Colocasiomyia oligochaeta, Zhang & Gao & Takano & Yafuso & Suwito & Meleng & Toda, 2023

Zhang, Guang, Gao, Jian-Jun, Takano, Kohei Takenaka, Yafuso, Masako, Suwito, Awit, Meleng, Paulus Ak & Toda, Masanori J., 2023, Phylogenetic classification and palm-inflorescence anthophily of the Colocasiomyia zeylanica species group (Diptera: Drosophilidae), with descriptions of five new species, Zootaxa 5278 (2), pp. 201-238 : 225-226

publication ID	https://doi.org/ 10.11646/zootaxa.5278.2.1
publication LSID	lsid:zoobank.org:pub:697AC989-141D-4A89-8F02-5A4644E303EA
DOI	https://doi.org/10.5281/zenodo.7906017
persistent identifier	https://treatment.plazi.org/id/03C687D9-FFCE-FFF9-A5C6-FAA9854AE605
treatment provided by	Plazi
scientific name	Colocasiomyia oligochaeta
status

Treatment

2. Colocasiomyia oligochaeta View in CoL species subgroup, new

Diagnosis. Antennal arista apically truncate, stick-shaped (ch.4-1; Fig. 3D, E View FIGURE 3 ). Proclinate, orbital setae absent (ch.8- 1; Fig. 2D, E View FIGURE 2 ). Anterior, dorsocentral setae absent (ch.26-2; Fig. 6D, E View FIGURE 6 ). Patch of supracervical setae present over basal portion of dorsolateral, tentorial apodeme (ch.13-1; Fig. 4D, E View FIGURE 4 ). Dorsolateral, tentorial apodemes distally strongly curved outward (ch.14-1; Fig. 4D, E View FIGURE 4 ). Palpus without prominent seta (ch.17-2; Fig. 5D View FIGURE 5 1, E 1 View FIGURE 1 ). 5x index> 4.0 (ch.32-2; Fig. 8D View FIGURE 8 2, E 2 View FIGURE 2 ). Hind tibia apicoventrally with two stout setae (ch.40-1; Fig. 9D View FIGURE 9 3, E 3 View FIGURE 3 ). Epandrium with neither pubescence nor setae (ch.53-1, ch.54-1; Fig. 11-2D, E).

Shared characters. Antennal pedicel grayish brown ( Fig. 14D, E View FIGURE 14 ). Eye with fine, sparse, interfacetal setulae (ch.7-0; Fig. 2D View FIGURE 2 1, E 1 View FIGURE 1 ). Outer, vertical setae absent (ch.9-1; Fig. 4D, E View FIGURE 4 ). Inner (convergent) vertical setae dislocated outside line of ipsilateral orbitals; posterior reclinate orbitals longest on head ( Fig. 2D 2, E 2 View FIGURE 2 ). Upper, postocular setae upright or up-curved (ch.10-1; Fig. 4D, E View FIGURE 4 ). Dorsomedial, tentorial apodeme reaching 1/5 to vertex ( Fig. 4D, E View FIGURE 4 ). Facial carina wider than 1st flagellomere, as long as pedicel + 1st flagellomere ( Fig. 2D 2, E 2 View FIGURE 2 ). Clypeus thicker than 1/2 length of cibarium ( Fig. 5D View FIGURE 5 1, E 1 View FIGURE 1 ). Cibarial, medial sensilla 2 per side; posterior sensilla absent (ch.21-3; Fig. 5D View FIGURE 5 2, E 2 View FIGURE 2 ). Labellum with 7 pseudotracheae (ch.24-0; Fig. 5D View FIGURE 5 1, E 1 View FIGURE 1 ). Postpronotal lobe with 1 prominent seta (ch.25- 2; Fig. 6D, E View FIGURE 6 ). Prescutellar, acrostichal setae absent (ch.27-1; Fig. 6D, E View FIGURE 6 ). Only one prominent katepisternal seta longer than acrostichal setulae (ch.29-2; Fig. 7D, E View FIGURE 7 ). Costal setae in middle row from 2nd costal section to proximal portion of 3rd section all weak, trichoid; sparse setae in upper row stout, longer, trichoid (ch.30-2, ch.31-1; Fig. 8D View FIGURE 8 1, E 1 View FIGURE 1 ). Patch covered with only minute pubescence present on anterodorsal portion of fore tarsomere I (ch.33-1; Fig. 9D View FIGURE 9 1, E 1 View FIGURE 1 ). Fore tarsomere II with 1 large and 1 small pegs; latter 1/3 as long as former (ch.37-1; Fig. 9D View FIGURE 9 1, E 1 View FIGURE 1 ). Mid tarsomere I as long as tarsomeres II, III and IV combined; hind I slightly longer than II+III+IV ( Fig. 9D View FIGURE 9 2,3, E 2,3). Claws as long as tarsomere V (ch.43-1; Fig. 9D, E View FIGURE 9 ). Abdominal tergites blackish brown ( Fig. 14D, E View FIGURE 14 ). All sternites longer than wide and I fused to II in both sexes (ch.45-2; Fig. 10D, E View FIGURE 10 ); male V not fused to VI, and VI completely bilobed (ch.46-0, ch.47-1; Fig. 10D View FIGURE 10 1, E 1 View FIGURE 1 ); female sternite VII more or less convex on distal margin (ch.51-2; Fig. 10D View FIGURE 10 2, E 2 View FIGURE 2 ). Female tergite VII mid-dorsally separated into 2 triangular, lateral plates (ch.52-0). Epandrial, ventral lobe differentiated (ch.56-1; Fig. 11-2D, E). Surstylus absent (ch.59-4; Fig. 11-2D, E). Hypandrial phragma anterior, strongly sclerotized rod-like portion (ch.68-2; Fig. 11-2D, E). Membranous aedeagus long, tube-like (ch.70-1; Fig. 11-2D, E). Phallal sheath not pubescent (ch.74-0; Fig. 11-2D, E). Phallapodeme articulated to and not shorter than phallal sheath (ch.75-0, ch.76-0; Fig. 11-2D, E). Hypoproct partly pubescent (ch.80-1; Fig. 12D View FIGURE 12 1, E 1 View FIGURE 1 ). Epigynium dorsally separated into 2 lateral lobes (ch.81-1; Fig. 12D View FIGURE 12 1, E 1 View FIGURE 1 ). Perineal membrane with patch of dense, distinct warts (ch.84-1; Fig. 12E View FIGURE 12 ). Hypogynial valve with trichoid sensilla on only distal portion; distal, narrow portion as long as basal, broad portion ( Fig. 12D, E View FIGURE 12 ).

Remarks. This species subgroup is well demarcated by a number of non-homoplastic synapomorphies ( Fig. 13 View FIGURE 13 ) defined as the diagnostic characters, especially the peculiar chaetotaxy that the proclinate orbital, outer vertical, and anterior dorsocentral setae are lacking. Such an anomaly from the basic chaetotaxy is rare in the Drosophilidae , but is seen in a few species of Colocasiomyia : C. crassipes (de Meijere) and C. micheliae of the crassipes group lack the outer vertical and dorsocentral setae ( Grimaldi 1991; Yafuso et al. 2000); and C. ecornuta Toda & Takano of the cristata group lacks the outer vertical setae ( Takano et al. 2021).

Included taxa. Colocasiomyia oligochaeta sp. nov., and C. grimaldii sp. nov.