Bittacomorphella thaiensis Alexander 1953

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 : 55-56

Bittacomorphella thaiensis Alexander 1953

Bittacomorphella thaiensis Alexander, 1953: 98 –99.

Diagnosis. Adult ( Figs. 7 j, 17g –h). Clypeus length and width subequal, maxillary palpus reduced for four segments; wing without macrotrichia, legs with white confined to 2nd & 3rd tarsomeres.

Description. Larvae and pupae unknown. Adult. Measurements (n=1). Overall length 10.45mm; head width 0.72mm, height 0.65mm, length 0.47mm; antenna flagellum length (female) 2.89mm, flagellomere proportions 1.00, 0.90, 0.90, 0.90, 0.90, 0.90, 0.81, 0.86, 0.72, 0.72, 0.68, 0.72, 0.72, 0.59, 0.59, 0.5, 0.5, 0.14; maxillary palpus length 0.81mm, segment proportions 0.09, 1, 1.28, 1.47; thorax length 1.28mm, height 1.54mm; wing length 6.80mm, width: 1.37mm; leg proportions, femur 1.0, 1.08, 1.20; tibia 0.95, 0.97, 1.06; tarsomeres, foreleg 0.65, 0.21, 0.15, 0.02, 0.02; midleg 0.57, 0.18, 0.12, 0.03, 0.03; hindleg 0.75, 0.23, 0.15, 0.02, 0.02; abdomen length: 7.80mm. Frons medial suture weakly developed. Antennal scape with three setiform sensilla midway along anterior margin; 18 Flagellomeres. Face narrow, incised by clypeo-labrum to antennal bases. Clypeous broad, lateral margins narrowing beyond eye, length and width subequal. Maxillary palpus reduced to four segments. Hypopharynx triangular flattened, directed anteriorly. Labium xtending beyond clypeus. Labella D-shaped partially fused medially, forming pad. Antepronotum weakly developed, low ridge. Scutum glabrous, chocolate brown; prescutellum absent. Scutellum subcircular, muddy yellow. Mediotergite ruddy-brown, pollinose. Paratergite ovoid tapering at apices. Anepisternal cleft triangular, extending anteroventrally, well sclerotized; anepisternal suture absent. Suture of epimeron and metapleuron discernible only ventrally. Metapleural suture complete, sinuous arc; setose prominence below halter. Pleurites glabrous chocolate, with reduced pollinosity. Macrotrichia absent from wing. Alula absent. Posthalter poorly developed bump. Coxae yellow, overall leg coloration brown; single white band confined to distal tip of 1st, 2nd & 3rd tarsomeres. Empodium notched posteriorly. Abdomen light brown. Female. Epigynum flat, subtrapezoidal tapering towards posterior margin; posterior margin straight. Cercus with dorsal margin straight, ventral margin straight posteriorly, narrowing at base, apical sensilla not evident; cercus to epigynium ratio 1.25, 1; cercus height:length 1, 3; narrowing at base. Hypoproct and genital fork not visible on specimens examined. Hypogynium narrow, posterior corners truncate triangular lobes; medial knoblike prominence centrally located just below posterior margin, hypogynial valves weakly developed, medial notch absent.

Material examined. Holotype. THAILAND. CHIANG MAI. Doi Chom Cheng , 3000 ft., 1.i.53, coll. Prayoon C. Paratype. Same as holotype [pinned 1 ♀; USNM].

Taxonomic notes. Bittacomorphella thaiensis is readily separated from other Bittacomorphella by the combination of a wing membrane lacking macrotrichia and one white band on the leg. Alexander’s 1953 description notes that the paratype has a locality of, “Near Wat at Doi Sutep, Chengmai, February 1953 (Deed C. Thurman).” However, the paratype is labeled with the same locality as the holotype.

Distribution. Fig. 20 a.

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.