Metamasius
Creators: name: Anderson, Robert S.
Publisher: name: Zenodo
Year: 2002
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Dryophthoridae
Metamasius

description: Key to species of Metamasius in Costa Rica and Panama (largely after Vaurie 1966, 1967a)
1 Outer apex of middle and hind tibia with distinct, minute tooth................................... 2
­ Outer apex of middle and hind tibia rounded or obtusely angulate, not dentate........... 3
2 Venter, except for abdominal ventrites, virtually impunctate; male rostrum with inner margin crenulate; inner margin of hind tibia of male with subapical tuft of long curled hairs.......................................................................... M. cincinnatus Champion (in part)
­ Venter distinctly punctate; male rostrum with inner margin smooth; hind tibia of male lacking hairs ......................................................................... M. rugipectus (Champion)
3 Elytral sutural interval and intervals 3, 5 and 7 elevated and wider than other intervals (fourth interval may be elevated at midlength); pronotum foveate on each side in front of base, also with lateral margins (viewed dorsally) somewhat emarginate from base to just beyond midlength ....................................... M. distortus (Gemminger and Harold)
­ Elytral intervals all of equal elevation and width; pronotum not foveate on each side in front of base, lateral margins (viewed dorsally) not emarginate ................................... 4
4 Pygidium from base to apex with high, bluntly keeled, tomentose swelling, in lateral view with apex distinctly truncate and angulate; inner margin of middle tibia of male sinuate and slightly expanded ................................................... M. pygydialis Guenther
­ Pygidium flat to slightly convex, midline may be setose and slightly elevated but not markedly so; in lateral view with apex rounded; inner margin of middle tibia of male straight to slightly sinuate, not expanded sinuate.......................................................... 5
5 Antennal club with apical pilose portion very short, visible in lateral view only at extreme apex of club as a narrow line; rostrum more or less straight, male with ventral margin irregularly crenulate ............................. M. wolfensohni Anderson, new species
­ Antennal club with apical pilose portion one­quarter or more length of entire club; rostrum straight or curved ventrally to various extent, male with ventral margin irregularly crenulate or smooth............................................................................................... 6
6 Hind tarsal article 3 only slightly expanded, width at apex less than twice width of article 2 at apex................................................................................................................... 7
­ Hind tarsal article 3 markedly expanded, width at apex more than twice width of article 2 at apex................................................................................................................... 8
7 Antenna with apical pilose portion one­third length of entire club; rostrum with fine,
yellow pilosity throughout most of length, divided dorsally by median glabrous line; tarsi densely tomentose dorsally ..................................................... M. cerasinus Vau r ie ­ Antenna with apical pilose portion about one­half length of entire club; rostrum with fine, yellow pilosity in basal one­third only; tarsi sparsely tomentose dorsally ............. ................................................................................................. M. hebetatus (Gyllenhal)
8 Prosternum in front of coxae with ring of distinct yellow hairs (usually as long as apical article of antennal funicle); antenna with apical pilose portion of club distinctly truncate and quadrate at apex ................................................. M. hemipterus (Linnaeus)
­ Prosternum in front of coxae glabrous or very finely pilose; antenna with apical pilose portion of club broadly rounded.................................................................................... 9
9 Prosternum in front of coxa with abrupt, tumid and punctate transverse swelling (swelling less pronounced on females and small males); male with large (huge in some specimens) ventrally produced, apically rounded tooth on the peduncle of postmentum; base of elytral interval 6 excavate and bidentate ....... M. maculiventris Champion
­ Prosternum flat to slightly convex in front of coxa; male with at most a small ventrally produced, rounded tooth on peduncle of postmentum; base of elytral interval 6 not modified…...................................................................................................................10
10 Elytra with basal one­half of all intervals filled with large, irregular, deep punctures; pronotumwithsimilar,largedeeppunctures;malerostrumwithventralmargincrenulate…. ............................................................................................ M. submaculatus Champion
­ Elytra with all intervals impunctate or at most very finely punctate; pronotum with punctures various; male rostrum with ventral margin crenulate or smooth ................ 11
11 Elytral striae each with numerous paired, large, micropilose pits................................... ........................................................................... M. leopardinus Anderson, new species
­ Elytral striae impunctate or with at most small linearly arranged fine punctures....... 12
12 Pronotal disc virtually impunctate (except for apical collar and extreme basal margin) ..................................................................................................................................... 13
­ Pronotal disc distinctly finely to coarsely punctate, punctures may be limited to subbasal median impressed area or may be fine and shallow throughout ........................ 19
13 Rostrum short and almost straight, length approximately 3­4 times width at apex; antennal club with apical pilose portion short, about one­quarter length of entire club…. ................................................................................ M. burcheri Anderson, new species
­ Rostrum slightly to moderately curved, length greater than 5 times width at apex; antennal club with apical pilose portion at least one­third or more length of entire club ..................................................................................................................................... 14
14 Pronotum with flanks and prosternum virtually impunctate; inner margin of hind tibia of male with tuft of dense, long golden hairs at middle.................................................. ................................................................................. M. cincinnatus Champion, (in part)
­ Pronotum with flanks and prosternum distinctly punctate; inner margin of hind tibia of male with or without tuft of long golden hairs............................................................ 15
15 Rostrum with large, distinct punctures immediately in front of point of antennal insertion; pronotal disc orange or red, with elongate black stripe along midline and shorter subbasal black spots on either side of midline .................. M. quadrilineatus Champion
­ Rostrum with at most fine, shallow, indistinct punctures immediately in front of point of antennal insertion; pronotal disc black, red with small black paramedian spots just anterior to midlength, or red with very broad black median area extended across basal margin..........................................................................................................................16
16 Pronotum red with small black paramedian spots just anterior to midlength, or red with very broad black median area extended across basal margin; male rostrum with ventral margin crenulate; male hind tibia with ventral margin with row or long, golden hairs in apical three­quarters ................................................. M. dimidiatipennis (Jekel)
­ Pronotum entirely black; male rostrum with ventral margin smooth; male hind tibia with ventral margin with row of uniformly short golden or brown peg­like hairs ..... 17
17 Body robust, length less than twice maximum width; metasternum tumid in lateral view; pronotum with basal margin virtually impunctate; elytra with series of small yellow dots near middle or a broad yellow band at middle with small black spot on interval 3.............................................................................................. M. sellatus Champion
­ Body more slender, length more than twice maximum width; metasternum flat medially; pronotum with basal margin with row of punctures; elytra with transverse yellow or orange band just anterior to, or posterior to, midlength.......................................... 18
18 Elytra with transverse yellow or orange band just posterior to midlength; male abdomen with last ventrite impressed; male hind tibia with inner margin with tuft of long golden brown hairs........................................................................ M. fasciatus (Olivier)
­ Elytra with transverse yellow or orange band just anterior to midlength; male abdomen with last ventrite flat; male hind tibia with inner margin with row of uniformly short brown hairs............................................................................... M. callizona (Chevrolat)
19 Pronotum with disc with distinct transverse subbasal impression or crease; Pronotum orange­red with single median black stripe of more or less same width throughout length; elytra with black "V­shaped" sutural maculation at middle (other various black markings also present); body size small, 6.0­ 6.9 mm ..................................................... ................................................................................ M. vaurieae Anderson, new species
­ Pronotal disc flat with slight to deep longitudinal or round subbasal impression; pronotum with color pattern various; elytra with color pattern various; body size small to large, 6.5­23.5 mm, most 8.0­12.0 mm ....................................................................... 20
20 Pronotal disc with punctures confined to subbasal median area (and subapically along apical collar)................................................................................................................ 21
­ Pronotum with disc with punctures (although fine and shallow in some specimens) more or less evenly scattered throughout.................................................................... 25
21 Pronotum with distinct subbasal median impression with large, deep punctures....... 22
­ Pronotum with subbasal median area flat or very slightly impressed, punctures moder­
ate to small and fine .................................................................................................... 23 22 Abdomen with last ventrite with large patch of long, dense, golden brown hairs in apical one­half; all tibiae of male with inner margins with dense, long, golden brown hairs; body size large, 21.0­ 23.5 mm ............................... M. sierrakowskyi (Gyllenhal)
­ Abdomen with last ventrite glabrous (female) or with two small paramedian patches of long golden hairs at about midlength (male); front and middle tibiae of male with inner margins with sparse, elongate golden hairs, hind tibia with inner margin with tuft of long golden hairs at about midlength; body size moderate, 9.5­13.0 mm ...................... ....................................................................................................... M. difficilis Guenther
23 Rostrum in lateral view more or less of same width throughout length; antennal club about as wide as long; male rostrum with distinct, paired, ventral swellings under apical margin of scrobe ......................................... M. shchepaneki Anderson, new species
­ Rostrum in lateral view more distinctly tapered in apical one­half; antennal club much longer than wide; male rostrum with ventral margin smooth ..................................... 24
24 Front coxae separated by about one­half the width of a coxa; male (female not known) hind tibia with inner margin with distinct tuft of dense, long, golden hairs at midlength…. ................................................................................ M. bellorum Anderson, new species
­ Front coxae separated by no more than about one­third the width of a coxa; male hind tibia with inner margin with row of sparse, long, golden hairs in apical two­thirds....... .......................................................................................... M. bromeliadicola Champion
25 Rostrum of male (female not known) ventrally near base with tuft of dense, coarse, yellow hairs; antennal club with apical pilose portion about one­quarter length of entire club ........................................................................................... M. crinitus Vau r ie
­ Rostrum glabrous ventrally; antennal club with apical pilose portion about one­third or more length of entire club ........................................................................................... 26
26 Pronotal disc with punctures large, dense and deep, many contiguous or nearly so; rostrum of male with ventral margin crenulate; pygidium with pair of paramedian apical tufts of long golden hairs....................................................... M. octonotatus Champion
­ Pronotal disc with punctures fine, sparse and shallow to moderately dense and moderately deep, punctures widely separated, not contiguous or nearly so; rostrum of male with ventral margin smooth or with slight ventral swelling at about midlength; pygidium various.................................................................................................................. 27
27 Pronotum widest at base, tapered uniformly throughout length to apex, elongate­narrow in general form; male hind tibia with inner margin with row of dense, long, dark hairs in apical two­thirds…. .............................................................. M. alveolus Vau r ie
­ Pronotum widest anterior to base or of more or less equal width from base to near apex, abruptly constricted and tapered subapically, subquadrate in general form; male hind tibia with inner margin with row of uniformly short hairs or with row of sparse, long, fine yellow hairs in apical two­thirds................................................................. 28
28 Rostrum in lateral view robust in form, length about 4 to 5 times width at apex, about
as wide at apex as at base, or at most only very slightly narrower at apex................. 29 ­ Rostrum in lateral view elongate and slender in form, length much more than 5 times width at apex, distinctly narrower at apex than at base............................................... 31
29 Inner margin of front tibia with rows of dense, long golden hairs; rostrum with ventral margin crenulate…. ............................................ M. dasyurus Champion, male (in part)
­ Inner margin of front tibia with row of uniformly short hairs; rostrum with ventral margin smooth............................................................................................................. 30
30 Elytral interval 5 with pair of tumid elongate orange/red spots or a longer continuous tumid line, spots or lines slightly distorting adjacent elytral striae; male abdomen with last ventrite (5) with large patch of golden hairs in apical two­thirds; female abdominal ventrites 3­5 with elongate, fine, appressed, golden hairs along midline ....................... .................................................................................. M. hooveri Anderson, new species
­ Elytral interval 5 various in color, not tumid, adjacent elytral striae not distorted, straight; male abdomen with last ventrite (5) with large patch of golden hairs in apical two­thirds; female abdominal ventrites 3­5 glabrous............. M. sulcirostris Champion
31 Rostrum more or less straight, anteriorly directed; body size small, 6.0 mm................. ..................................................................................................... M. scutiger Champion
­ Rostrum at least somewhat curved ventrally; body size, small to moderate, 7.5­14.3 mm ..................................................................................................................................... 32
32 Elytra with only transverse orange or red band at basal one­third; body size small, 7.5­ 9.3 mm ….................................................................. M. murdiei Anderson, new species
­ Elytra with pattern various, if band present, it is at midlength and other parts of elytra with at least some red or orange as well; body size small to moderate, 8.2­14.3 mm ... ..................................................................................................................................... 33
33 Pronotum and elytra flat in lateral view; pronotum uniformly distinctly punctate over entire surface of disc; elytral intervals with distinct fine punctures; pygidium of female with midline with patch of dense, elongate hairs in apical one­half, no apical tufts present ................................................................................. M. atwoodi Anderson, new species
­ Pronotum and elytra at least slightly convex in lateral view; pronotum with punctures various in depth and density over disc; elytral intervals with fine punctures or impunctate; pygidium of female with pair of small paramedian apical tufts of hair or with large subapical tuft as well as pair of paramedian apical tufts.................................... 34
34 Elytra with slightly oblique red band at midlength and with intervals 3­6 red in area of subapical callus; ventral margin of rostrum of male with slight ventral swelling at about midlength; pygidium with pair of paramedian apical tufts; male hind tibia with inner margin with row of minute, peg­like brown spines ............................................... ........................................................................... M. richdeboeri Anderson, new species
­ Elytra with pattern various; ventral margin of rostrum of male either smooth or crenulate; pygidium various; hind tibia with inner margin various ..................................... 35
35 Tarsi with venter of article 3 with midline glabrous in a broad, triangular patch towards
base; pronotum with subbasal area with larger and deeper punctures than elsewhere on disc; areas lateral to punctate area virtually impunctate; male abdomen with last ventrite and inner margin of hind tibia with elongate, fine hairs .......................................... ................................................................................................ M. nudiventris Champion ­ Tarsi with venter of article 3 completely pilose, no glabrous spots evident; pronotum with subbasal area with punctures of more or less the same size and depth as elsewhere on disc, if punctures deeper and denser in impressed subbasal area, areas lateral to punctate area with at least some punctures; male abdomen with last ventrite glabrous and with inner margin of hind tibia with uniformly minute, peg­like brown spines...36
36 Pygidium with single, broad apical patch of short hairs; male front tibia with inner margin with row of uniformly short, peg­like brown spines; male rostrum with ventral margin smooth….................................................... M. gallettae Anderson, new species
­ Pygidium with large, preapical tuft of long hairs and small paramedian apical tufts (tufts may be contiguous medially); male front tibia with inner margin with rows of dense, long, fine golden hairs; male rostrum with ventral margin crenulate .................. ..................................................................................... M. dasyurus Champion, (in part)
description: Published as part of Anderson, Robert S., 2002, The Dryophthoridae of Costa Rica and Panama: Checklist with keys, new synonymy and descriptions of new species of Cactophagus, Mesocordylus, Metamasius and Rhodobaenus (Coleoptera; Curculionoidea), pp. 1-94 in Zootaxa 80 on pages 45-50, DOI: 10.5281/zenodo.156033