21

Distribution map, 14

Drainage exchanges, 22—23

Ecology, 19-21

effusus, Nocomis

coloration, 18

comparison, 15—18

distribution, 14, 19-21

ecology, 19-21

evolution, 22-23

key, 3

tuberculation, 15, 22

zoogeography, 22—23

Etheostoma flabellare lineolatum, 21

Etheostoma spectabile, 21

Etymology, 9

Evolution, 21-24

Growth, 9, 18

Head tubercles. See tuberculation.

Holotype, 3

Hornyhead chub, 3, 10

Hybopsis

biguttata, 3, 19

biguttatus, 3, 19

kentuckiensis, 3, 10

Hybrid, 10

kentuckiensis

Hybopsis, 10

Luxilus, 10

Key, 3

Lectotype, 10-11

Luxilus kentuckiensis, 10

Methods, 2

micropogon

Ceratichthys, 10, 12

Nocomis, 10, 12,22,24

Micropterus dolomieui, 21

nebrascensis, Nocomis, 10

Nocomis

asper, 3-10,15-18

biguttatus, 3, 10-15, 15-18

effusus, 3,15-18

micropogon, 10, 12, 22, 24

nebrascensis, 10

Nocomis micropogon X Notropis cornutus, 10

Notropis

galacturus, 23

pilsbryi, 19-21

Nuptial crest, 8

Nuptial tubercles. See tuberculation.

27
2

8

Objectives, 1

Paratypes, 3

pilsbryi,Notropis, 19-21

Pleistocene

conditions, 22-23

refugia, 24

Redspot chub, 3

Redtail chub, 3

Refugia, Pleistocene, 24

Regression equations, 16

Relict populations, 23

Reproduction, 9

Semotilus biguttatus, 10

Species group

Nocomis biguttatus, 2, 15, 21-24

Nocomis leptocephalus, 1, 21-22

Species group)—Continued

Nocomis micropogon, 1, 21-22

Specimens studied, 3-4, 12-13

Squamation, summary, 16

stigmaticus, Ceratichthys, 10

Stream capture, 23

Swelling, 8

Techniques, 2

Tuberculation

adaptive specialization, 21

body 7, 15, 17-18,22

cephalic, 6-8, 9, 15

nape, 16, 22

supernumerary, 11,15

Vertebrae, 7

Zoogeography, 21-24
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