ak ney enemas ame sa Genes Thee Ty re, Fee te St i 1 a LOOLOGICA SCIENTIFIC CONTRIBUTIONS OF THE NEW YORK ZOOLOGICAL SOCIETY FROM THE TROPICAL RESEARCH STATION IN BRITISH GUIANA VOLUME III. NUMBER 6 (Tropical Research Station Contribution Number 100) DESCRIPTIONS OF NEW SPECIES OF COLEOPTERA By E. A. SCHWARZ and H. 8. BARBER United States Department of Agriculture 12 Uf 18) 1) IS} UBL 18) 1D) 18 YC WY IE 1} Sr OnG@r hii ¥ IEE 7 OOM OG NCA) SPAR K; NEW YORK DECEMBER 24, 1921 a a ane 7 ek ROPE ’ , Weed UOT Pane iit te par ian + | ne 3 ne tl eee yA an ria Volume III, Number 6 DESCRIPTIONS OF NEW SPECIES OF COLEOPTERA By E. A. SCHWARZ and H. S. BARBER United States Department of Agriculture Specimens of three species of beetles from Kartabo, Bartica District, British Guiana, have been submitted to us by their discoverer, Dr. W. M. Wheeler, for identification. Two of the species belong to the family Silvanide, while the third is an incon- spicuous species of the ubiquitous Coccinellid genus Scymnus. The two first are, however, very interesting forms, and it has been necessary to erect a new genus to receive the larger and more abundant species. These, Dr. Wheeler informs us, were occupying the petioles of a tree (Tachigalia). Coccidotrophus gen. nov. (Silvanide). ‘ q . Eyes small, not emarginate, not prominent, occupying middle fourth of side of head. Antenne inserted laterally, in deep cavity between frontal margin and prominent gena, close to and equidistant from base of mandible and front margin of eye; compactly eleven-jointed, club not abruptly enlarged, all joints traverse except basal joint; joints 3-9 rapidly increasing in size, the three-jointed club densely covered with fine short hairs. Antennal grooves short, distinct, parallel, bordered by lower edge of eye and carina from gena. Mouthparts free, maxil- lary palpi four-jointed, labial palpi three-jointed. Elytra with ateral costa and nine distinct series of strial punctures. *ygidium usually covered by elytra when abdomen is con- racted (when distended the pygidium is often exposed). itercoxal process of prosternum about one-seventh as ide as prothorax, wider behind, its sides overlapping the jimera; front coxae separated from hind margin of pro- thorax by about their own length. Intercoxal process of mesosternum slightly narrower than that of prosternum, truncate apically and nearly reaching hind margin of coxae, metepimeron reaching the middle coxae. Hind coxae separated by strong, 190 Zoologica: N. Y. Zoological Society [IIl;6 acute process of first abdominal sternite, which fits into median notch in metasternum. First ventral abdominal segment with coxal lines very fine, short, curved, becoming almost parallel behind, but not reaching posterior margin; four following sternites each slightly shorter than the first, the last rounded apically, concave beneath, with carinate posterior margin. Legs short, stout, femora incrassate, first three tarsal joints inflated, hairy beneath, fourth small but distinct, fifth joint as long as the three basal joints together. Genotype: Coccidotrophus socialis sp. nov. This genus is so unlike other Silvanids known to us that its true affinity was not recognized until Dr. Béving’s studies of its larva proved it to agree well with typical Silvanid larve and not to be related to Hapalips, with which we were trying to associate the adults. Once suggested this relationship was readily confirmed by the characters used by Ganglbauer (Die Kafer von Mitteleu- ropa, 1889, vol. 3, p. 577) to distinguish the adults of this family: front coxal cavities closed behind, metepimeron reaching middle coxae, etc. We cannot identify Coccidotrophus with any of the genera considered by Grouvelle (Ann. Soc. Ent. Fr., vol. 81, 1912, pp. 313-386), but it seems most nearly to approach Synoemis Pascoe (1866), the only species of which was described from the Malayan Peninsula. Coccidotrophus socialis sp. nov. (Plate VI, figs. 1 to 5). Very elongate, parallel, depressed, shining, castaneous, glabrous (except for sparse, microscropical, decumbent pubescence). Length, 3.5-4.5; width, 0.6-0.8 mm. Habitat—British Guiana. Head slightly wider than prothorax, widest at the very slightly prominent eyes, one-sixth longer than wide, feebly constricted into a neck in basal fourth, sides convergent in front, front margin broadly, shallowly notched; upper surface finely granulose except a small occipital smooth area, feebly convex, transversely somewhat tumid between and behind eyes, which 1921] Schwarz and Barber: New Coleoptera 191 are situated about middle of sides; clypeus not separated from front, produced into a strong marginal carina, surface convex medially, concave laterally, especially over antennal sockets; labrum very short, transverse, feebly chitinized, emarginate in front and with a row of about six stiff hairs; gular region strongly pilose, feebly concave; mandibles moderately prominent, strongly bidentate apically; antenne stout, shorter than width of front at their point of insertion. Pronotum three-fourths as wide as long, widest at apical angles which are subacute; narrow- est just before middle and at base; sides feebly sinuate, sub- parallel, front margin straight, hind angles obtuse, hind margin arcuate, surface longitudinally flat, transversely feebly convex, sparsely punctate, the punctures elongate, side margins with fine marginal line. Scutellum transverse, widest behind, finely punc- tate. Elytra slightly wider than pronotum, more than three times as long as wide, base emarginate, humeral angles subacute, sides subparallel to apical fourth, thence conjointly rounded; surface longitudinally somewhat convex, transversely rather strongly convex, strial punctures moderate, the interstices each with a series of slightly smaller punctures supporting fine, decumbent, short hairs. Under surface shining but with irregular microscopic sculpture between the sparsely scattered, nearly obsolete punctures which bear the short, fine decumbent hairs. Described from thirty-two examples from a large series collected by Dr. Wm. M. Wheeler at Kartabo in July and August, 1920. The sexes are almost indistinguishable unless the “‘palps” of the ovipositor are extruded. Characters of legs, antenne and mouth are shown in accom- panying figures. Type, allotype and paratypes.—Cat. No. 24070, U.S.N.M. Eunausibius Grouvelle, 1912. Although we have seen neither of the two species (Nawsi- bius tenebrionides and N. elongatus Grouv.) upon which Grou- velle, (Ann, Soc. Ent. Fr., vol. 81, 1912, p. 314) established this genus, his generic diagnosis applies so well to the species here described that his genus is adopted. The postcoxal lines are very feeble and difficult to see but are bent abruptly forward to the coxal cavity enclosing a small area under the trochanter: 192 Zoologica: N. Y. Zoological Society [III ;6 the antennal club seems to be more abrupt and larger, and the shape of the produced clypeus differs also from the figures Grou- velle, (Ann. Soc. Ent. Fr., vol. 65, 1896, p. 193) has given of the two previously known species. Eunausibius wheeleri sp. nov. (Plate VI, figs. 6 to 10). Elongate, parallel, moderately convex, smooth, shining, gla- brous, pale castaneous. Length, 3.0-3.5 mm.; width, 0.6-0.75 mm. Habitat.—British Guiana. Head wider than prothorax; eyes rather large and promi- nent, coarsely granulated, front widest in front of the rather strongly impressed fovea opposite which the margin is some- what thickened; front margin broadly, feebly emarginate, front angles obliquely truncate; surface finely granulate, feebly con- vex. Labrum membranous, concealed beneath front. Gular area feebly concave, opaque, finely pubescent, the lateral carinz bordering the antennal grooves convergent posteriorly and pass- ing middle of eye. Antenne as long as width of clypeus, club abruptly widened, oval. Pronotum about three-fourths as wide as long, widest at the slightly acute front angles, sides almost straight and parallel, finely carinate; front margin straight except small sinuation near angles, hind margin arcuate at mid- dle, on each side straight, hind angles obtuse. Surface trans- versely convex, longitudinally flat except for a pair of feeble impressions at basal fourth. Scutellum transversely oval, twice as wide as long. Elytra slightly wider than prothorax, three times as long as wide, sides parallel, apices evenly rounded; surface nearly smooth, strial punctures feebly impressed but conspicuous by coloration below surface. Callow specimens dis- play interstrial rows of microscopic appressed hairs. Under surface of body sparsely clothed with microscopic decumbent hairs, each set in a broad obsolescent puncture. Described from eighteen specimens submitted by Dr. Wheeler, to whom the species is dedicated. Two of the specimens, dissected and mounted on slides, are males. One _ speci- men, the allotype, is somewhat crushed and displays female sex 1921] Schwarz and Barber: New Coleoptera 193 organs. We are unable to distinguish the sex of the other fifteen paratypes. Type, allotype and paratypes——Cat. No. 24071, U.S. N. M. The antenne and legs are shown in accompanying figures. Scymnus Kugelann 1794 (Coccinellide) After some hesitation we have decided to offer the following description of what appears to be a new but very commonplace species of this genus, since we have failed to find any description applicable thereto. It will, perhaps, be long before the multitude of tropical species of Scymnus will be determinable. Scymnus (Diomus) xantholeucus sp. nov. Oval, very convex, shining, pubescent, pale yellow except basal two-thirds of elytra, meso- and metasternum and median third of first two abdominal segments, which are infuscate. Length, 1.7 mm.; width, 1.2 mm. Habitat.—British Guiana. Head and pronotum finely, rather densely punctate, elytra slightly more coarsely punctured; pubescence rather dense, the short, silky, suberect hairs bent in all directions forming no pat- tern. Scutellum pale. Elytra piceous in basal two-thirds, apic- ally flavescent, the pale area not sharply limited. Under surface moderately, densely and finely punctate, the pubescence decum- bent and regular. Prosternum with carinae convergent anterior- ly, reaching front margin and uniting in an arc; the enclosed area feebly concave and supporting moderately long hairs. Post- metacoxal line as in other species of Diomus (Group A of Horn 1895). Penultinate abdominal sternite very broadly and feebly emarginate in the male. Type (male), allotype and paratypes.—Cat. No. 24084, U.S.N.M. Described from two males and two females reared by Dr. Wheeler from larvae found among coccids in company with the two species of Silvanide. Although not related to semiruber Casey, the foregoing species is similar in shape and plan of coloration. A prescutellar infuscate area is suggested in one example. Fig. 1. Coccidotrophus socialis sp. PLATE VI. nov. Right side of head, with antenna and mouth parts, ventral view. X 58.5 Fig. 2. Fore leg of same. X 36.5. Fig. 8. Middle leg of same. X 36.5. Fig. 4. Hind leg of same. X 36.5. Fig. 5. Hind wing of same. X 36.5. Fig. 6. Eunausibius wheeleri sp. nov. Antenna. X 58.5. Fig. 7. Fore leg of same. X 36.5. X 36.5. Fig. 8. Middle leg of same. Fig. 9. Hind leg of same. Fig. 10. Hind wing of same. X 36.5. X 36.5. Th ert a QL Wheeler, William Morton. 591 Study of some social B74W48 beetles in British Guiana, Ent. 1921. ) = 9 D9) Pos St SOW i 1 !{\\| WT WA A || Wii | WL | ' NAAT 0 A AR NH ‘ i : , ‘