Collessomma mongolica, Lukashevich & Blagoderov, 2020

Lukashevich, Elena D. & Blagoderov, Vladimir A., 2020, Review of Mesozoic Perissommatidae (Insecta: Diptera), Zootaxa 4718 (4), pp. 481-496 : 490-491

Collessomma mongolica sp. nov.

( Figures 4 F–G, 6)

urn:lsid:zoobank.org:act:C0792C71-7637-4CBC-8961-F7BBF51155EC

Holotype. PIN, No. 3559/10039, well-preserved impression of a female.

Type Horizon and Locality. Bon-Tsagan, Central Mongolia, south of the lake Bon-Tsagan-Nur (45°27’N 99°06’E); Khurilt rock unit, Barremian or Aptian.

Etymology. The species epithet refers to Mongolia.

Description. Body uniformly brown. Sc long, ends free distad of base of R 1; Rs stem twice as long as basal segment of R 5; R 4 2.5–3 times longer than R 3. Female cerci elongated, subequal to sternite VII and VIII combined, relatively sclerotized covered in short setae apically.

Measurements (mm). Female holotype: body length 2.9, head width 0.34, thorax length 0.78, abdomen length 1.98, female cerci length 0.29, wing length 2.9–3.5.

Material. Besides holotype, paratype PIN, No. 3559/4154 and 3559/3996 (part and counterpart of an isolated wing).

Figures

FIGURE 4. Collessomma gen. nov. A–C. C. sibirica gen. et sp. nov. A, B. Male? PIN No. 5026/206, wing and tarsus. C. Holotype PIN No. 5340/1681, male terminalia. D, E. C. gnoma gen. et sp. nov. Holotype PIN No. 5026/201, wing and male terminalia. F, G. C. mongolica gen. et sp. nov. F. Paratype PIN No. 3559/4154, wing. G. Holotype PIN No. 3559/10039, female terminalia.Abbreviations: aed, aedeagus; cerc, cerci; gst, gonostylus; gx, gonocoxite; TG6–9, tergites 6–9; ST6-8, sternites 6–8. Scale bars 1 mm (A, F), 500 μm (D), 200 μm (C, E, G), 100 μm (B).