Leptomorphus eberhardi Borkent, 2012

Borkent, Christopher J. & Wheeler, Terry A., 2012, Systematics and Phylogeny of Leptomorphus Curtis (Diptera: Mycetophilidae) 3549, Zootaxa 3549, pp. 1-117 : 28-30

11. Leptomorphus eberhardi Borkent , new species

( Figures 12, 13, 52, 100, 143, 150, 155)

DIAGNOSIS: The only extant species of Leptomorphus with the following combination of characters: scutum and scutellum evenly covered with fine trichia; male foretibia with a dense row (comb) of short anteroventral bristles; palp segment 5 with thick covering of fine, white, setulae; male genitalia with tergite 9 tridentate posteriorly (medial process laterally compressed), gonocoxite placed posteriorly on tergite 9, gonostylus small (~1/4 length of gonocoxite) with two short, round, apical projections ( Fig. 100).

This species is distinguished from most other Neotropical species missing R 4 by the yellow scutellum and striped abdomen ( Figs 12, 13). It can be distinguished from L. crassipilus as it is the only species with a large, laterally compressed posteromedial evagination of tergite 9 ( Fig. 100).

DESCRIPTION: Male. ( Fig. 12) Head: yellow, somewhat dorsoventrally compressed in anterior view. Antenna dark brown; scape yellow, with brown setae in single apical row extending from dorsum laterally into thick patch covering apicoventral process, basal third and entire medial surface bare, anterobasal patch of setulae present; pedicel yellow, with 1 large bristle, several setae on apicodorsal margin, patch of fine setae apicoventrally; flagellomere 1 with tapered base yellow remainder dark brown; flagellomere 6 1.6X as long as broad. Clypeus yellow, slightly laterally compressed oval; bristles on clypeus brown, 6 strong bristles on ventral margin directed ventrally, remaining setae directed medioventrally, clypeus 2X as long as face. Face light brown; shape a slightly wider than tall triangle. Frons light brown; bare, frontal furrow running 1/4 distance from dorsal margin towards ventral margin, frontal cleft more than 1X diameter of median ocellus anterior of median ocellus. Palpus with segments 1–4 yellow, segment 5 white; segment 1 small but visible below eye, segments increasing in length, segment 5 1.8X length and 0.8X width of segment 4 with even width from base to apex and covered in fine white setulae, segment 3 without definite patch of fine setae. Labellum light brown. Eye with very few, short inter-ommatidial setulae scattered on surface. Occiput yellow with appressed, anteriorly directed setae. Ocelli in a straight line, space between ocelli less than diameter of laterals, lateral ocelli 2X their own diameter from eye margin, ocellar triangle dark brown/black. Thorax: Length 1.48 mm (n = 1). Dark brown with yellow lateral spots. Scutum dark brown with blue-green specks; surface of scutum covered with trichia; acrostichal setae absent; single dorsocentral seta present anteriorly; two thirds row of lateral setae present; patch of setae on scutum at wing base small. Scutellum light yellow with covering of fine trichia; bristles absent. Prescutum yellow. Mediotergite dark brown with 4 bristles on posterolateral corners, and covering of appressed trichia. Laterotergite brown, with covering of appressed trichia; anterior margin of laterotergite abutting katepisternum. Anepimeron brown with posterodorsal corner yellow. Anepisternum dark brown. Katepisternum brown with dorsal third yellow. Antepronotum and proepisternum brown. Margin of anterior and posterior spiracles white with white trichia. Metepisternum white. Anapleural suture with anterior portion slightly curved dorsally. Halter with basal 1/3 of stem ivory, apical portion and knob dark brown. Legs: principally yellow; trochanters brown; midfemur with basal 1/3 dark brown, hind femur with basal 1/3 and apex dark brown; extreme anteroapical corner brown on forefemur, on other femora dark brown; tibia with apex brown; tarsi light brown. Midfemur without apical spine-like process. Tibia with covering of brown macrotrichia, foretibia with comb of short setae along length of anteroventral surface, tibial spurs light brown, foretibial spur length 2X apical thickness of foretibia, midtibia with strong, dorsal, bare patch of even thickness for 2/3 of its length, placed basally, shortest midtibial spur 0.78X length of longest, longest midtibial spur 5.1X apical thickness of midtibia, shortest hind tibial spur 0.83X length of longest, longest hind tibial spur 4.1X apical thickness of hind tibia. Foreleg first tarsomere 1.8–1.9X length of foretibia. Wing ( Fig. 52): Length 6.4 mm (n = 1). Hyaline; apical macula dark brown running from anterior to posterior wing margin, beginning halfway along R 5, but fading towards apex and posterior margin; medial macula extending from Sc to posterior wing margin (fainter on posterior third). Macrotrichia in all cells, though absent from posterobasal margin of cell a. Setae on basal posterior margin of wing (along base of cell a) alternating long, short. Calypter with group of macrotrichia. Vein sc-r present, apical end joining R within its own length prior to origin of Rs. R 4 absent. R 5 straight, slight posterior turn near tip. M 1 reaching apex before R 5, apices of M veins reaching wing margin. M 4 -CuA fork arising at same level as r-m. A 2 absent. Abdomen: Tergites principally brown, T3–6 with anterior 1/3 yellow. Sternite yellow. Tergite 8 smaller than all other abdominal sclerites, without bristles. Genitalia ( Fig. 100): basal half brown, remainder light yellow/white. Sternite 9 membranous. Tergite 9 slightly longer than wide, tridentate posteriorly with medial process laterally compressed. Gonocoxite placed apically on T9, medial margin not reaching medial line, bearing gonostylus 1/3 distance from base. Gonostylus small (~1/4 length of gonocoxite) with two short, round, apical bumps (located ventrally and dorsally, dorsal behind ventral in figure) and a single seta, gonocoxite III fused to dorsolateral margin. Aedeagus highly complex with what appear to be 4–6 short apodemes, lateral sclerotized component that is strongly sinusoidal when viewed laterally and tapering sharply in apical half. Parameres a simple taper laterally but apodeme strongly united with both gonocoxal apodeme and aedeagal apodemes/complex, with a basal hook-shaped spine pointing dorsally.

Female. As for male, except as follows. Generally darker in colour. Thorax: Length 1.48 mm (n = 1). Scutellum light brown. Wing: Length 6.5 mm (n = 1). Legs: Foretibia without comb of short setae on anteroventral surface. Abdomen: Tergites 3–5 with anterior 1/3 yellow, T6 with anterolateral yellow spots, remainder dark brown. Cercus yellow.

Immatures. Unknown.

BIOLOGY: Unknown, although this is likely the species used in a study of the web spinning behaviour of Leptomorphus larvae ( Eberhard 1990).

DISTRIBUTION: Costa Rica ( Fig. 143), 615–1325 masl.

ETYMOLOGY: This species is named after Dr. W.G. Eberhard in recognition of his contributions towards the understanding of the immature and adult behaviour of Leptomorphus , and his collection of the holotype.

MATERIAL EXAMINED: Holotype: here designated, adult male, pinned with genitalia in plastic vial on pin, labelled “ COSTA RICA: San Jose Region:/ San Antonio de Escazu : vii.1999./ el. 1325 masl. Malaise trap / W. Eberhard; HOLOTYPE ♂ / Leptomorphus eberhardi / Borkent, new species / Det. C.J. Borkent 2012” [ ZMUN].

Paratypes: COSTA RICA: La Suiza , x.1923, P. Schild (1♀, USNM) .