Tianarinha, Irwin & Winterton, 2024

Irwin, Michael E. & Winterton, Shaun L., 2024, New genera of stiletto flies endemic to Madagascar (Therevidae: Therevinae), European Journal of Taxonomy 932 (1), pp. 1-33 : 17-18

Tianarinha gen. nov.

urn:lsid:zoobank.org:act:78C1EE66-7B0E-4F0F-8CE7-741BB69D1E90

Type species

Tianarinha micet gen. et sp. nov.

Diagnosis

Male and female with single row of postocular macrosetae and additional macrosetae scattered on occiput; prosternal setae present medially; one pair of scutellar macrosetae; setae absent on metanepisternum and posterior surface of mid coxa; wing vein R 1 with setulae along dorsal surface; wing cell m 3 open; radial and medial veins irregularly wavy towards wing margin.

Differential diagnosis

Tianarinha gen nov. is distinguished from Rinhatiana gen. nov. by the presence of a single pair of scutellar macrosetae (two pairs in Rinhatiana ) and prosternal setal present medially (absent in Rinhatiana ). Tianarinha is separated from all other genera of Therevinae in the region by the presence of setulae on the R 1 vein. In addition, it is separated from Schoutedenomyia by the presence of regular sized macrosetae on the foretibia (relatively small in Schoutedenomyia ). It is additionally distinguished from Stenopomyia and Stenosathe by the wavy radial and medial veins in the wing (straight or gradually curved in Stenopomyia and Stenosathe ).

Etymology

ʻ Tianarinha ʼ is a combination of the nicknames of two key personnel in Madagascar who contributed significantly to the project on the Diptera of Madagascar. We have the honor naming this genus after Razafindratsita Vololontiana (also known as Tiana) and her spouse, Rasolondalao Harin’Hala Hasinjaka (also known as Rin’ha). Gender is female. See additional comments under Rinhatiana gen. nov.

Description

Relatively small individuals with glaucous pubescence and sparse vestiture.

HEAD. Length and height subequal; frons flat, gray and brown pubescent with dark band from inner eye margin to base of antenna; male frons width at narrowest point equal to ocellar tubercle width, frons width somewhat sexually dimorphic; inner margins of female eyes subparallel; parafacial without setae; postocular ridge of male and female in single row, additional scattered macrosetae on occiput; occiput pubescence gray or brown; gena rounded; antenna shorter than head, positioned on lower half of head, directed anteriorly; scape short, less than 3× pedicel length, cylindrical; flagellum turbinate, abruptly conical tapered, subequal to combined length of scape and pedicel, style apical, elongate; palpus slender; mouthparts short.

THORAX. Central depression of prosternum setose; cervical sclerite lacking macroseta; scutum covered with filiform setae, often of variable length; pleuron overlain with brown pubescence; metanepisternum with postspiracular setae absent; metakatepisternum setae absent; hind femur and tibia relatively short, approximately equal length in all legs; posterior surface of midcoxa without setae; posterior surface of hind coxa sometimes setose, hind coxal knob present; midfemur vestiture as filiform setae admixed with adpressed, lanceolate and scale-like setae; forefemur and midfemur with macrosetae absent; hind femur with single subapical anteroventral macroseta, posteroventral macrosetae absent; tibial macrosetae regular sized; scutal chaetotaxy (pairs): notopleural, 3; supra alar, 2; post alar, 1; dorsocentral, 1; scutellar, 1; wing smoky infuscate, mottled and darkened along wing veins; vein R 1 with setulae present; R 4 and R 5 irregularly wavy; medial veins with M 1 distinctly irregularly wavy; cell m 3 open, veins M 3 and M 4 separate to margin; wing membrane uniformly covered with microtrichia.

ABDOMEN. Relatively slender, slightly narrowed along length (male) or short, broad, slightly tapered (female).

TERMINALIA. Epandrium flat; gonocoxites separate medially with posteromedial margins proximal; inner gonocoxal process (igp) present, not articulated; outer gonocoxal process poorly developed as raised ridge; ventral lobe elongate, half length of gonostylus; dorsal apodeme of parameral sheath not fused laterally to gonocoxites; ventral apodeme as a single lobe, broad and sub-triangular; distiphallus narrow, directed ventrally; female tergite 8 elongate with anteromedial process; sternite 8 posterior margin emarginate posteromedially; acanthophorite setae as two sets (A1 & A2), A1 setae enlarged; spermathecal sac as a single lobe with spermathecal ducts originating on main spermathecal sac duct; two spermathecae.

Remarks

See remarks under Rinhatiana gen. nov.