Cladotanytarsus

Puchalski, Mateusz & Giłka, Wojciech, 2017, Cladotanytarsus Kieffer (Diptera: Chironomidae): several distinctive species reviewed on the basis of records from Canada and USA, Zootaxa 4242 (2), pp. 344-358 : 352

Cladotanytarsus sp.

( Fig. 4 )

Material examined. USA. ILLINOIS . Du Bois, 24 April 1914, 1 male hypopygium (S66-1261). LOUISIANA . New Orleans, 14 May 1952, 4 male hypopygia (S64-818, 821, 822, 823). Main body parts missing. Ex coll. M. & J.E. Sublette (legator unknown). Deposit in DEUM.

Diagnostic description. Adult male (n = 5, hypopygia).

Hypopygium ( Fig. 4 ). Gonostylus shorter than gonocoxite, ca. 85 µm long, with apex pointed. Anal tergite with V-type separated bands and 7–9 median setae placed in two irregular rows. Anal point with parallel-sided distal elongation, apically blunt or rounded, bearing 3 spinulae at most or spinulae absent ( Fig. 4 A, C). Superior volsella horn-shaped, with pointed apex, bearing field of microtrichia on 2/3 basal part or basal half at least, 5–8 dorsal setae and 3 long setae placed on conical tubercles at base. Digitus straight or very slightly curved, apex narrow, extending far beyond superior volsella ( Fig. 4 A, D). Stem of median volsella stocky, ca. 30 µm long, shorter than its longest lamellae, bearing several setiform and 6–7 branched lamellae (4 strong and 2–3 weaker) ( Fig. 4 B, E). Inferior volsella as drawn in Fig. 4 F, strongly broadened at base, with distinct round margin on ventral side, dorsomedian ridge thin ( Fig. 4 A, B, F).

Remarks. Among the oldest specimens sampled from the Sublettes’ collection we found several male hypopygia belonging to a species which, in view of the set of diagnostic characters, deserves to be presented. The slender anal point with the parallel-sided distal elongation, the horn-shaped superior volsella, the stocky stem of the median volsella bearing stout branched lamellae and the inferior volsella strongly broadened at the base may indicate a close similarity to Cladotanytarsus donmcbeani Langton et McBean, 2010 (cf. Fig. 4 and Langton & McBean 2010, figs 1– 4). According to the original description (op. cit.), these two Cladotanytarsus species differ as adult males in the presence/absence of anal point spinulae and the shape of the digitus, apically hooked in C. donmcbeani .

Figures

FIGURE 4. Cladotanytarsus sp., male. A, B — hypopygium in dorsal (A) and ventral aspect (B); C — anal point (variation); D — superior volsella and digitus (variation); E — median volsella (typical structure); F — inferior volsella (typical structure) (D—magnified ca. 2 times relative to A; E, F—magnified ca. 3 times relative to A).