Rhabdochaeta drewi Maneesh & Hancock, 2025

Rhabdochaeta drewi Maneesh & Hancock , sp. nov.

(figs 12–13)

Diagnosis: A small ( 3.12 mm) species characterized by concave face with a medial black spot, triangular black patch on facial margin, circular black spot between anterior frontal setae and compound eye, flagellum almost as long as width of compound eye, scutum darker with yellowish postsutural lateral vittae and yellowish subtriangular patch before scutellum. Stout, curved, long and erect white apical scutellar setae. Wing with black and white rays anteriorly and 8 bullae centrally. Abdomen yellowish with black bands on each tergite, oviscape yellow with basal and apical black bands. Aculeus basally broader and medially curved like a long melon.

R. drewi Maneesh & Hancock , sp. nov. is similar to R. pulchella de Meijere and R. gladifera Hering in general appearance but can be differentiated by having 2 dark oval bullae in cell r 2+3, basal white spots in cell m, white rays between each black ray in cells r 1 and r 2+3, 6–7 circular hyaline indentations in cell cu 1, thorax with lateral postsutural yellowish vittae, black scutum and by erect curved and thicker apical setulae on scutellum rather than long and thinner white setulae. Oviscape with black band and aculeus tip chisel shaped without triangular apical portion present in R. pulchella and R. gladifera ( cf. David et al. 2022b fig. 38).

Rhabdochaeta drewi sp. nov. is also similar R. mucronata Hering View in CoL , R. bakeri Bezzi View in CoL and R. assidua Ito View in CoL in general appearance; however, Hardy and Drew (1996) synonymised all three species with R. pulchella View in CoL based on examination of numerous specimens and types, but Hancock et al. (2021) treated R. mucronata View in CoL as distinct; it also differs from R. drewi in wing pattern details ( cf. Freidberg 2002 fig. H; Hancock et al. 2021 fig. 90). Based on observations by Hardy (1973 fig. 141; 1974 fig. 120), R. bakeri View in CoL also lacks basal white spots in cell m, has a fulvous abdomen and triangular apex of aculeus, clearly suggesting it is R. pulchella View in CoL .

Hardy & Drew (1996) synonymized R. bakeri View in CoL based on series of specimens and aculeus shape & length (triangular at apex and narrow basally: cf. Hardy 1973 fig. 141a; Hardy 1974 fig. 120d), also suggesting that it is possibly variation in R. pulchella View in CoL . However, if R. bakeri View in CoL is assumed to be distinct from R. pulchella View in CoL then it can also be separated from R. drewi sp. nov. by its face, scutum, abdomen, shape & length of aculeus. Rhabdochaeta drewi sp. nov. can be differentiated from R. bakeri View in CoL by triangular black spots on facial carina & a circular black spot just above it, scutum darker with two lateral yellowish orange vittae & prescutellar triangular spot, narrower marginal fuscous & white rays on wing, broader hyaline indentations in cell m, abdomen brownish with broad black bands, smaller aculeus, melon shaped, basally broad and with medial curvature which is longer, basally narrower & apically almost triangular in R. bakeri View in CoL ( cf. Hardy 1973 fig. 141a; Hardy 1974 fig. 120d).

Hardy and Drew (1996) discussed the variation in the abdominal pattern and black basal band on oviscape but shape of aculeus and spicules on distal eversible membrane clearly separates R. drewi from R. pulchella . Most Indian Rhabdochaeta have aculeus with triangular apical portion with lateral node like prominent constrictions on lateral margins ( David et al. 2022b). Such constrictions are less prominent in R. gladifera but apical portion triangular and tip of aculeus rounded.

Head: Pale yellowish, frons slightly darker above lunule, ocellar triangle yellow-brown, antennae 0.65 mm long pubescent and yellowish, scape with 1 stubby white and 2–3 black setulae dorsally, pedicel with 4–6 black setulae dorsally, flagellum ( 0.44 mm) elongate, slightly curved dorsally, pointed apically (fig. 12B), arista yellowish, shiny and densely pubescent. Circular supraoccular black spot just below stubby white frontal seta and a broad triangular black spot on either side of facial margin (fig. 12B). Face concave between carina and oral margin with a medial black spot (fig. 12B). Palpi elongate and fringed with stout black setulae resembling a chainsaw. Setae: 3 outer frontal (anterior small and stubby white, posterior longer, striated and lamellate), 1 inner frontal (stubby white), 2 orbital (translucent and lightly lamellate), 2 vertical (inner longer and slightly lamellate, outer vestigial), 1 preocellar (lamellate and white), 1 ocellar (stubby white), 2 postocellar (stubby white, medial longer than ocellar seta), 7–8 stout black and 2–3 stubby white postocular, 6 genal (1 black and 5 whitish translucent), postgena with dense black as well as white setulae (fig. 12B).

Thorax: Covered with stubby white erect setulae, dull black except postpronotal lobe, notopleuron, postsutural lateral vittae, scutellum and triangular patch on scutum just before scutellum yellow-brown. Erect white setulae as follows: 1 scapular and 4 just behind scapular, 2 just behind suture either side, 2 at apex of yellow prescutellar patch and 2 prescutellar behind prescutellar acrostichals. Erect white setae also present on scutellum: 1 above basal and 1 over apical setae, those over apical pair longer ( 0.44 mm) and stout. Postsutural lateral vittae end well before intra-alar setae, suture slightly brownish (fig. 12C). Pleura yellowish brown with black patches and covered with black and yellowish setulae, subscutellum, mediotergite, anepisternal stripe, anepimeron, katerpisternum, katatergite and anatergite dull black (fig. 12E). Setae: 1–2 postpronotal (2 on right side), 2 notopleural (posterior black and smaller than anterior), 1 presutural supra-alar (black), 1 postsutural supra-alar (yellowish), 1 dorsocental (anterior to postsutural supra-alar), 1 prescutellar acrostichal, 1 postalar, 2 scutellar (apical very small), 1 anepisternal, 1 anepimeral, 1 katepisternal.

All legs yellowish except fore femora with 1 ring-like black patch and a row of 3–5 setae on ventrolateral side (apical 2 setae black, the rest white) (fig. 12A), mid and hind femora with 2 black ring-like patches basally and apically, hind tibiae with apical black ring like-patch and row of 6–7 setulae on lateral side.

Wing (fig. 12F) 3.09 mm long, hyaline with brownish rays and dark brownish bullae. Cell bc hyaline, humeral crossvein black apically, cell c with narrow black longitudinal line in middle, Sc break black and cell sc with black longitudinal line. Cell r 1 with 3 brown rays filled with whitish indentation and 2 white rays, the first brown ray confluent with vein R 1. Cell r 2+3 with 3 brown and 1 white rays, cell r 4+5 with 1 incomplete and 1 complete brown rays confluent with vein R 4+5. Vein M with a brown ray, cell m with 4 black fulvous rays, the posterior ray broader and confluent with vein Cu 1. Cell cu 1 largely fulvous to brown with numerous hyaline spots and 3 marginal hyaline indentations. All rays white-filled atleast basally except rays not connected to others in cells r 4+5 and m and in cell cu 1. Central portion of wing brown with 7 distinct dark brown bullae and posterior portion in cell cu 1 and anal lobe with many small circular hyaline indentations. Bullae as follows: 2 oval shaped in cell r 2+3, 2 in cell r 4+5 (the anterior one with tiny apical pale spots), 1 almost circular in cell m just below vein M curve, 2 in cell dm (the anterior one larger, oval and shiny below r-m crossvein and the other irregular shaped at base of bm-cu crossvein) and 1 small oval shaped in front of cell bcu in cell cu 1. There are several circular hyaline or pale spots plus whiter spots surrounded by brown patches in cells br, r 4+5, dm and m.

Abdomen: All abdominal tergites yellowish and setose with whitish setulae, each tergite with lateral transverse black bands narrowing at margins. Bands almost connected medially leaving narrow yellowish area except on tergites IV and V, where yellow area broader (fig. 13A). Black and white setae (inner 2 black, outer 6 whitish) on posterior margin of tergite VI.

Genitalia: Oviscape 0.78 mm long, yellowish with broad basal and narrow apical black bands, aculeus 0.77 mm long, melon shaped, basally broad and with medial curvature (fig. 13B). Tip of aculeus chisel shaped, sharper at apex. Spicules on distal eversible membrane irregularly oval and widely spaced. Two distinct types of spicules present on mid eversible membrane: stout triangular and semicircular, both types tightly spaced (fig. 13D). Spermathecae not examined.

Type Material: Holotype ♀, Solan Bait, INDIA, Himachal Pradesh, Solan, Nauni , 30°51’47” N 77°10’7” E. 03.vii.2023, Maneesh Leg. at Zoological Survey of India ( High Altitude Regional Centre ( HARC), Solan , Himachal Pradesh) GoogleMaps . Paratype 1 ♀, same data as holotype GoogleMaps .

Etymology: This species is named after Prof. R.A.I. Drew for his tremendous contributions to the work of Tephritidae .