Bittacomorpha Westwood, 1835

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 : 27-30

Bittacomorpha Westwood, 1835

Bittacomorpha Westwood, 1835: 281 (original description, type species Bittacomorpha clavipes Fabricius ) Bittacomorpha Westwood, Alexander 1919: 790 (catalog)

Bittacomorpha clavipes Fabricius, Alexander 1920: 783 –784 (redescription) Bittacomorpha Westwood, Alexander 1927: 9 –10 (catalog)

Bittacomorpha Westwood, Alexander 1965: 98 (catalog)

Diagnosis. Larva ( Figs. 5 a–b, 6a–d). Head rounded, not deflexed, cranium domed, postgena with lateral lobes on anterior margin. Thoracic segments successively increasing in size posteriorly. segments with rows of cylindical tubercles. Anal division conical, respiratory siphon partially rectractable. Pupa. Right respiratory organ hypertrophied. Adult ( Figs. 7 a–b, 9, 10). Head ovoid, clypeus extremely narrow and acute, 1 st tarsomere inflated on all legs.

Description. Larva. Head capsule not deflexed, rounded, dorsal surface flat or convex; frontoclypeal apotome 2.5x as long as wide, narrowing subacutely anterior to antennae, anterior margin blunt forming acute triangle directed posteriorly, reaching to collar of genae; gena with anterior margin square, ventroposterior margin weakly and broadly emarginated, weak collar along posterior margin; postgena with two lobes located laterally on anterior margin. Thoracic segments successively increasing in size posteriorly. Abdominal segments cylindrical, homogenous in width, delineations between segments weak; segments with rows of tubercles, base mound-like with cylindrical apex, having elongate branching sensilla, lateral margins of tubercle with smaller branching sensilla. Anal division conical, respiratory siphon partially rectractable, annulations weakly developed if present.

Adult. Head ovoid, frons medial suture strong, extending between antennal bases to dorsal margin of face. Scape with five trichoid sensilla near dorsal margin, pedicel with scattered dorsally directed setae; 19–20 flagellomeres. Clypeus variable. Maxillary palpus as described for subfamily. Hypopharynx variable. Labium extending well beyond apex of clypeus. Labella fused medially, forming circular pad. Antepronotum platelike, narrowing obtusely dorsally. Scutum glabrous, shining or pollinose, black with white marking medially posterior to transverse suture. Prescutellum absent. Scutellum pale yellow, ovoid with parallel lateral margins. Mediotergite black, weak pollinosity, dense patches of setae at anteriodorsal margin, and two parallel lines of setae medially. Paratergite crescent-shaped, ventral margin straight. Sub-paratergal membrane inverse triangular, with sclerotized band near anterior spiracle, otherwise poorly sclerotized; anepisternal suture incomplete. Laterotergite D-shaped. Suture between epimeron and metapleuron distinct dorsally and ventrally, obscure near posterior spiracle; metapleural suture well developed, complete, straight to halter; no prominence or setae below halter. All pleurites with opaque, sky blue pollinosity, surface black. Wing length 5x width, alula undeveloped, membrane without macrotrichia. Halter and prehalter as described for subfamily, posthalter well developed, nearly twice as long as wide, largely free of webbing to posterior membranous association of halter. Coxae pollinose blue, fading to light yellow at trochanter, lateral surfaces with long setae; proximal portion of femur yellow, darkening to black at tibial joint. White band sub-proximally on tibia, expanding slightly to 1 st tarsomeres . First tarsomere greatly expanded, ovoid, upper margin with white band. 2nd & 3rd tarsomeres white, 4th & 5th black. Empodium diamond-shaped, notched proximally. Adominal segments black, posterior and lateral margins yellow. Male. Epandrium twice as wide as long; quadrate, broadly emarginate posterior margin, posterior apices obtusely rounded, internal fold prominent; posteromedial stylus downward directed triangular lobe medially; epiproct absent, hypoproct ovoid. Epandrial claspers articulate subapically at posterolateral corners, directed posteriorly, curved medially; tapering to blunt apex, medial surface flattened with numerous blunt conical sensilla. Parameres broad, glabrous sclerotized medial margin; medial membrane of paramere extending nearly to apex. Gonocoxite conical, expanding to gonostylus, 2/ 3rds length of gonostylus. Gonostylus rounded at tip. Basal division of hypandrium a hemispherical band, junction with terminal division membranous; gonocoxite not closely associated. Terminal division well articulated, lateral lobes present, posterior margin from weakly emarginate to convex. Superaedeagal membrane inflated. Sperm sac as described for subfamily; ejactulatory apodeme spathate, not tapering to rounded apex. Lateral ejaculatory processes with peduncle at base, triangular, discoid apodeme reduced, sclerotized ridge outlining lateral and dorsal margin. Aedeagal sclerites weakly tapering, apical apodeme dorsal lobe present, hooked posteriorly at apex, subaedeagal sclerite with internal portion platelike, poorly sclerotized anteriorly, ventral arm emerging from lateral margin, curving weakly ventrally; external portion triangular, directed dorsoposterior. Female. Epigynium lateral margins straight, posterior margin weakly visible at fusion with epiproct; epiproct tapering to cerci; cercus base indistinct, apex with buttonlike nodule with stout elongate trichoid sensilla centrally, ring of three finer sensilla arranged equidistant.

Figures

FIGURE 5. Larval habitus. a. Bittacomorpha clavipes Fabricius, lateral view (inset = dorsal view of head); b. Bi. occidentalis Aldrich, lateral view; Bittacomorphella fenderiana Alexander, dorsal view. Scale bars 1 mm (a, b), 2 mm (c).

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).