Bull. Natn. Sci. Mus. , Tokyo, Ser. B, 25( I), pp. 5- 27, March 23, 1999

Contribution to the Desmid Flora of Papua New Guinea
A. A. Gontcharov 1*, Masayuki Watanabe 2 and Makoto M. Watanabe 11Environmental Biology Division, National Institute for Environmental Studies,16- 2 Onogawa, Tsukuba, lbarak i 305- 0053 , Japan2
Deparlment of Botany, National Science Museum,4- 1- 1 Amakubo, Tsukuba, lbarak i 305- 0005 , Japan

Abstract An investigation has been made into the desmid flora of Mt. Albert Edward and it's surroundings, Papua New Guinea . In 80 samples from different localities 80 taxa of 13 genera were revealed . For 23 of them this is a first finding in PNG.
Zygospores of 8 species are recorded and illustrated, spores of Staurastrum contectum var. aviceps have not prev iousl y been reported in th e literature. Two taxa, Cosmarium porosum Gontcharov et M. Watanabe sp. nov. and S. capitulum va r. spiniferum Gontcharov et M. Watanabe var. nov. , are described . The morphology of some
spec ies is discussed.
Key words:

Desmids, flora, new records, Mt. Albert Edward, Papua New Guinea.

Although the number of papers dea ling with the desmid algae from Papua New
Guinea is relatively small , about 500 of taxa have been revealed there so far. The
most extensive list of species including 427 taxa was presented by Vyverman ( 1991 ).
His study covered a wide range of habitats and provides valuable information about
desmid diversity of this part of the world.
Prior to his investigation considerable algal collections were made in Papua New
Guinea by the members of four botanical and microbiological expeditions of the National Science Museum , Tokyo in 1969- 1975 . 345 samples of freshwater algae werecollected by Dr. Takaaki Yamagishi in 1973- 1974 and 231 samples by Masayuki
Watanabe in 1975 . Only part of this material was identified and the results published(Yamagishi, 1975 ; M . Watanabe et al., 1979; M. M. Watanabe et al. , 1979; Yamagishi & M. Watanabe , 1979; Kumano, 1983 ; Kumano & M. Watanabe, 1983 ; Yamagishi & Kanetsuma , 1990).
Eighty samples used in the present study were collected by M. W. during an ascent of Mt. Albert Edward (3996 m a.s.l.; figs. 1- 3) which is located about 60 km
north of Port Moresby, the capital of Papua New Guinea. Although the samples wererelatively poor regarding the desmids, some interesting species were revealed .
Among them two taxa are believed to be new for science and two species are unidentified so far.
*To whom correspondence should be add ressed.

6

A. A. Gontcharov, Masayuki Watanabe and Makoto M. Watanabe

Fig. I. Route map from Woitare to Mt. Albert Edward. A dotted line: route; thick line: mountainridges; thin branching lines: river systems; a dashed line surrounding the mountain: a contourof 3500 m above sea level , I, 2, 3: campsites.

-· - ~~~·\ ..
..

~

..#

r:;::;; •
~

~

~
(

Fig. 2. A panoramic view from camp 3 shows the a glacial landform is gently sloping and covered with grasses.

Fig. 3. A panoramic view from camp 3 shows the several forest patches are scattered among
grassland.

Contribution to the Desmid Flora of Papua New Guinea

7

Samples N51245- 51252, Woitape, 1500m a.s.l., Oct. 15- 16, 1975, evergreen
forest; N51253- 51260, Woitape-camp I, 2600 m a.s.l., Oct. 18- 21 , 1975, evergreen
forest ; N51261 - 51297, camps 1- 2, 3100m a.s.l. , Oct. 22- 26, 1975, arid grasslandwith tree-ferns scattered and some bogs; N51298- 51315 , camps 2- 3, 3600 m- 3800 m
a.s.l. , Oct. 27- 29, 1975, grassland with numerous small lakes and some bogs.
The algae were collected by pipette from aquatics or taken manually from theupper sediment layer. Samples were examined under the Olympus BH-2 light microscope. Microphotographs were taken with Olympus C-35AD-4 camera. Drawings
were made with a camera lucida.
For scanning electromicroscopy, algae were treated with 2% glutaraldehyde incacodylate buffer for 2 h at room temperature and washed several times with distilledwater. Thereafter, cells were post-fixed with I% Os0 4 in the buffer for 1 h, rinsed
with distilled water and dehydrated in the alcohol series. Finally cells were dried at
critical-point in liquid C0 2 . After coating with gold samples were examined with Hitachi Stereoscan S-4200.
The enumeration of the species is in accordance with the system of Ruzicka( 1977) except the genus Staurodesmus Teil. The arrangement of the species withineach genus is alphabetical. Taxa which had not previously been recorded from PNG
are marked with an asterisk.
All dimensions are given in micrometers; the following abbreviations are used:
L=length of cell , W = width of cell, T = thickness of cell, ! = breadth of isthmus, csp=with spines, ssp = without spines, cpr = with processes, spr=without processes.
Species enumeration
Order Desmidiales
Family Peniaceae Haeckel
Penium Breb. ex Ralfs
PI. I, fig. 2.
P. cylindrus Ehr. ex Ralfs
L 32.5 pm , W 15 pm.
P. spirostriolatum Bark.
PI. I, fig. I.
L 155pm, W 22 .5pm .
Penium sp.
PI. I, fig. 3.
L42 .5pm, W 17.5pm.
Similar alga was reported in PNG by Vyverman ( 1991 ). He discussed it's possible affiliation but data on the zygospores morphology is needed for precise identification .
Family Closteriaceae Pritch.
Closterium Nitzsch ex Ralfs
Cl. abruptum W. West

PI. I, fig. 10.

8

A. A. Gontcharov, Masayuki Watanabe and Makoto M. Watanabe

W 170- 225,um, W 15- 22.5,um, Ap 7.5- lO,um.
This taxon is very similar with Cl. nilsonii Borge and only the absence of striates differentiates it. Our specimens are characterised by smooth yellowish cell wallwith girdle bands.
Cl. closterioides (Ralfs) Louis et Peeters
PI. I, fig . 4.
L 110- 200 ,u m, W 25- 35 ,urn .
Cl. dianae Ehr. ex Ralfs
PI. I, fig . 7.
L 175 ,urn, W 5- 7.5 ,urn.
Cl.jennerii Ralfs
PI. I, fig. 8.
L 87.5 ,urn , W 12.5 ,urn .
Cl. moniliferum (Bory) Ehr. ex Ralfs
PI. VIII , fig. I.
W 235- 270 ,um, W 35- 50 ,urn.
Cl. navicula (Breb.) Liitkem.
PI. I, figs. 5, 6.
L 42.5- 77.5 ,urn, W I 0- 12.5 ,urn. Zygospore 30 ,urn long, 25 ,urn width.
*Cl. ralfsii Breb. ex Ralfs var. gracilius (Mask.) Krieg.
PI. I, fig. 11.
L 177.5- 232.5,um, W 12.5- 15,um.
Vyverman ( 1991) reported the type variety of this species in PNG . Our alga differs from it in it's smaller dimensions.
Cl. striolatum Ehr. ex Ralfs
PI. I, fig. 12.
L 215- 267 ,urn, W 25- 30,um , Ap 7.5- IO,um.
*Cl. tumidulum Gay
PI. I, fig. 9.
L 107.5- 117.5,um, W 17.5,um.
Family Desmidiaceae Ralfs
Haplotaenium Bando
H. minimum (Ralfs) Bando

PI. 11 , fig. 9.

L 112.5- 117.5 ,urn, W 12 .5- 13.8 ,urn.

Actinotaenium Teil.
*?A . cruciferum (De Bary) Teil.

PI. II , fig. 4; pi. IX, fig . 2.

L 12.5- 15,um, W 7.5,um .
A large amount of this small alga was found in sample 51308. The outline of it 'scell was somewhat different from that is typical in this species. All our specimens
have cylindrical cells with truncate apexes; median constriction is very shallow but
always evident. Despite this difference in cell morphology, it possesses stelloid
chloroplasts with one or two perinoid per cell what as usual for the species. Its cellwall looked smooth under LM but has irregularly arranged small pores (SEM, pi. 9,
fig. 2). This alga can be compared with Cosmarium subtilissimum G. S. West or C.
biobconicum Briihl. et Biswas.
Earlie A. crucife rum var. cruc1[erum f. latum Teil. was reported in PNG (Yamagishi & Kanetsuma, 1990).

Contributi on to th e Desmid Flora of Papua New Guinea

9

A. cucurbita (Breb.) Teil.

PI. 11 , figs. I, 2.
L 30-40 pm, W 15- 25 pm , I 13 .5- 20 pm .
This alga was one of the most common species in the studied samples. Cells
with bigger dimensions and subcircular semicells (pi. 2 : I) were common in somesamples from localities 2 and 3.
PI. 11 , fig . 3.
*A . obcuneatum (W. West) Teil. var. oravicum Ruzicka
L 22.5,um, W 12.5pm .
This taxon is not rare at the Far East and SE Asia, however, it is reported for the
first time in PNG .

Tetmemorus Ralfs ex Ralfs
T. laevis Kutz. ex Ralfs

Pl.I,fig. l3 .

L 112.5pm , W 25,um.

Euastrum Ehr. ex Ralfs*E. ansatum Ehr. ex Ralfs var. triporum Krieg.

PI. 11 , figs. I 0- 12; pi. IX, fig . I.
L 80- 90pm , W 37.5-40pm, I 12.5pm, T 25pm, Ap 22.5pm.
Under LM only a median basa l protrusion was seen in this alga, however, in a
few specimens two very slight protrusions opposite the upper lateral lobes were detectable as well. The size of th e lateral lobes was variable, sometimes the lateral sides
were nearly straight. Such characters as one basal protrusion and three pores per
semicell allow us to suppose affiliation of our specimens to E. akaiense Hinode (Hinode , 1955 , p. 80, pi. 4 : 1- 6), however, they have somewhat bigger dimensions. Hinode (1. c.) mentioned the similarity of his alga with E. sinuosum , but from our pointof view it is more similar to E. ansatum var. triporum and only one protrusion per
se mice ll differs it from the latter taxon .
Study under the SEM revealed two small protrusions at the base of the semi cell
besides a prominent supraisthmal one and confirmed the presence of two protrusions
on either side of the midregion (pi. 9, fig. I). The pattern of cell wall decoration of
our plant is similar to that reported in the type variety of the species, reticulate withpores of I, 2, 3 and 4 types (Neuhaus & Kiermayer, 1982). In var. triporum this reticulation seems to be more prominent. Three large pores are present at the midregionof the semicell. The central pore is surrounded by a somewhat elongated smooth area
and the same area is extended from the incision of the apical lobe. This feature is detectable under LM as well (pi. 2, fig. I 0).
The outline of the cell , total number of protrusions and large pores per semicell
in our alga correspond to those of E. ansatum var. triporum , whereas the four small
lateral protrusions, sometimes almost undetectable, presence of smooth channel likeareas, connected central pore and apical incision distingui shed it from the mentioned
taxon.
The variety under di sc ussion is reported for the first time in PNG. Vyverman

10

A. A. Go ntcha rov, Masayuki Wata nabe and Ma koto M . Wata na bc(1991, pi. 47, fig . 3) illustrated a cell of E. ansatum var. dideltiform e Ducell. withthree large pores per semicell what is not typical for this taxon but is a distinctive feature of var. triporum. However, the taxonomic importance of this character is questionable (Ruzicka , 1981 ). According to Neuhaus & Kiermayer ( 1982) the number ofthese pores in var. ansatum varies from I to 3.
PI. VIII , fig. 2.
E. bidentatum Nag.
L 55- 57.5,um, W 37.5-40pm, I 12.5pm.
*E. boldtii Schmidle
PI. II , fig. 14.
L 22 .5 pm, W 17.5 pm .
E. denticulatum (Kirchn.) Gay
PI. Il, fig. 13.
L 22.5- 25 pm, W 20- 22.5 pm .
E. gayanum De Toni
PI. Il , figs . 16, I 7.
L 12.5- 15 ,urn, W 10- 12.5 pm.
The expression of cell wall ornamentation was a variable character in our material. This taxon displace transitions to E. binale (Turp.) Ehr. ex Ralfs and it 's varieties
and the difference between these algae seems to be not clear.
*E. insulare (Wittr.) Roy
Pl.ll , fig . 7.
L 22 .5- 25 ,um, W 17.5- 22.5 pm .
*E. montanum W. et G. S. West
PI. Il , fig . 8.
L 22.5- 27.5 pm , W 17.5- 22 .5 ,um , I 5- 7.5 ,um.
*E. obesum Josh.
PI. 11 , fig. 5.
L 107.5- 120,um, W47.5- 50pm, 117.5,um,Ap22.5,um.
E. sinuosum Lenorm. ex Arch.
PI. II , fig. 6.
L 57.5 pm, W 30 ,um, I 10 pm.
*E. subalpinum Messik. var. crassum Messik.
PI. II , fig . 15 .
L 17.5- 22.5pm, W 15- 16,um, T I0- 12.5,um.
Cells with long apical lobes typical for the type variety of the species were seenin sample 51318. According to Ruzicka ( 1981) this variability brings into the question the difference between these two varieties.
A similar algae has been reported in PNG by Yamagishi & Kanetsuma (1990) as
E. subalpinum var. granulosum Gronbl.

Cosmarium Corda ex Ralfs
C. amoenum Breb. ex Ralfs var. mediolaeve Nordst.
L 47 .5 ,um, W 30 ,um, I 10 pm.
C. caelatum Ralfs
L 42.5 ,um, W 42.5 ,um, I 17.5 ,urn.
C. connatum Breb. ex Ralfs
L 47.5- 57.5 ,um, W 37.5-45 ,um, I 30- 35 ,um.
C. contractum Kirhn . var. ellipsoideum (Elfv.) W. et G. S.West
L 27.5- 35 pm , W 20- 25 ,um, I 7.5 pm.

PI. V, figs. 5, 6.
PI. V, fig. 9.
PI. Ill , fig. I .
PI. Ill , fig . 11 .

Contribution to the Des mid Flora of Papua New Guinea

C. crenatum Ralfs

11

PI. IV, figs . 17, 18.
L 27.5- 30.um , W 17.5- 22.5.um, I 7.5- 12.5.um.
C. decoratum W. et G. S.West
PI. V, figs. 3, 4
L 67.5- 75 .um, W 52.5- 60 .um, I 20 .um.
?C.javanicum Nordst.
PI. Ill , figs. 4, 5.
L 130- 137.5 .um, W 82 .5- 87.5 .um, I 37.5-47.5 .um.
This alga was found in small amounts in sample 51270. Its morphology corresponds to the diagnosis (Nordstedt, 1880, p. 7, pi. I : I 0) but we question it because
no cells with chloroplasts were observed. The taxon under discussion was similar to
C. ralfsii Breb. ex Ralfs var. montanum Racib. but this species distinguishes in the
structure of chloroplasts.
Our plant is characterised in it 's thick, obviously 2-l ayered, scrobiculate-punctate
cell wall. A similar cell wall structure was recorded in the species by Skuja ( 1949).
C. laeve Rabenh.
PI. IV, fig. 12.
L 20- 25 .um, W 15- 15.5 .um, I 5- 7.5 .um, T 12.5 ,um. Zygospores 27.5X25 ,um.
The shape of semicells varies from semicircular to subpiramidal but the notch at
the apex was always evident.
*C. lapponicum Borge
PI. Ill , fig. 2.
L 25 .um, W .um, T 12.5 .
Vyverman ( 1991) reported var. undulatum Borge in PNG . The difference between these two taxa seems to be minor (Prescott et al., 1981) and maintenance oflatter variety is questionable.
C. minimum W. et G. S.West
PI. IV, fig. 15.
L I0- 12.5,um, W IO.um, 16.um.
Characteristic specimens of this alga were rather common in many samples.
However, cells with somewhat retuse lateral sides, which is typical for C. norimbergense Reinsch var. depressum (W. et G. S. West) Krieg . et Gerloff, were observed in
the same localities.
*C. nasutum Nordst. var. nasutum f. granulata Nordst.
PI. VI, figs. 1- 3.
L 35- 50,um, W 25-40.um , I I0- 12.5.£1m.
Few zygospores were seen in sample 51268. The zygospores were spherical,
with swollen-based stout spines acute or bifurcate at the ends, about 9 of which canbe seen at the periphery; 27.5 .um in diameter without spines, 47.5 ,um with spines.
The dimension of the zygospores found were the same as described in this taxon(Forster, 1965). However, according to this author they have mamillate protuberances
furnished with a short uncinate spine. In our alga these protuberances are much
longer, like processes.
*C. nitidu/um De Not.
PI. IV, fig . 8.
L 47.5 ,um, W 32 .5 .um, I 20 .um.
The type variety of the species is reported for the first time in PNG. Earlier var.
javanicum Krieg. et Gerloff was recorded there (Vyverman, 1991 ).

12

A. A . Gontcha rov, Masayuki Watanabe and Ma koto M. Watanabe

PI. Vlll , fig . 10.
C. obliquum Nordst.
L20pm, W 15pm, I lOJ..Lm.
Cosmarium porosum Gontcharov et M. Watanabe sp. nov.
PI. IV, figs. 9- 11 ; pi. Vlll , fig . 12.
Diagnosis: Cellulae parvae, latitudine longitudinem fere aequante, leviter constrictae, sinu maxime late aperto. Semicellulae obtrapeziformes; marginibus lateralibus rectis, apice lato et recto, angulis apiculibus attenuatis, anguste rotundatis. Semicellulae a latere visae obtrapeziformes, apice truncato, a vertice visae transverse
hexagonales, extremis attenuatis. Membrana crassa, cum quinqui poris grandibus adapicem, uno ad centrum, quatuor ad angulorum lateralium. Chloroplastus monocentricus.
Dimensions: Longitudo 15- 17.5 J..Lm , latitudo 17.5 pm, isthmi latitudo 12.515 pm , crassitudo 10 pm .
Holotype: Tab. 8, fig. 12.
Cell is quadrangular, as broad as long, slightly constricted, the sinus widelyopen. Semicells inversely trapeziform, apex broad, straight or slightly convex, lateralsides straight or nearly so, apical angles somewhat attenuate , narrowly rounded; inlateral view semicells inversely trapeziform , with truncate apex , in vertical view cell
hexagonal, with attenuate ends. Cell wall rather thick , punctate, with a conspicuous
pore at the apex and similar pores within the apical margins near the lateral ends, intotal 5 large pores per semicell are present. Chloroplast with I pyrenoid. L 1517.5J..Lm , W 17.5pm, I 12.5- 15pm, T lOJ..Lm.
This characteristic alga was found in small amount in the samples collected at
locaity 3. The prominent pore pattern clearly differentiates it from other Cosmarium
species. The number of taxa of the genus possessing such large pores is rather limited
and there is no general tendency in these pores ' arrangement.
C. pseudarctoum Nordst.
PI. I!, fig . 18.
L 17.5- 20pm, W 10- 12.5pm, I 7.5- lOpm.
C. pseudoconnatum Nordst.
PI. Vlll , fig . 3.
L 57.5- 72 .5 pm, W 45- 52 .5 J..Lm, I 40-45 pm.
C. pseudoconnatum var. subconstrictum Jao
PI. Ill , fig. 2.
L 67.5- 72.5pm, W 40pm, I 35pm.
This alga has been reported in PNG by Kanetsuma & Yamagishi ( 1989a).
As a type variety of the species this taxon possesses four parietal chloroplasts ineach semicell , each with one pyrenoid. However, the elongated semicells with thebroadest part just above the isthmus distinguishes it from other infraspecific taxa ofthe species. Morphologically the plant under discussion is very similar to C. westii
Bern. , C. thwaitesii Ralfs and Actinotaenium capax (Josh.) Teil. var. minus (Schmidle) Teil. , however, mentioned taxa are distinct in their chloroplasts structure.
*C. pseudonitidulum Nordst.
PI. IV, figs. 6, 7.
L 45 pm, W 35 J..Lm , I 20 pm.

Contribution to the Desmid Flora of Papua New Guinea

13

In the specimens studied cell wall was distinctly but rather scarcely punctate. Allother features conform to the original diagnosis (Nordstedt, 1873: 16, pi. I: 4 ).
C. punctulatum Breb.
PI. IV, fig. 14.
L 20- 22.5 J..Lm , W 22.5 J..Lm , I 7.5 pm.
PI. Ill , fig. 3.
C. pyramidatum Breb. ex Ralfs
60- 80J.1m, W 35-42.5pm, 115- 17 J.lm , T 25pm.
C. quadratulum (Gay) De Toni var. applanum Insam et Krieg.
PI. IV, fig. 16.
L I 0- 12.5 pm, W 10 pm , I 6 pm. The zygospores are spherical, with numerous
short spines, about 12- 14 of which can be seen at the periphery, 15 J..Lm in diameter
without spines, 20- 22.5 pm with spines.
This taxon has been recorded in PNG (Kanetsuma & Yamagishi, 1989b). The
morphology of vegetative cells and zygospores of the specimens studied corresponds
well to their illustration of this taxon. It was very rare in our samples and only a few
cells were seen. This alga occurred in the same samples as C. minimum and due tothe morphological variability of the latter taxon their segregation was rather difficult.
C. quadratum Ralfs
PI. IV, fig . I.
L45- 55pm, W 25- 30pm , 112.5- 17 .5J..Lm.
C. guadrifarium Lund. var. octastichum (Nordst.) Forst.
PI. VI, figs. 4, 5, 12, 13 .
L 37.5-45 J.lm, W 32.5- 35 J.lm, I 10- 12.5 pm. The zygospore was subspherical,
black, with four produced subtruncate angles extended into the conjugating semicells, the angles of one end twisted into a plane at right angles to the other two,
45 J..Lm in diameter.
This species is distinct in it's pattern of cell wall decoration . Usually it possesses
15 to 17 emarginate warts at the lateral margins of semicell in 2- 3 intramarginalrows. The main portion of our alga is characterised by rows of flattened rather thenemarginate granules. This pattern of cell wall ornamentation is illustrated in the sametaxon by Thomasson ( 1963 ). This character seems to be very constant in the studied
populations and only a few spec imens with emarginate granules were seen. It distinguishes our specimens from the diagnosis but at the same time the pattern of decoration is typical for C. guadr!farium. Moreover, the morphology of the zygospores revealed in the samples corresponds to those reported in the species (Lundell, 1871;
Allorge, 1930).
*C. raciborskii (Racib.) Lagerh.
PI. IV, fig. 5.
L 47.5 pm, W 47.5 pm.
*C. reniforme (Ralfs) Arch. var. apertum W. et G. S. West
PI. V, fig . 7, 8.
L 42 .5 pm, W 45 J.lm , I 15 pm.
An open linear sinus was a constant feature of our plants and few specimens
with a closed sinus were observed. Among other taxa C. pseudobroomei Wolle var.
apertum Forst. possesses the same character but it differs from our alga in cell outline
and pattern of granulation.
In some specimens a hexagon punctata around each granule were seen. A simi-

14

A. A. Gontcharov, Masayuki Watanabe and Makoto M. Watanabe

lar pattern of cell wall decoration was depicted in the type variety of the species by
Schulz ( 1930, fig. 30) and Williamson ( 1996, fig. 8: 3). On the SEM photographs ofthi s species, presented by Coute & Tell ( 1981 , p. 6: 1, 2) this character is absent.
Punctulations around granules are typical for C. margaritatum (Lund.) Roy et Biss.,
however, the mentioned taxon has bigger dimensions and a different outline of semicells in face and vertical views. Croasdale & Flint ( 1988) stated that it always hasconvex sides in vertical view while alga from PNG has parallel sides.
PI. VIII, fig. 8.
C. sinostegos Schaarschm.
L 12.5- 15pm, W 15- 17.5pm, 12.5- 3.1pm.
PI. IV, fig . 13 .
C. sublateriundatum W. et G. S. West
L 30 pm, W 22.5 pm, I I 0 pm.
PI. Ill , figs. 6, 7.
C. tatricum Racib.
L 37 .5pm, W 25pm, I 17.5pm.
C. tenue Arch.
PI. Ill, figs . 8, 9.
L 20- 22.5 pm, W 17.5- 20 pm, I 6- 7.5 pm . Zygospores spherical, colourless,
25 pm in diametre.
Species is similar to C. melanosporum Arch. in morphology but distinguishes
from it in the colourless zygospores.
C. tinctum Ralfs
PI. VIII, fig. 4.
L 15- 22.5pm, W 12.5- 15pm, I 7.5- !0pm.
C. variolatum Lund. var. skujae Croasd.
PI. IV, figs . 2--4.
L 42 .5- 57 .5 pm, W 27.5-32 .5 pm, I 12.5 pm.
Williamson ( 1994) pointed out that the scrobiculated cell wall clearly differentiates the alga under discussion from C. pseudopyramidatum Lund. which has a comparable appearance. However, in PNG material transitional forms between these two
taxa were seen (pi. 4: 4). The same range of morphology has been mentioned in thisspeciees by Yamagishi & Kanetsuma ( 1990).
Cosmarium sp.
PI. V, figs . 1- 2; pi. IX, figs . 3, 4.
L I 02.5- 105 pm, W 62.5- 65 pm, I 20- 25 pm, T 45- 50 pm.
This large alga was present in large numbers in sample 51269 . It is very similar
to C. amoenum var. mediola eve in appearance and pattern of cell wall ornementation
but distinguishes in much bigger size. It has subrectangular semicells with narrowly
rounded basal angles, convex lateral sides and broadly rounded apexes. The cell wallis granulated with large somewhat elongated rounded granules di sposed in 18- 20
oblique and 12 horizontal rows, with punctata betwen the granules. In the central partof semi cells granules are reduced in size or sometimes only punctata are present. The
semicells are ovate in lateeral view, broadly elliptic in vertical view.
Among large-celled Cosmarium species with granulated cell walls C. amplum
Nordst. resembles our alga but it clearly segregates from it in the shape of the semicell in face and lateral views and in the uniformly granulated cell walls.

Contribution to the Desmid Flora of Papua New Guinea

15

Staurodesmus Teil.
*S. boergesenii (Messik.) Croasd.
PI. V I, fig. 8.
L 15- 17.5,um, Wssp 12.5- 15,um, Wcsp 17.5- 20,um, 17.5,um.
There are a number of small-sized species in the genus that our specimens resemble. However, inversely-trapeziform semicells with straight or slightly convex
apexes and relatively long parallel spines are more typical forS. boergsenii.
*S. isthmosus (Heimerl) Croasd .
PI. VI , fig. 7.
L 17.5,Um, Wssp 12.5- 15,um, Wcsp 20- 30,um, 14- 5,Um.
S. omearii (Arch.) Teil.
PI. VIII , fig. 9.
Lssp 17.5 ,urn, Lcsp 30 ,Urn, Wssp 12.5 ,Urn, Wcsp 25 ,urn, I 7.5 .urn.
S. pachy rhy nchus (Nordst.) Teil.
PI. VI, fig. 6.
L 25 ,urn, W 17 ,urn, l 6 ,urn.
Staurastrum Meyen ex Ralfs*S. capitulum Breb. ex Ralfs var. dimidio-minor Gronbl.
PI. VII, fig . 9; PI. VIII , fig. 7.
L 17.5 .urn, W 17.5 .urn.
This smaller variety of the species seems to be reported for the first time outside
N. America. It is characterised by smaller dimensions and a cell wall ornamented bya few rows of small granules around the processes and the isthmus. Croasdale &Gronblad ( 1964, pi. 17: 17) illustrated these granules in a circle around the isthmus
but in our specimens 4- 6 granules were disposed on ly under the processes with aclear break between them.
Staurastrum var. spiniferum Gontcharov et M. Watanabe var. nov.
PI. Vl, figs. 17, 18; pi. VIII , fig. 6.
Diagnosis: Varietas angulis apiculibus spiniferis a varietate nominata differt.
Dimensions: Longitudo 37.5 ,urn, latitudo sine processibus 15 ,urn, latitudo
cum processibus 25- 32.5 ,urn, isthmi latitudo I 0 ,urn.
Holotype: Tab. 8, fig. 6This alga was found in relatively large amounts in the samples 51268- 51271.
The out Iine of the cells and the pattern of cell wall ornamentation allow us to suppose
it's affiliation to S. capitulum. However, this species is characterised by rounded apical angles with a series of granules across them . In the specimens studied each angle
was tipped with a stout spine and had the same rows of acute granules or spines as reported in the species. No plants of any other morphology were observed. L 37.5 ,urn,
Wspr 15 ,urn, Wcpr 25- 32.5 ,urn, l 10 ,urn.
S. contectum Turner var. aviceps Krieg.
PI. VI, fig. 14- 16.
Lcsp 20- 25 ,urn, Wcsp 20- 25 ,urn, I 7.5 ,urn. Zygospores spherical , with shortrounded spines, 9- 12 of which can be seen at the periphery, 22 .5 ,urn in diameter
without spines, 30 ,urn with spines.
Among algae recorded from PNG S. guadricornutum Roy et Biss. var. simplex

16

A. A. Gontcharov, Masayuki Watanabe and Makoto M. Watanabe

Vyverman resembles our plant. Vyverman ( 1991) mentioned a similarity between
these two taxa but listed them separately in his paper. In our samples dichotypic cells
similar to those reported by this author also were observed. From our point of view itlinks S. contectum var. aviceps with S. quadrangulare (Bn~b.) Ralfs.
S. dilatatum Ehr. ex Ralfs
PI. VI , figs. 9, I 0.
L 20- 25 pm, W 20- 25 pm , I 7.5 pm.
?S.forficulatum Lund.
PI. VII, figs. 3, 4.
Lspr 25- 27.5 pm , Wspr 30- 32.5 pm , I 7.5- 10 pm.
We question this epithet because the morphology of our specimens does notcompletely agree with the diagnosi s. The apical processes are placed very close to
the secondary processes at the lateral sides and these four processes and the si mple
spines at the ventral margins of the semi cells form a circle around them.
Vyverman (I 99 I) mentioned some morphological variability of the species
under discussion and it's intermediate forms with S..fitrcatum (Ehr. ex Ralfs) Breb., S.
gutwinskii Bernard and their varieties. Perhaps S. senarium Ehr. ex Ralfs is also aclosely related taxon and practical definition of these taxa is always difficult.
S.furcigerum (Breb. ex Ralfs) Arch.
PI. VII, fig . 2.
Lspr 35- 37.5 pm , Lcpr 45- 55 pm , Wcpr 45- 55 pm , I 12.5- 15 pm.
S. inconspicuum Nordst.
PI. VI , fig . I I.
Lcpr 12 .5pm, Wcpr 12.5 pm , 16pm.
S. margaritaceum (Ehr.) Menegh. ex Ralfs
PI. VII , fig3. 7, 8.
L 27.5-40 pm , Wcpr 30-42.5 pm , I 7.5- 17.5 pm.
*S. muelleri Forst., morphae
PI. VII , figs. I 0, I I; pi. VIII , fig. 13 .
Lcpr27.5pm, Wcpr27.5pm , T 12.5 pm, I !Opm.
This remarkable alga was found in sample 51306. The cells are small, about aslong as broad, si ightly constricted and the sinus is rounded at the apex. The semi cells
are companulate, with a row of spines supraisthmally and the apex straight andsmooth. The processes are short, attenuate, tipped with 3-4 small teeth, with undulate margins and 3-4 transverse series of granules, the proximal granules are usuallyemarginate. In vertical view semicell is fusiform with undulate margins, and issmooth at the centre.
The dimensions of the specimens from PNG are somewhat bigger than indicatedin the diagnosis (Forster, 1964, p. 234, pi. I: 36, 3 7, pi. 2: 20, 21) and the sem icell s
have longer basal parts. However, the appearance of our alga and the pattern of it 'scell wall ornamentation are almost the same as described in the species under discussion. It seems to be the first report of this taxon outside Africa.
S. punctulatum Breb. ex Ralfs
PI. VII, figs. 5, 6.
L 30- 32.5pm, W 30pm, I !Opm.
*S. sexcostatum Breb. ex Ralfs
PI. VII , fig . I.
L 40-45 pm , Wcpr 42.5-47.5 pP1 , I 17.5 pm.
*S. spongiosum Breb. ex Ralfs
PI. VIII , fig. I I.

Contribution to th e Des mid Flora of Papua New Guinea

17

Lcpr 47 .5- 52 .5 tJm , Wcpr 47.5- 55 fJm , I 12.5 fJm.

*S. teliferum Ralfs

PI. VIII , fig. 5

Lssp 42.5 tJm, Wssp 32 .5 fJm, Wcsp 42.5 fJm , I 15 fJm .
Bambusina Kiitz. ex Kutz.
B. borreri (Ralfs) Cleve
L 22.5- 27 .5 fJm , W 12.5- 17.5 ,um.

PI. VII , fig. 15

Hyalotheca Ehr. ex Ralfs
H. dissiliens (Smith) Breb. ex Ralfs
PI. VII, figs . 13, 14.
L 12.5- 15 ,um, W 20- 25 ,um.
The zygospores were seen in the majority of samples where this species was revealed.
Spondylosium Breb. ex Kutz.
S. planum (Wolle) W. et G. S. West
L 10- 12.5f.1m, W 12.5- l5f.1m, l5f.1m .

PI. VII , fig. 12.

Teilingia Bourr.
T. g ranulata (Roy et Biss.) Bourr.
L 10- 12.5f.1m, W 10- 12.5f.1m.

PI. VIII , fig. 14

References
Allorge, P. 193 0. La vegetat ion des lacs landais. Compt. Rend. Somm . Sea nces Soc. Biogeogr., 7: 44-46.
Cout e, A. & Tell, G. 198 1. Ultrastructure de la paro i cellulaire des Desmidi acees au microscope electroniqye a balayage. Beih . Nova Hedwigia, 68: 7- 228.
Croasdale, H. T. & Flint, E. A. 1988. Flora of New Zea land. Freshwa ter algae, Chl orophyta, Desmids. I!.
Univers ity Press, Botany Div., Christchurch, 147 p.
Croasdale, H. T. & Gronbl ad, R. 1964. Desmids of Labrador. I. Desmids of the south eastern coastal area.
u "Qns. American Microsc. Soc ., 83 : 142- 21 2.
Forster, K. 1964. Einige Desmidi acee n aus der Umgebung von Addi s Abeba . Rev. a/go!. , Paris, N. S. 7:
223- 236.
Forster. K. 1965. Beitrag zur ke nntni s der Des midi acee n-ft ora von Nepal. Khumbu Himal. Erg. Forsc h.Untern Ne pal Himalaya, I : 25- 58.
Hin ode, T. 1955. The desmid-ftora of Aka i- Yac hi ( I). J. Jap. Bot., 30: 1- 8.
Kanetsum a, Y. & Yamagishi , T. 1989a. Cosmarium pseudoco nnatum No rdstedt va r. subconstrictum Jao.
In: Yamag ishi, T. & Aki ya ma, M. (eds.), Photomi crographs of the fres hwater algae, 10: 13.
Kanetsuma. Y. & Yamagishi , T. 1989b. C. quadratu/um (Gay) De Toni va r. app/anum lnsam & Kri eg. In :Yamag ishi, T. & Ak iyama, M. (eds.), Photomi crog rap hs of the freshwater algae, 10: 15.
Kum ano, S. 1983. Studi es on fres hwater Rhodophyta of Papua New Guinea 11 . Batrachospermum
wo itapense sp. now. from the Papuan Highl and s. Jap . J. Phyco/., 31 : 76- 80.
Kum ano, S. & Watanabe. M. 1983. Two new va ri eti es of Batrachospermum (Rhodophyta ) from Mt. Albert Edwa rd, Papua New Guinea. Bull. Natn. Sci. Mus., Tokvo, Ser. B. 9: 85- 94.

18

A. A. Gontcharov, Masayuki Watanabe and Makoto M. Wata nabe

Lundell , P. M. 1871. De Desmidiaceis quae in Suecia inventae sunt, observationes criticae. Nova Acta

Reg. Soc. Sci . Upsa liensis, Ill , 8: 1- 100.
Neuha us , G . & Kiermayer, 0. 1982. Ra ster-e lektronenmikroskopi sc he Untersuchungen an Desmidiaceen : die Pore n und ihre Verteilungsmuster. Nova Hedwigia, 36, 499- 568.
No rdstedt, 0. 1873. Bidrag till kiinnedomen o m sydligare Nordes Desmidieer. Acta Univ. Lund. , 9: 1- 5 1.
Nordstedt , 0. 1880. De Al g is et C haracei s I. De algis nonnulli s, preacipue Desmidie is , inter UtriculariasMuse i Lugduno-Batavi. Acta Univ. Lund. , 16: 153- 164.
Prescott, G. W. , C roasdale, H. T. , Vinyard, W. C. & Bicudo, C. E. de M. 1981. A Synopsis of North
American Desmids. Parth 11. Desmidiaceae: Placodermae. Section 3. Un iv. Nebraska Press. Linkoln& London. 720 pp.
Ruz icka, J. , 1977. Di e Des midi aceen M itteleuropas. Band I, I. 29 1 pp. Li eferun g. E. Schweizerbart'sche
Ve rlagsbuchh andlung, Stuttgart.
Ruzi c ka , J. , 198 1. Die Desmidiaceen Mitteleuropas. Band I ,2. 293- 736 pp. Liefe rung . E. Schweizerbart 'sc he Ve rlagsbuchhandlung, Stuttgart.
Schulz, P. 1930. Zur Zygosporenbildung zwe ier Des midi aceen. Ber. Westpreuss. Bor.-Zool. Ver. , 52 :17- 23.
Skuja, H. 1949. Zur si.isswasse ralge n-flora Burmas. Nava Acta Reg. Soc. Sci. Upsa /iensis, Ser. IV, 14:

5- 187.
Thomasson, K. 1963. Araucanian Lakes. Acta Phy togeogr. Suecica., 47 : 1- 139.
Vyverman , W. 199 1. Desmids from Papua New Guinea. Bib/iotheca Phycol. , 87: 1- 200.
Watanabe, M. , Prescott, G. M. & Yamagi shi , T. 1979. Freshwater algae of Papua New Guinea (2).
Desmids from Woitape Central District. In: Kurokawa, S. (ed.), Studies on C ryptogam s of Papua
New G uinea, 1979, pp. 49- 66.
Watanabe, M. M. , Watanabe, M . & Yamagishi , T. 1979. Freshwater a lgae of Papua New Gu inea (3).
Blue-g reen algae from Mt. Wilhelm. In : Kurokawa, S. (ed.), Studies on Cryptogams of Papua New
Gu inea, 1979, pp. 67- 85.
William son, D. B. 1994. Observation on Desmids from Scotla nd, Shetland, Cumbria and the Engli sh
Midlands. Bot. J. Scotl. , 47: 11 3-122.
Williamson , D. B. 1996. A survey of the Desmid fl ora of Assynt , West Sutheland. Bot. J. Scotl. , 48:

235- 279.
Yamagishi , T. 1975. The Plankton Algae from Papua New Guinea. In : Otani, Y. (ed.), Reports on the
Cryptogams in Papua New Guinea, pp. 43- 74.
Yamagi shi , T. & Kanetsuma, Y. 1990. Freshwater Algae of Papua New G uinea (4). Some Eugleno id Flagellates and Desmids. Bull. Natn. Sci. Mus., To kyo , Ser. B, 16:4 1- 59.
Yamagi shi, T. & Watanabe, M. 1979. Freshwater a lgae of Papua New Guinea ( I). On some filamentous
green algae. In: Kurokawa, S. (ed.) , Studies on Cryptogams of Papua New Guinea, 1979, pp . 33-47.

Contributi on to the Desmid Flora of Papua New Guinea

19:..:~~
,,,
~ .,

'.

11
Plate I. I. Penium spirostriolatwn; 2. P. cylindrus; 3. Peniw11 sp.; 4. Closterium c/osterioides;
5- 6. Cl. navicula; 7. Cl. diana e; 8. Cl. jennerii; 9. Cl. tumidulum; I0. Cl. abruptum ; 11. Cl.
ralfsii var. gracilius; 12. Cl. striolatum ; 13. Tetmemorus laevis. Scale bar I, 4- 7,
9- 11 =40 ,Um , 2, 3 = 20,Um, 8, 13 = 30,Um, 1 2=60~1111 .

20

A. A. Gontcha rov, Ma sayuki Watanabe and Makoto M . Watanabe/

16

Plate 11. 1- 2. Actinotaenium cucurhita ; 3. A. ohcun eat11111 var. oravicum; 4. ?A . cruciferum; 5.
Euastrum obesum ; 6. E. sinuosum ; 7. E. insulare; 8. E. montanum; 9. Haplotaenium minimum ;10-12. Euastmm ansatum var. triporum : 13. E. denticulatum; 14. E. boldtii; 15. E. suba/pinum va r. crassum; 16, 17. E. gavanum; 18. Cosmarium pseudarctoum. Scale bar 1-4, 6- 8,
13- 18=20,um , 5, I0- 12 =3 0,um, 9 = 40,um .

Contr ibuti on to the Des111id Flora of Papua New G uin ea

I. Cosmarium connatum; 2. C. pseudoconnatum var. subconstrictum ; 3. C. pyramidatum; 4-5. ?C.javanicum ; 6- 7. C. tatricum ; 8- 9. C. tenue; 10. C. contractum va r. ellipsoideum ;11 . C. lapponicum. Scale bar I , 3, 6- 11 = 20 ,u m, 2 = 30 ,u 111, 4, 5=40 ,u 111.

Plate Ill.

21

A. A. Gontcharov, Masayuki Watanabe and Makoto M. Watanabe

22

7

13

c~

-~14
I. Cosmarium quadrawm ; 2-4. C. variolarum va r. skujae; 5. C. raciborskii; 6- 7. C.
pseudoniridulum; 8. C. nitidulum ; 9- 11. Cosmarium poroswn , sp. nov.; 12. C. laeve; 13. C.
sublateriundatum; 14. C. punctulatum; 15. C. minimum; 16. C. quadratulum var. applanum;
17- 18. C. crenarum. Sca le bar 1-4, 8- 18=20 )1111, 5-7 = 30 )1111 .

Plate IV

Contribution to the Des mid Flora of Papua New Guinea

Plate V 1- 2. Cosmarium sp.; 3-4. C. deCO!'alum; 5- 6. C. amoenum var. mediolaeve; 7- 8. C.
reniforme var. apertum; 9. C. caelatum . Scale bar 1-4=30 pm , 5- 9 = 20 pm.

23

24

A. A. Gontcharov, Masayuki Watanabe and Makoto M. Watanabe

1- 3. Cosmarium nasutum var. nasutum f. granular; 4, 5, 12 , 13 . C. guadrifilrium var.
octastichum; 6. Staurodesmus pachyrhynchus; 7. S. isrhmosus; 8. S. boergesenii; 9- 10.
Staurastrum dilaratum ; 11. S. inconspicuum; 14-16. S. conrectum var. aviceps; 17, 18. S. capitulum var. spimferum var. nov. Scale bar 1- 18 = 20 ,u m.

Plate VI.

Contribution to the Desmid Flora of Papua New Guinea

Plate VII. I. Staurastrum sexcostatum; 2. S . .fi~rcigerum; 3, 4. ?S . .forficu/arum; 5, 6. S. punctularum ; 7, 8. S. mmgaritaceum; 9. S. capitulum var. dimidio-minor ; 10, 11. S. muel/eri; 12.
Spondylosium planum; 13. 14. H ya/otheca dissiliens; 15. Bambusina bon·eri. Scale bar
l- 15 = 20,um.

25

26

A. A. Gontcharov, Masayuki Watanabe and Makoto M. Watanabe

0
I. Closterium moniliferum; 2. Euastrum binale; 3. Cosmarium pseudoconnatum ; 4. C.
tinctwn; 5. Staurastrum teliferum; 6. S. capitulum var. spiniferum , var. nov.; 7. S. capitulum
var. dimidio-minor; 8. Cosmarium sinostegos; 9. Staurodesmus omearii; 10. Cosmarium
obliquum; 11. Staurastrum ;pongiosum; 12. Cosmarium porosum sp. nov.; 13 . Staurastrum
muelleri; 14. Teilingia granulata. Scale bar I =60 ,urn, 2- 11 , 13 , 14 =20 ,urn, 12= 15 ,urn.

Plate VIII.

Contribution to the Des mid Flora of Papua New Guinea

Plate IX.

I. Euastrum ansatum va r. triporum; 2. ?Actinolaenium cruciferum ; 3, 4. Cosmarium sp.

27