Plectrocnemia kirmikhia Melnitsky, Ivanov & Perkovsky, 2021

Melnitsky, Stanislav I., Ivanov, Vladimir D. & Perkovsky, Evgeny E., 2021, A new species of Plectrocnemia (Trichoptera: Polycentropodidae) from Rovno amber, Zootaxa 5006 (1), pp. 106-109 : 107-108

Plectrocnemia kirmikhia Melnitsky, Ivanov & Perkovsky , sp. nov.

Figs 1–2

Diagnosis. The new species has very large aedeagus provided with dorsal teeth, well developed preanal appendages with anteroventral projection, and complicated inferior appendages with club-like protuberance directed upwards. It resembles P. protensa Ulmer, 1912 from Baltic amber in a few features: enormously developed aedeagus bears spines although its configuration and shape of spines are different; other parts of genitalia are also unlike this species. P. kirmikhia differs from P. protensa also in the shape of the inferior appendages that have an attached process in the first species and simplified plate in the second; the presence of a clavate process directed upward which is absent in P. protensa and the shape of the preanal appendages, which are elongated with a short ventral pointed branch in the new species and undeveloped in P. protensa .

Description. Abdomen, thorax and wings brownish-yellowish. Legs and head gray-brown. Head with dark hairs. Antennae shorter than forewings.

Male genitalia. The inferior appendages of unusual shape, short, strongly sclerotized; the terminal part of gonocoxite with rounded apex, middle part with clavate process (probable gonostyle) directed upwards and covered with strong hairs. Dorsal part of segment IX membranous. The preanal appendages (cerci) oblong with small ventral pointed process. Aedeagus massive and long, with 4 thick, curved spines on the dorsal surface and sclerotized apex.

Measurements. Holotype: body length 4.5 mm; forewing length 5.1 mm.

Holotype ♂, SIZK LKV –460, Rovno Amber , late Eocene. Syninclusions: SIZK LKV –459 Trichoptera, SIZK LKV –461 Aranei.

Etymology. The species is named in honor of the Russian arachnologist and publisher Kirill Glebovich Mikhailov, of Zoological Museum of Moscow University, Russia.

Distribution. Priabonian Rovno amber, Ukraine.

Comment. Major part of the amber material on Plectrocnemia was described on older collections and the types are mostly lost. Hence the only opportunity to make diagnosis is to compare with other species known mostly from the Ulmer (1912) monograph and subsequent publications. The new species is taxonomically remote from all known Plectrocnemia species because of extremely voluminous aedeagus with dorsally pointed tooth, and unique shape of inferior appendages combined with characteristic preanal appendages provided with posteroventral process.

Figures

FIGURE 1. Plectrocnemia kirmikhia sp. nov.: 1A, general view, dorsal; 1B, general view, ventral; 1C, male genitalia, lateral. (Scale bars: 1A, 1B = 1 mm; 1C = 0.5 mm)

FIGURE 2. Male genital structures of Plectrocnemia kirmikhia sp. nov. Abbreviations. ae – aedeagus, ia – inferior appendages, pa – preanal appendages, s8 – segment VIII, s9 – segment IX.