Leptomorphus titiwangsensis Borkent, 2012

Borkent, Christopher J. & Wheeler, Terry A., 2012, Systematics and Phylogeny of Leptomorphus Curtis (Diptera: Mycetophilidae) 3549, Zootaxa 3549, pp. 1-117 : 66-67

35. Leptomorphus titiwangsensis Borkent , new species

( Figures 38, 75, 122, 137, 150, 152)

DIAGNOSIS: The only extant species of Leptomorphus with the following combination of characters: laterotergite and anepisternum brown; wing with pale brown apical wing spot reaching to wing tip, pale medial wing spot absent; male genitalia with gonocoxite as long as tergite 9 with margins distinguishable, apex of gonostylus bifurcated, aedeagal apodemes present ( Fig. 122).

This species can be distinguished from most other Oriental and eastern Palaearctic species (including those in Papp & Ševčík 2011) based on the yellow katepisternum and metepisternum ( Fig. 38, both brown in all other species in these regions except L. babai , and L. ornatus ). It can be distinguished from L. babai by its yellow scutellum (brown in L. babai ) and from L. ornatus by its occurrence only in peninsular Malaysia and presumably different male genitalic morphology.

DESCRIPTION: Male. Head: yellow, somewhat dorsoventrally compressed in anterior view. Antenna 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 1–2 large bristles, few of setae on apicodorsal margin, none ventrally; flagellomere 1 with tapered base brown remainder brown; flagellomere 6 1.1X as long as broad. Clypeus ivory, dorsoventrally elongate oval; bristles on clypeus yellow, 6–8 strong bristles on ventral margin directed ventrally, remaining setae directed medioventrally, clypeus 2X as long as face. Face ivory; shape a subequal triangle, bare. Frons yellow; bare, frontal furrow running 3/4-full distance from dorsal margin towards ventral margin, frontal cleft running to lateral ocellus. Palpus yellow; segment 1 hidden behind eye, segments increasing in length, segment 5 ~1.5X length of segment 4, segment 3 spherical with apicolateral depressed patch of fine yellow setae partially encircled by strong dark setae. Labellum yellow. 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 1–1.5X diameter of laterals, lateral ocelli 3X their own diameter from eye margin, ocellar triangle dark brown/black with electric blue green specks. Thorax: Length 1.04 mm (0.90–1.23 mm, n = 3). Mostly dark brown with anterolateral area yellow. Scutum dark brown/black with blue-green specks, pair of small yellow anterolateral spots; surface of scutum bare; acrostichal setae absent; dorsocentral setae present as fine setae on posterior two thirds; two thirds row of lateral setae present; patch of setae on scutum at wing base present. Scutellum yellow; with 2–4 large bristles and few small bristles. Prescutum brown. Mediotergite dark brown with 2 bristles on posterolateral corners, absent. Laterotergite brown; anterior margin of laterotergite abutting katepisternum. Anepimeron brown. Anepisternum brown. Katepisternum yellow. Antepronotum and proepisternum yellow. Margin of anterior and posterior spiracles yellow with yellow trichia. Metepisternum yellow. 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; hind coxa with brown spot along length of anterior surface; hind femur with apex and basal 1/4 light brown; extreme anteroapical corner light brown on forefemur, on other femora dark brown; tarsi light brown. Midfemur without apical spinelike process. Tibia with covering of brown macrotrichia, foretibia without comb of short setae along length of anteroventral surface, tibial spurs light brown, foretibial spur length 2X apical thickness of foretibia, midtibia with faint, dorsal, bare patch of even thickness for 4/5 of its length, placed basally, shortest midtibial spur 0.6X length of longest, longest midtibial spur 5X apical thickness of midtibia, shortest hind tibial spur subequal to length of longest, longest hind tibial spur 4X apical thickness of hind tibia. Foreleg first tarsomere 1.8X length of foretibia. Wing ( Fig. 75): Length 4.5 mm (4.4–4.5 mm, n = 3). Hyaline; apical macula light brown, reaching wing tip, but fading towards posterior margin; medial macula absent. Macrotrichia in all cells. Setae on basal posterior margin of wing (along base of cell a) alternating long, short. Calypter with a few short setae. Vein sc-r present (sometimes very light), apical end joining R at 2X 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 fading before wing margin. M 4 -CuA fork arising just apically of origin of r-m. A 2 absent. Abdomen: Tergites 3–5 with anterior 1/3 yellow, remainder dark brown. Tergite 8 smaller than all other abdominal sclerites, with 4–5 bristles on each apicolateral corner. Genitalia ( Fig. 122): yellow. Sternite 9 reduced to thin rectangular sclerite attached to aedeagus. Tergite 9 longer than wide, rounded margins tapering into two short rounded lobes and medial indentation. Gonocoxite placed basally on T9, medial margins not reaching median line, a ventromedial lobe covering base of gonostylus, bearing gonostylus halfway to apex. Gonostylus a single lobe tapering towards middle and then bifurcated into two points and bearing several basal setae, gonocoxite III separate from gonostylus dorsomedially. Aedeagus 2/3 length of gonocoxite, tapering towards apex (slight central swelling), apodemes 1/4 total length. Parameres as a broad lobe with rounded apex and medial bump, apodemes 1.8X length of parameres and strongly bent dorsally at base.

Female adult. ( Fig. 38) As for male, except as follows. Thorax: Length 1.29 mm (1.27–1.31 mm, n = 2). Wing: Length 5.6 mm (5.4–5.7 mm, n = 2). Abdomen: Cercus yellow.

Immatures. Unknown.

BIOLOGY: Unknown.

DISTRIBUTION: Peninsular Malaysia ( Fig. 137), 1220–1280 masl.

DISCUSSION: This species was compared to the descriptions and figures of the recently described Oriental and Australasian species ( Papp & Ševčík 2011), and is clearly different from all of them and not a junior synonym.

ETYMOLOGY: This species is named for the Titiwangsa mountain range of peninsular Malaysia where the type specimens were collected .

MATERIAL EXAMINED: Holotype: here designated, adult male, pinned on double mount minute with genitalia in plastic vial on main pin, labelled “ Malay Penin [ MALAYSIA]:/ Pahang, F.M.S./ Fraser’s Hill / 4200’/ May 20 th 1932 / [underside of label] H.M. Pendlebury / F.M.S./ Museums.; HOLOTYPE ♂ / Leptomorphus / titiwangsensis Borkent / Det. C.J. Borkent 2012” [ BMNH]

Paratypes: labelled as for holotype except 29.i.1929 (1♂, 1♀); 29.v.1932 (1♀) ; viii.1926, B. Gater (1♂). All paratypes in BMNH .