Elongeuma chichkan, Gordana & Ambros, 2022

Golovatch, S. I. & Spelda, J., 2022, Review of the Central Asian millipede genus Elongeuma Golovatch, 1982, with descriptions of two new species (Diplopoda: Chordeumatida: Kirkayakidae), Arthropoda Selecta 31 (1), pp. 1-9 : 6

Elongeuma chichkan sp.n.

Figs 2 , 19–23 , Map.

Elongeuma sp. 3 — Read, Golovatch, 1994: 61, 62 (R, M).

HOLOTYPE ♂ (+ micropreparation) ( ZMUM), Tien-Shang (= Tian Shan) Mts, Kyrgyzstan (= Kirghizia), Suusamyr Too Mt. Range , Chichkan River valley S of Alabel Pass , 1,700 m a.s.l., Betula & Juniperus forest, 2.VI.1993, S.I. Golovatch leg .

PARATYPES: 3 ♀♀, 1 ♂ juv., 1 ♀ juv ( JSP180121-007 , 008 , 009 , 010 , 011 ), same locality and date, leg. S.I. Golovatch.

NAME. Named after the type locality, Chichkan River , meaning “a small mouse” in the Kirghiz language.

DIAGNOSIS. Differs from congeners by the particularly strongly reduced posterior gonopods usually lacking any traces of a telopodite, and by the structure of ♂ leg-pair 7 (see also key below).

DESCRIPTION. Length ca 9 (♂ holotype) or 9–10 mm (♀ paratypes), width 0.85 (♂ holotype) or 0.9–1.0 mm (♀ paratypes).

All characters as in E. reductum sp.n., except as follows.

Coloration more regular, less contrasting/vivid ( Fig. 2 ). ♂ leg-pairs 3–6 more distinctly enlarged, with tarsal papillae distally; ♂ legs 7 ( Fig. 19 ) with greatly enlarged coxites each carrying a caudoparabasal knob and a strongly reduced, 2-segmented telopodite directed dorsolaterad, devoid of tarsal papillae; several pairs behind gonopods ( Fig. 20 ) likewise with a ventral row of strong and spiniform setae on both femur and, especially, prefemur.

Anterior gonopods ( Figs 21, 22 ) much like in E. reductum sp.n., vs hl being slender and finger-shaped in E. reductum sp.n., semi-circular with a basal constriction in E. chichkan sp.n., and linguiform and blunt in E. speophilum , also differing in the absence of a lobule (j) on each solenomere (sl). Posterior gonopods ( Fig. 23 ) much more like in E. speophilum , coxites quite high, densely setose, caudoparabasal excavation very deep, each with a coxal pouch or sac (cs) with a strong coniform projection medially.

Operculum of vulva with a similar, but stronger beak-shaped structure behind operculum, this structure being directed caudad, not caudolaterad ( Fig. 2 ).

Figures

Figs 1, 2. Habitus of Elongeuma reductum sp.n., # paratype, and Elongeuma chichkan sp.n., $ paratype, lateral views. Photographs by K.V. Makarov, taken not to scale Рис. 1, 2. ОбЩий вид Elongeuma reductum sp.n., паратип #, и Elongeuma chichkan sp.n., паратип $, виды сбоку. Фотографии К.В. Макарова, снЯты беЗ масШтаба.

Figs 19–23. Elongeuma chichkan sp.n., # holotype: 19 — legs 7, posterior view; 20 — legs 10, posterior view; 21, 22 — right anterior gonopod, mesal and posterior views, respectively; 23 — posterior gonopods, posterior view. Abbreviations: cs — coxal sac vestige; hl — hyaline lobe; pfl — pseudoflagellum; sl — solenomere; st — sternum. Scale bar: 0.1 mm. Рис. 19–23. Elongeuma chichkan sp.n., голотип #: 19 — ноги 7, сЗади; 20 — ноги 10, сЗади; 21, 22 — правый передний гонопод, соответственно иЗнутри и сЗади; 23 — Задние гоноподы, сЗади. ОбоЗначениЯ: cs — остатки коксального кармана; hl — гиалиноваЯ пластина; pfl — ложный жгутик; sl — соленомер; st — стернит;. МасШтаб: 0,1 мм.