A N N A L E S HISTORICO-NATURALES MUSEI N A T I O N A L I S H U N G A R I C I Tomus 54. PARS ZOOLOGICA 1962.

New Species of Sobarocephala Czerny (Diptera: Clusiidae)

Ry A. Soós, Rudapest

The genus Sobarocephala C Z E R N Y is the richest in species in the family Clusiidae. About one-third of the species described up to now in the family belongs to this genus. This characteristically neotropic genus, as already stated twice by H E N N I G (6, p. 137; 7, p. 146), is overly ripe for revision. The latest comprehensive description of the species was published by M E L A N D E R and ARGO (11, p. 33—49) in 1924. This work could not but contain only 28 of the 48 species described today, therefore i t is partly obsolete, partly fails to submit reassuring identifications, since the authors included in the keys a number of species (11, p. 34 — 36) based only on descriptions, without having actually studied them. Un t i l some one succeeds to reexamine the types or at least the paratypes of all species, there is no hope of a complete and really most necessary revision. By the comparison of the descriptions as well as the experiences gained from the study of the available research material, i t seems that more than one species had been described several times and by different names, due of course to the considerable individual variability and the frequently substantial sexual dimorphism.

In my present paper, I submit some new species found in the unidentified materials of the Zoological Department of the Hungarian Natural History Museum, and especially of the United States National Museum, Washington. I should like to my gratitude to D R . C. W. SABHOSKY . my esteemed colleague and friend for his kind forwarding of the research material. Nor do I describe all species believed to be new but only those which, on the basis of the meagre comparative material and the often short and out-of-date diagnoses, I was sure to represent unknown taxa.

After H E N N I G (6, p. 135), i t is customary to distinguish two groups, namely species wi th black, and densely bushy-plumose aristae, and those but sparsely and loosely plumose. To what degree this subdivision of the species also implies the segregation of two natural and allied groups cannot as yet be established, but one thing is sure, namely that the detachment on this ground of the species into two assemblages in easy and unambiguous. The majority of the species belongs to the one featuring a loosely plumose arista, and I could find wi th respect to only eleven taxa that they excel with a black, densely plumose arista.

I . SPECIES W I T H DENSELY, BUSHY PLUMOSE ARISTAE

Sobarocephala nigrofacies sp. nov.

? — General color dir ty yellowish. Occiput, postgenae and facialia d i r ty yellow, frons, cheeks brownish yellow of a greenish shade; antennae, except dark spot around base of arista, reddish yellow; mouthparts yellowish brown, face, prelabrum and ocellar spot black. A blackish transversal stripe of indistinct margins extending between two inclinate fronto-orbitals on anterior t h i rd of frons. A l l cephalic bristles brownish yellow. Notum ornamented w i t h extensive black pattern (Fig. 1 : R) ; l ight basic color medially behind transverse suture somewhat reddish brown in zone between two row of dorsocentral bristles,

humeral callus dir ty yellow, area between humeral callus and median black stripe in front of transverse suture as well as oblong spot on each side immediately behind transverse suture brownish yellow. Scutellum, metanotum (=medio-tergite), pleurotergites black; first two shiny, last one whitish pruinose. Pleurae glistening, shining black, except dir ty yellowish propleurae. A l l thoracic bristles brownish yellow. Coxae of middle and hind legs and all femora brownish yellow r, fore coxae and tarsal joints of middle and hind legs light yellow, all tibiae and tarsal joints of fore legs black. Hyaline wing covered wi th extensive, irregularly shaped brown spot of different intensity (Fig. 1 : C). Haltères l ight yellow. Abdomen dark castaneous brow rn, but tergites 1 and 6 yellow, except longitudinal dark stripe in middle; tergite 2 wi th a large, triangular yellow spot on each side; sternites 1, 2 and 6 also yellow; posterior portion of tergites 2—4 bordered wi th black cross-stripe about one-fourth as wide as length of tergite. Hypopygium yellow. Except light areas, abdominal bristles and hairs dark brown to black.

Fig. 1. Sobarocephala nigrofacies sp. nov. A = head laterally; B = thorax viewed from above; G = wing

Head (Fig. 1 : A) about one-third higher than long and about one-third wider than high. Frons tapering posteriorly, as long as wid th of its anterior margin; at narrowest section one-fifth as wide as its whole length. W i d t h of frons, measured at its middle, about two-fifths of width of head; and, measured at same point, frons but slightly wider than diameter of eye. Frons impressed like saddle. Face protuberant as in some other species of genus. Cheeks about one-fifth as high as eye, postgenae conspicuously broadening posteriorly; eye elongated oval. Postvertical bristles weakly developed, th in , comparatively short, ocellar bristles absent, that is, represented in their places by very short, stunted hairlet, hardly discernible by 100 magnification. External vertical bristles (vie) well developed, hardly shorter than inner verticals (vti). Of 11—15 occipitals, upper 5 — 7 inclinate, others reclinate. Anterior inclinate fronto-orbital bristle stronger and longer than two pairs of reclinate equally strong posterior ones. Distance between posterior fronto-orbitals twice as great as that between inclinate and anterior reclinate ones. Vibrissae well develo-ped, yet not long (half length of arista), slightly inclinate but more erect,

with 4—4 buccal hairs behind them. Second antennái joint with a long, straight terminal, dorsal bristle. Third antennái joint slightly oval, somewhat longer than wide, hairs of densely, bushy-plumose arista about 2 — 2,5 times longer than its basal diameter.

Notum covered with uniformly distributed, dense, short, light pilosity. Two pairs of dorsocentrals behind transverse suture, posterior pair twice as long as anterior one. Well developed prescutellars as long as anterior dorso-centrals. Pleurae completely smooth, w rith but one long meso- and sternopleural hair each. Two well developed, slightly arched and almost parallel apical or rather subapical bristles on bulging, glabrous scutellum; these about three times as long as two preapicals, that is, laterals (Fig. 1 : B). Dorsal preapical bristle of middle tibiae well developed. Wing not quite twro and a half times as long as broad. Ratio of penultimate and ultimate section of vein m as 1 :3,7. Distance between twro crossveins almost twice as long as length of posterior crossvein. Marginal bristles of abdomen not conspicuously long.

D i m e n s i o n s : total length: 4,2 mm; length of thorax; 1,6 mm; length of wing: 3,5 mm.

D i s t r i b u t i o n : Rrasil: Tinguá, Rio de Janeiro R. C. SHANNON coll. (holotype £ ).

L o c a t i o n of t y p e : U. S. National Museum, Washington. By reason of its shining, black pleurae, i t stands closest to the species

S. zeugma H E N N . , but it differs conspicuously from it — or indeed from any other congeners belonging to this group — by its black face and prelabrum. Furthermore, it deviates from the above species also essentially by the well developed prescutellarbristles,wholly different thoracic pattern, and coloration of the legs.

Sobarocephala pruinosa sp. nov.

er71 — General color yellow. Head variously shaded yellow, but ocellar spot and densely plumose arista black. Upper half of occiput, posterior two-third of frons brownish yellow; face, antenna (except dark, irregularly shaped spot around base of arista), and anterior third of frons light yellow; frons partly golden pruinose, antenna hoarily dusty, face with a shiny, light brown stripe extending from base of antennae to peristome. Cheeks, postgenae and lower half of occiput wdiitish grey; upper two-third of cheeks and postgenae (except posterior margins) whitish pruinose, this bloom extending along eyes to light brown stripe of face, reaching base of antenna : thus white pruinosity bordering lower margin of eye in a semicircle. Mouthparts and palpi very pale yellow, indeed, formers almost white. Al l bristles of head brownish yellow. Notum, pleurae and scutellum almost wiiolly light yellowr, with but a larger black spot on each side in front of alar base, and a brown stripe each decurrent from posterior dorsocentral along two sides and to middle of scutellum; metanotum ( = medio-tergite) brown, pleurotergites whitish pruinose; metapleural callus and along border of pteropleura browrnish. Thoracic bristles brownish yellow. Legs very pale yellow, only tarsal joints of fore legs blackish, and greater portion of coxae almost whitish. Subhyaline wing light greyish white pruinose, with a darker, indistinct brownish spot anteriorly of apical fourth. Haltères light yellow, partly yellowish white. Abdominal tergites brown, greyish pruinose, sternites light yellow. A broader longitudinal stripe each laterally on tergites 1 and 2, a spot each laterally on anterior margins of tergites 3 — 5, and first fused post-abdominal tergite dirty yellow; surstyli and adjacent area light yellow. 25 Természettudományi Múzeum Évkönyve - 22

Head (Fig. 2 : A) only about one-fifth higher than long, and about one-third wider than high. Frons narrowing posteriorly, one-fourth longer than its wid th measured, at anterior margin, and hardly more than its half length wider than long, measured at its narrowest point. Frons, measured at middle, one-third wid th of head: eye, measured at same point, scarcely wider than frons. Frons slightly concave, face protuberant in middle. Cheeks about one-fifth height of eyes. Postgenae not noticeably broadening posteriorly. Eyes obliquely elliptical.

Fig. 2. Sobarocephala pruinosa sp. nov. A = head laterally; B = surstylus viewed posteriorly; C = hypopygium

Postvertical bristles well developed, th in , ocellar bristles absent. External vertical bristles well developed, only one-fifth shorter than inner verticals. 11 — 14 occipitals strong, thick (similar to stiff setae of many Trypetids); upper 7—8 shorter and inclinate, lower 5 — 6 longer, straight, proclinate and slightly erect. A l l three pairs of fronto-orbital bristles of approximately same length; distance between two reclinate fronto-orbitals two and a half times greater than that between anterior inclinate and anterior reclinate ones. Vibrissae well developed, two-third of length of arista, strongly erect and but slightly inclinate, followed behind by 5 —5 very th in but comparatively long buccal hairs. Second antennái joint w i t h a long, rigid dorsal, terminal hair. Third an tennái joint oval to quadrangular, hairs of densely plumose arista about twice as long as its diameter at base.

Notum covered w i t h very th in , comparatively long, procumbent hairs. Two pairs of dorsocentrals behind suture, anterior one shorter, about three-fifth of length of posterior one. Prescutellar bristles absent. Pleurae completely glabrous, shiny. Well developed, slightly arched and somewhat converging two subapical bristles of scutellum only twice as long as two pairs of almost equally long lateral bristles. Dorsal preapical bristle of middle legs well developed. Strong but short bristles in antero- and postero-ventral rows only on apica. th i rd of fore femora ; middle femora w i t h no other but complete postero-ventral row of bristles; these more sparsely spaced, longer, but not as strong as on fore femora. Wing three times as long as wide. Ratio of penultimate and ultimate sections of vein m as 1 : 4. Distance between two crossveins about one and a half times greater than length of posterior crossvein. Surstyli (Fig. 2 : C) of an elongated isosceles triangle, slightly convex, exterior surfaces covered w i t h long hairs, on apical ends wi th about 10 black, strong, short and blunt spines on inner side (Fig. 2 : B) .

£ — Generally conforming w i t h male, yet differing in following characters : On notum, stripe (extending backwards from posterior dorsocentral to side of scutellum) emitting also anteriorad a much narrower streak, along dorsocentral

bristles, to transverse suture. Tarsal joints of fore legs more intensely blackish. Notum and scutellum lemon, that is, sulphur, yellow. A small, indistinct brown spot also in posterior crossvein area on wing; veins dark brown. A specimen designated as paratype (unfortunately lacking major part of abdomen) slightly deviating from other paratype insofar as very narrow brown stripe extending anteriorly on notum broken, wings not pruinose; but coxae and basal third of femora with strong, white pruinosity.

D i m e n s i o n s : total length: c/1 4,7 mm, £ 5,0 mm; length of thorax: c? ? 1,7 — 1,8 mm; length of wing:

middle) one-third wid th of head, and, measured at same point, eyes hardly wider than frons. Frons concave, face slightly protuberant in middle. Wid th of cheeks one-fifth to one-sixth height of eye. Eye oval. Postvertical bristles well developed, th in , yet comparatively long, ocellar bristles absent, that is, a very stunted haiiiet visible at their place (100 magnification). External verticals well developed, probably not much longer than inner ones, but exact ratio impossible to establish owing to broken off apices. Of occipital hairs, 6 upper ones ascending, shorter and thinner than posterior, or more correctly lower,

Fig. 3. Sobarocephala columbiensis sp. nov. A = head laterally; B = abdomen from above; C = wing; D = hypopygium

7—8 stronger, straight and reclinate ones. A l l three pairs of fronto-orbitals about approximate i n length, distance between two reclinate ones twice as great as that between inclinate and first reclinate ones. Vibrissae strong but comparatively short, about half as long as arista, erect and but slightly inclinate. 4 buccal hairs behind them, first (immediately following vibrissa) very well developed, strong, bristle-like, almost as long as vibrissae; other three short, th in , at first glance as if possessing 2 — 2 strong vibrissae. Third antennái joint subdiscoidal. Arista densely, compactly, bushy, hairs about twice as long as its diameter at base.

Notum uniformly covered wi th short, fine, l ight hairs. Pleurae almost entirely glabrous, except sternopleurae clothed w i t h sparse, erect hairs. First pair of two dorsocentrals hardly more than half its length longer than posterior one: prescutellars weakly developed, but well discernible. Two prothoracic bristles vestigial, but meso- and sternopleural bristles strong, long. Of three pairs of scutellar bristles, subapical one strong, slightly curved and somewhat convergent, preapical and lateral pairs short, about one-fifth of apicals. Dorsal preapical of middle tibiae very strong and long. Antero- and postero-ventral rows of bristles of fore femora consisting of short and thin hairs, rows of middle femora barely discernible. Wing about three times as long as broad. Ratio of penultimate and ultimate sections of vein m as 1 : 4 . Distance between two crossveins one-third longer than length of posterior crossvein. Marginal hairs of abdomen strong, almost twice as long as hairs covering segments. Surstyli (Fig. 3 : D) very characteristical, of a fungoid shape.

D i m e n s i o n s : total length: 3 ,5 m m ; length of thorax: 1,2 m m ; length of wing: 2,9 mm.

D i s t r i b u t i o n : Comlubia : Aracataca, I I . 1912, leg. Ú J H E L Y I (holo-type or").

L o c a t i o n o f t y p e : Zoological Department of the Hungarian Natural History Museum, Budapest.

Aside of its light-spotted black scutellum, the species has a very charac-teristical abdominal pattern, and unicolorous yellow pleurae and legs, which together w i t h only the small black spots each in front of the wings on its meso-notum, make i t easily distinguishable from all other congeners belonging to this group.

I I . SPECIES W I T H LOOSELY PLUMOSE ARISTAE

Sobarocephala nigroantennata sp. nov.

? — General color light brownish yellow. Upper half of occiput, first th i rd of frons, a short stripe (extending from between antennái bases on anterior margin of frons to median line of face), mouthparts, palpi, very narrow lower margin of cheeks, and basal (1.) joint of antennae light yellow. Lower half of occiput, face (except stripe as described above), cheeks, postgenae light greyish white ; face mat hoary; major part of cheeks and postgenae silvery pruinose of a silky shine. Posterior two-third of frons greenish yellow. Second and th i rd antennái joints and arista velvety black, ocellar spot partly blackish. Thorax light brow-nish yellow, mesonotum slightly darker than pleurae; humeral calluses, prople-urae and prosternum light yellowish white. Scutellum light yellow w i t h a slight greenish shade. Metanotum shiny, glistening, light yellowish brown. Legs yellow, but tarsal joints 2—5 of all legs dark brownish. Wing subhyaline, w i t h a light brownish hue, but costal margin and apical third a much darker brown. Haltères yellow7. Abdomen a shining brownish yellow, traces of a dark longi-tudinal stripe discernible in middle of first tergite. Bristles of head and thorax brownish yellow, abdominal ones black.

Head (Fig. 4 : A) about one half higher than long, and one-fourth wider than high. Impressed, saddle-shaped frons slightly narrowing posteriorly, only a bit longer than wide as measured on anterior margin. Frons, measured at middle, somewhat wider than one-third wid th of head, and (measured at same point) but one-fourth wider than eye. A canaliform depression extending from between an tenná i bases in middle of face, reaching epistome, broadening gradu-ally to an infundibuliform shape. Lower margin of cheeks obliquely decurrent posteriorad, its w id th (measured in middle) but one-fifth to one-seventh height of eye. Eyes obliquely oval. Postvertical bristles well developed, strong, ocellars weak, hair-like, only about one-third as long as postverticals. External verticals weak, about as long as postverticals, inner ones well developed, strong, two and a half times longer than externals. Upper part of about 14 — 15 occipital hairs proclinate, th in , lower part reclinate, straight, strong; uppermost ones longest. Three pairs of fronto-orbital bristles subequal, distance between two reclinate ones more than three times greater than that between inclinate and first recli-nate ones. Vibrissae strong, strongly inclinate and but slightly erect. Behind vibrisse, 5 — 6 t h in , subequal buccal hairs. Third an tennái joint subquadrangular, aristal base in its slight impression. Arista loosely haired, hairs two to three times longer than diameter of base.

Notum evenly covered wi th very t h in and short, light hairs. Three pairs of dorsocentrals, first one very weak, other two well developed, their ratios being 1 : 2 : 3 ; prescutellar bristle discernible but weak, hardly attaining length of first dorsocentral. Pleurae entirely glabrous, bearing only a single, vestigial prothoracic and one strong meso- and sternopleural bristle each; some th in , longer hairs also along posterior margin of mesopleura (below mesopleural bristle). Of three pairs of scutellar bristles, subapical one strong, slightly arched and divergent, preapicals and laterals also well developed, not quite half as long as subapicals. Three strong, curved bristles each on lower portion of fore and middle coxae. Comparatively well developed antero- and postero-ventral rows of sparsely spaced and thin bristles extending on fore femora, w i t h two

Fig. 4. A = Sobarocephala nigroantennata sp. nov., head laterally. — B —C = = Sobarocephala annulata albiventris subsp. nov. B = hypopygium; C = head

laterally

stronger bristles in apical th i rd dorsally. Dorsal preapical bristle of middle legs relatively strong. Wing almost three times as long as wide, ratio of penultimate and ultimate sections of vein m as 1 : 3 ,5 . Distance between two crossveins one-third longer than length of posterior cross vein. Comparatively sparsely spaced marginal hairs of abdomen well developed.

D i m e n s i o n s : total length: 3 ,7 — 5,0 m m ; length of thorax: 1,4 — 2,3 m m ; length of wing: 2 ,9—4,3 mm.

D i s t r i b u t i o n : Brasil: Rio de Janeiro, Dist. Federal, Sept. 1938, Servico Febre Amarela (holotype ? ) , Panama Ft . , Gulck, 16 Oct. 1953, F. S. R L A N T O N leg. (paratype ? ).

L o c a t i o n o f t y p e s : Holotype in U . S. National Museum, Washington; paratype in Zoological Department of the Hungarian Natural History Museum, Rudapest.

I should like to note tath the paratype specimen deviates in some of its features from the holotype, but since there are only two specimens available, the differences cannot be valuated taxonomically. The most striking difference is in the size of the two animals, as is to be seen from the dimensions given above. Furthermore, the external vertical bristles on the paratype are well developed and hardly shorter than the inner ones, the ocellar and postvertical bristles are

almost equally long, and there is no trace of a dark longitudinal stripe on the first abdominal segment, — to mention but the most salient differences.

The velvety black antennae of the newr taxon distinguishes it immediately and conspicuously from all known species. It is also specifically characterized by the wholly unicolorous, yellow thorax and legs, with only tarsal joints 2—5 being dark.

Sobarocephala a n n u l â t n albiventris subsp. nov.

a71 — Partly blackish brown to black, partly yellow or white. Upper part of occiput yellowr, lower portion slightly yellowish white, frons brownish yellow, anteriorly lighter; ocellar spot black. In middle of frons, an indistinctly delimited brown stripe extending from ocellar spot to almost its anterior margin; a longi-tudinal spot each along margin of eyes, from upper reclinate fronto-orbital to external vertical bristle. Face, cheeks and postgenae light fumose grey, but margin of whole epistome deep black ; a large, triangular black spot resting with its base on epistome in middle of face. Lower black margin on cheeks and postgenae gradually lightening into smoky grey basic color; no trace of a silvery dust of a silky shine on face and cheeks. Mouthparts pale yellow, palpi brownish yellow. Antenna! joints 1 and 3 yellowish white, 2 brownish yellow, 1 and 3 whitish in ventral view. Arista dark browrn.

Notum light yellow, shiny, humeral calluses whitish yellow. On middle of notum, a broad, shining, longitudinal black stripe, extending from before transverse suture. A wider black cross-stripe in front of, and a narrow one behind, base of wings. Former not connected with median longitudinal stripe, extending over mesopleura and terminating on upper end of sternopleura ; latter one short, connected with median longitudinal stripe, spreading over pleurotergites. Except cross-stripes, pleurae snow-wiiite. Scutellum black, metanotum black, with a large yellow spot medially. Coxae and bases of femora snow-white. Legs light yellow, but broad ring (filling middle third) of all femora, fore tibiae (except apical ends), and basal half of middle and hind tibiae dark brown. Wing slightly fumose (light brownish), apically somewhat darker, with a large, dark brown spot at termination of vein r 2 + 3 . Haltères snow-white. Abdo-men dark brow-nish black, tergite 1 and anterior margin of tergite 2 as well as sternites 1 and 2 also snow-wrhite. All bristles and hairs black.

Head (Fig. 4 : B) more than half its length higher, and one-third wider than high. Frons with almost parallel margins, hardly narrowing posteriorad; frons as wide as long, wider than one-third width of head, and almost one-third wider than eyes. Frons also concave, upper part of face slightly protuberant in middle, lower part (black triangular spot) depressed. Cheeks comparatively broad, one-sixth to one-seventh height of eye; postgenae very short. Palpi covered with short but strong spines. Postvertical and ocellar bristles well developed, former ones slightly longer, latter ones proclinate and parallel. External verticals comparatively well developed, (inner verticals unfortunately broken away, thus length and ratios to former ones impossible to establish). Of occipital hairs, upper 5 — 6 thin, ascending; upper part of 9 — 10 bristles ranging below considerably longer than lower 5. Of 3 pairs of fronto-orbital bristles, inclinate ones longer than reclinate ones. Vibrissae broken off, but 5 thin, yet relatively long buccal hairs originating behind them. Third antennái joint discoid. Arista covered with sparsely spaced long hairs, 2,5 — 3 times longer than its basal diameter.

Mesonotum covered w i t h fine, short, procumbent hairs. Two pairs of post-sutural, wel l developed dorsocentral bristles, w i th another stunted pair discer-nible in front. Unfortunately, majority of thoracic and scutellar bristles broken off, ratios thus unknown. Prescutellars very th in , comparatively long, — yet black, hair-like, thin bristles hardly recognizable against black base. Pleurae glabrous, except sparsely hairy meso- and sternopleurae. Twro vestigial protho-racic, and a strong, long, meso- and sternopleural bristle each. Of three pairs of scutellar bristles, only left lateral present, others discernible only by their points of emergence. On lower portion of fore coxae 3, and on middle ones 2, strong, curved bristles. Antero- and postero-ventral rows of bristles of fore femora consisting of sparsely spaced but long bristles. Dorsal preapical bristle of middle tibiae well developed. Wing two and a half times longer than wide. Ratio of penultimate and ultimate sections of vein m as 1 : 2,3. Distance between two crossveins twice as great as length of posterior crossvein. Marginal bristles of abdomen sparsely spaced, strong, long. First tergite almost glabrous, wi th but one group of hairs each laterally on posterior portion. Surstyli (Fig. 4 : B) thin, apically proclinate at right angles, sharply distinct from ninth (?) tergite.

D i m e n s i o n s : total length 3,8 m m ; length of thorax: 1,6 m m ; length of wing: 3,5 mm.

D i s t r i b u t i o n : Ecuador: Guayas Chilcales. 1. Aug. 1955. leg. L E V I C A S T I L I O (holotype