Tanytarsus germani, Dantas & Amat & Hamada & Giłka, 2022

Dantas, Galileu P. S., Amat, Eduardo, Hamada, Neusa & Giłka, Wojciech, 2022, Towards the systematics and diversity of Neotropical Tanytarsus van der Wulp (Diptera: Chironomidae): news from Colombia, Zootaxa 5129 (4), pp. 505-529 : 510-511

Tanytarsus germani sp. nov.

LSID: urn:lsid:zoobank.org:act:EA7DEF24-FFB4-44E8-9A46-B11916895012

( Fig. 3A–F )

Type material. Holotype, adult male: COLOMBIA, Meta Department, Puerto Lopez , 04º08’11’’N 72º52’53’’W, 206 m a.s.l., 01–03 January 2021, Malaise trap, G.P.S. Dantas, S.M. R. Hernández (CETdeA) . Paratypes: 2 males, same data as for holotype .

Derivatio nominis. The specific name is a patronym commemorating the eminent Colombian entomologist, German Amat (1960–2021).

Diagnosis. Frontal tubercles absent. Tergite IX with 3–4 strong median setae and extensive microtrichia-free area near base of anal point. Anal tergite bands V-shaped, broadly separated. Anal point with a round pit—anteriorly enclosed with darkly pigmented horseshoe-like margin overlapping the crests; anterior bar cone-shaped, covered with scale-like thorny structures, darkly pigmented; posterior bar split into two flake-shaped projections turned up dorsolaterally. Superior volsella extensive, anterior margin straight, median margin strongly concave, posteromedian corner distinctly narrower but relatively strong. Digitus straight, pointed. Median volsella with single foliate and several setiform lamellae.

Description. Adult male (n = 3).

Body size and proportions. Total length 1.96–2.08 mm. Wing length 1.05–1.06 mm. Total length/wing length ratio 1.87–1.96. Wing length/length of profemur ratio 1.59–1.62.

Colouration. Eyes black.Antenna brown. Scutal vittae and postnotum light brown. Head capsule, ground colour of thorax, scutellum, sternum, and haltere yellow to light brown. Legs yellowish to light brown. Wing veins yellow, membrane pale. Abdomen yellow.

Head. Eyes bare, with well-developed dorsomedian extensions. Antenna with 13 flagellomeres; ultimate flagellomere 350–357 μm long; AR 0.83. Frontal tubercles absent. Tentorium 90–100 μm long. Temporal setae 6–7 on each side. Clypeus with 10–13 setae. Lengths of palpomeres 1–5 (in μm): 25–26, 25–28, 67–72, 80–90, 122–132; third palpomere with 5 sensilla clavata subapically, 10–12 μm long.

Thorax. Ac 14–16, restricted to anterior region of scutum; Dc 5–7 on each side, uniserial; Pa 1 on each side; Scts 5. Scutum projected and rounded anteriorly, overreaching antepronotum.

Wing. Obovate, with anal lobe strongly reduced. Almost all veins and entire membrane below radial veins covered with macrotrichia. Brachiolum with 1 seta. VRCu 1.25–1.33.

Legs. Foreleg tibia with short lanceolate spur 13–14 μm long. Tibial combs of mid and hind legs separated; spurs of mid leg unequal: one apically curved, 28–30 μm long, second straight, 12–15 μm long; spurs of hind leg unequal: one apically curved, 33–35 μm long, second straight, 30–33 μm long. Basitarsus of mid leg without sensilla chaetica. Lengths and proportions of legs as in Table 2.

Hypopygium. Tergite IX covered with dense short microtrichia except for extensive bare fields near base of anal point, with 3–4 median setae between anal tergite bands; lateral teeth minute; anal tergite bands V-shaped, medially separated, almost reaching the base of anal point ( Fig. 3A, C ). Anal point 40–45 μm long, lanceolate, apically rounded, bearing a round pit—anteriorly enclosed with dark pigmented, horseshoe-like margin overlapping the crests; anterior bar in shape of spruce cone, covered with scale-like thorny structures, darkly pigmented, posterior bar placed subapically on anal point, split into two flake-shaped projections turned up dorsolaterally ( Fig. 3A, C, D ). Superior volsella with anterior margin straight and median margin strongly concave, posteromedian corner or distal half distinctly narrower but relatively strong; 6 setae on dorsal surface, 2 setae on median margin (1 close to anterior margin) and 1 seta on ventral tubercle close to anterior margin, field of microtrichia on dorsal surface absent; digitus 10–12 μm long, straight, pointed, reaching but not extending beyond median margin of superior volsella ( Fig. 3A, B, E ). Stem of median volsella 17–20 μm long, slightly swollen distally, with several setiform lamellae placed subapically and single foliate lamella on apex ( Fig. 3B, F ). Inferior volsella 55–60 μm long, nearly straight, posteriorly directed, with distal half slightly swollen, apex round. Phallapodeme ~70–80 μm long; transverse sternapodeme ~40 μm long, with small oral projections. Gonocoxite 90–95 μm long. Gonostylus 80–85 μm long, straight, tapering towards blunt apex. HR 1.10–1.12, HV 2.42–2.45.

Distribution and ecological notes. The adult male specimens examined were collected together with those of three other species described in the present paper. For details on ecology and bionomics see notes under Tanytarsus colombiensis .

Figures

FIGURE 3. Tanytarsus germani sp. nov., male. A, B: hypopygium in dorsal (A) and ventral aspect (B); C: anal tergite and anal point; D: anal point in dorsal view; E: superior volsella and digitus; F: median volsella; (D–F magnified ca. 2–3 times relative to A and B).