Bittacomorphella nipponensis Alexander 1924

Fasbender, Andrew & Courtney, Gregory W., 2017, A revision of Bittacomorphinae with a review of the monophyly of extant subfamilies of Ptychopteridae (Diptera), Zootaxa 4309 (1), pp. 1-69 : 53-55

Bittacomorphella nipponensis Alexander 1924

Bittacomorphella nipponensis Alexander 1924: 51 –52 (catalog)

Bittacomorphella nipponensis Alexander, Alexander 1927: 9 (catalog)

Bittacomorphella nipponensis Alexander, Peus 1958: 42 –43 (redescription, illustration) Bittacomorphella nipponensis Alexander, Nakamura & Saigusa 2009: 275 , 277 (redescription, illustration)

Diagnosis. Adult ( Figs. 7 i, 17a–f). Legs with two white bands, first located at proximal apex of tibia, second of 1st, 2nd, 3rd & 4th tarsomeres. Epandrium bilobate, lateral margins largely straight with convergent angle towards posterior margin; parameres spinelike, extend posteriorly past aedeagus.

Description. Larvae and pupae unknown. Adult. Measurements (n=3). Overall length 10.45mm (9.68– 11.16mm); head width 0.70mm (0.58–0.89mm), height 0.66mm (0.52–0.80mm), length 0.44mm (0.38–0.51mm); antenna flagellum length 8.96mm, antenna flagellomere proportions 1.00, 0.73, 0.96, 1.04, 1.04, 1.00, 0.93, 0.93, 0.89, 0.84, 0.76, 0.68, 0.68, 0.68, 0.60, 0.54, 0.50, 0.10; maxillary palpus length 1.95mm, segment proportions 0.28, 1, 1.52, 0.96, 3.68; thorax length 1.36mm (1.20–1.61mm), height 1.27mm (1.10–1.51mm); wing length 6.45mm (5.19–8.30mm), width 1.20mm (9.94– 1.58mm), R3+4+5 stem 0.53mm straight, R4+5 stem 2.08mm, R4 after fork 1.34mm, R5 after fork 1.21mm, R3+4+5:R4+5-stem:R4 1.00, 3.92, 2.52; r-m 0.29mm, M distal to r-m 3.13mm, Mdistal:R3+4+5 5.90, 1.00; R4:Mdistal 0.42, 1.00; CuA2 1.37mm; leg proportions, femur 1.0, 1.03, 1.14mm; tibia: 0.95, 0.94, 1.11; tarsomeres, foreleg 0.76, 0.24, 0.14, 0.03, 0.04; midleg 0.63, 0.23, 0.14, 0.03, 0.03; hindleg 0.75, 0.27, 0.17, 0.02, 0.03; abdomen length (n=2) 9.27mm (8.32–10.23mm), male tergite proportions 1.00, 3.63, 2.22, 1.92, 1.75, 0.81, 0.27; male genitalia width 0.67mm, height 0.81mm. Frons medial suture faint extending between antenna bases. Antennal scape with five setiform sensilla subdorsally along anterior margin; 18 Flagellomeres. Face subquadrate, shallowly incised by clypeus. Clypeus with lateral margins somewhat pinched at junction with face, narrowing at apex, not inflated. Hypopharynx subconical triangular, directed anteroventrally. Labium extending beyond clypeo-labrum. Labella fused medially, forming pad. Antepronotum with U-shaped dorsomedial- notch. Scutum glabrous, shining, ruddy-brown to black sometimes with muddy yellow highlighting at anterior corners; fold at rear of scutum, small ovoid prescutellum present. Scutellum muddy yellow, ovoid. Mediotergite olivaceous. Paratergite narrow, ovoid. Anepisternal cleft triangular in shape, anterior point slightly tapered, well sclerotized; anepisternal suture complete, extremely weak. Metapleuron with straight complete suture, setose prominence below halter. All pleurites ruddy brown to black. Wing membrane with limited macrotrichia at extreme apex of cells R1, R3, R4, R5; veins C to wing apex, Sc, R s, R1, R3, R4 & R5 after forking and distal portion of M with macrotrichia; alula undeveloped. Posthalter short, closely associated with posterior webbing. Coxae yellow, overall leg coloration brown. Two white bands, first at proximal apex of tibia, second at 1st, 2nd, 3rd & 4th tarsomeres. Empodium shallowly notched posteriorly. Abdomen brown. Male. Epandrium bilobate, trapezoidal, 1.5x as wide as long, internal folds absent; epandrial lobe subpentagonal, posterior margin straight, base of lateral margins straight, parallel, closely pressed medially, medial margin directed laterally at abrupt angle at 1/2 length in straight line, lateral margin angled medially at 2/3 length, apex of epandrial lobe offset laterally; posteriomedial stylus spinelike with rounded point. Epiproct prominent, web-like, sub-emarginate on posteriorly. Hypoproct ovoid. Epandrial claspers along lateral margen, directed ventroposteriorly, tapering to acute point curved dorsally. Subepandrial sclerite divided, fused to medial base of epandrial clasper, expanding to rounded apex. Parameres glabrous, laterally compressed, distal portion of paramere curving subobtuse dorsally, tapering to acute point. Gonocoxite conical, expanding to gonostylus, 2/3 length of gonostylus. Gonostylus rounded at tip, inner apex sensilla single row of 11 along distal 2/3, traversing from directly medial at posterior apex towards dorsal surface anteriorly. Gonopods closely associated with hypandrium Basal division of hypandrium bandlike, with gonocoxite set in trough. Terminal division weakly articulated, pouchlike, incising basal division, margins cupped dorsally, terminating in blunt triangular point. Sperm pump as described for sub-family; ejactulatory apodeme large for Bittacomorphinae , arcing prominently at base, tapering near apex. Lateral ejaculatory process with lateral section triangular winglike, not curved anteriorly, medial portion of posterior margin obliquely angled anteriorly towards aedeagal sclerites, posterior tooth present on posterior margin; ventral section triangular, medial margin heavily sclerotized, lateral extremity joining lateral section as ridge. Aedeagual sclerites tapering, sclerites widely separated, only 2x length width of lateral ejaculatory process; apical apodeme without dorsal lobe, ventral lobes broad rounded lacrimiform when viewed dorsally. Subaedeagal sclerite with anterolateral apices forming trapezoidal plate internally, anterior margin weakly emarginated, ventral arm earlike; external section rounded broadly triangular, terminal section curved weakly dorsally. Female. Epigynium trapezoidal, delineation of epiproct absent, lateral margins broadly rounded at base, straight distally, medial suture absent; epiproct posterior margin straight. Cercus base tapered heavily, dorsal margin straight, apex narrowly rounded, ventral margin slightly convex, arced posteriorly; apex with short cylindrical nodule with single elongate trichoid sensilla; cercus epigynium ratio 0.75, 1, cercus height:length 3, 1. Hypoproct with apex broadly triangular, base not visible. Genital fork not visible. Hypogynium subhemispherical, base of hypogynial valves distinct as straight sulcus across hypogynium, hypogynial valves with rounded margins on either side of medial notch; medial notch small, narrow V-shape.

Type material examined. Holotype. JAPAN. FUKUSHIMA . Hinoëmata , Japan, 24.vii.1923, coll. T. Esaki, flying near surface of mountain stream. [pinned 1 ♀; USNM] . Paratype. JAPAN. FUKUSHIMA. Ozenuma , 26.vii.1923, coll. T. Esaki [pinned 1 ♀; USNM].

Other material examined. JAPAN. AKITA . Lake Tazuara , 13.vi.1951, coll. I. Ito [pinned 1 ♂; slide 1 ♂; USNM] ; Turunoya , 14.vi.1951, coll. I. Ito [slide: 1 ♂; USNM] . ECHIGO. Kurukawa , 15.viii.1954, coll. K. Baba [pinned 2 ♂; slide 1 ♂; USNM] .

Taxonomic Notes. Bittacomorphella nipponensis is separable from other Bittacomorphella by the combination of two leg bands, dark 4th and 5th tarsi, and a bilobate epandrium.

Distribution. Fig. 20 b.

Figures

FIGURE 7. Bittacomorphine male wings. a. Bittacomorpha clavipes; b. Bi. occidentalis; c. Bittacomorphella pacifica Alexander; d. Bl. sackenii Von Röder; e. Bl. furcata sp. nov.; f. Bl. esakii Tokunaga; g. Bl. fenderiana; h. Bl. jonesi Johnson; i. Bl. nipponensis Alexander; d. Bittacomorphella thaiensis Alexander. All scale bars 1 mm except “ b ” (2 mm).

FIGURE 20. Asian Bittacomorphella distributions. a. Bl. thaiensis (star) and Bl. esakii (circle); b. Bl. nipponensis. Stars indicates type locality.