Heteromurus Wankel, 1860

Baquero, Enrique, Potapov, Mikhail & Jordana, Rafael, 2021, New species and records of Entomobryidae and Orchesellidae (Collembola) from the East Caucasus (Russia), Zootaxa 4991 (2), pp. 247-270 : 265-268

Genus Heteromurus Wankel, 1860

Heteromurus nitidus ( Templeton, 1836) in Templeto n & Westwood, 1836

( Figs 9A–C , 10A–F )

Material studied. RUSSIA, North Caucasus: Ingushetia, Jairah District, Jairah-Sunja Track. Koloi Laam-Keli, Tetrkikali River Valley ( Assa River tributary), south slope, rarefied Koch pine and juniper needles (42.835882, 44.881411, 1640 m a.s.l.), 19.iv.2018 , hand collection, one in slide ( CAU 2018-15-02) and two in ethyl alcohol ( CAU 2018-15-03 and 04); Chechnya, Shalinsky District, Shali-Tevzana Track, Bass River Valley , old broadleaf valley forest, rotten wood and litter (43.067385, 45.881284, 329m a.s.l.), 21.iv.2018 , hand collection, five in ethyl alcohol (two with codes CAU 2018-28-02 and 03; one on slide ( CAU 2018-29-01) and three in ethyl alcohol ( CAU 2018-29-02 to 04). All Kuznetsova N., Potapov M. and Kremenitsa A. leg.

Description of specimens from Nord Caucasus. Body length (excluding antennae) 1.90mm, up to 2.30 mm. Ground color yellowish. Scales rounded as in Fig. 10C .

Head. Two eyes: AB ( Fig. 9A ). Antennae length 0.85mm, 2.2 times the length of the head; Ant IV without apical vesicle and with pin chaeta; distribution of ciliated chaetae, smooth chaetae, and sensilla as in Figs 10D–F ; subapical organite as a drumstick, with accompanying chaeta; sensory organ of Ant III with the special sensilla long-ovoidal (wider at its basis), and three guards additional sensilla; relative length of Ant I/II/III/IV=1/1.60/2.00/3.10. Prelabral and labral chaetae smooth. Labral papillae absent. Maxillary palp bifurcate, with three sublobal chaetae. Lateral process of labial papilla E surpassing the papilla tip. Labial posterior row with all chaetae smooth (mmrell), r 2/3 of m.

Body. Abd IV/III length ratio =1.45 (between 1.2–1.7). Trochanteral organ with approximately 10–12 chaetae. Tibiotarsus not sub-segmented, with smooth chaetae. Claw with two or three teeth: paired at 50 % and first unpaired (when present) at 75 % from basis; dorsal teeth basal ( Fig. 10B ). Empodium lanceolate, with a tooth on external lamella (pe) in leg III. Tenent hair acuminate. Length of manubrium and dens 0.32 and 0.5 mm, respectively (average for n =2). Manubrial plate with six chaetae and two pseudopores. Mucro with subapical tooth bigger than apical one, mucronal spine reaching the tip of the subapical tooth.

Macrochaetotaxy ( Figs 9A–C ). In this description, we intend to apply the dorsal macrochaetotaxy of Entomobryini to this species. Simplified Mc formula: 6-2-0-3-0/0-3/0-2/0-0-1/0-0-0-1-1. Head: H1 area with six Mc (An 2, An An 3a1, An 3a, and An 3; there is in addition a posterior chaeta to An 3a2); H2 area with two Mc (A 5 and A 6); H3 without Mc; H4 area with three Mc (S 1, S 3, and S 4i); H4’ area with three Mc (S 6, S 5, and S 4); H5 area without Mc. Mesothorax: area T1 without Mc; T2 with three Mc (a 5, m 4, and m 4p). Abdomen: AbdII area A1 without Mc, area A2 with two Mc (m 3ep and m 3e), no external Mc to bothriotrichum a 5, ‘as’ and ‘s’ present; AbdIII without Mc on A3 and A4 areas, A5 with m 3 as Mc, m 6 and p 6 as Mc, ‘s’ between m 6 and p 6, ‘ms’ interior; AbdIV without Mc on areas A6–A8, A9 with one Mc (A 5), A10 with one Mc (B 6); sensillar formula very similar to the Entomobryidae : 2,2/1,2,3,7,3, and long like-sensilla chaetae (long and smooth) all over the tergite AbdIV; microsensillar formula: 1,0/1,0,1.

3a2,

Remarks. Mari-Mutt (1980) wrote an exhaustive survey of the genus with nearly complete descriptions of the species. However, some important characters currently used for the identification were not considered at that moment. The dorsal macrochaetotaxy of specimens identified as H. nitidus from caves in Navarra ( Spain) and those from Caucasus appear to be identical except for small differences in the head. The subfamily Heteromurinae belongs to the family Orchesellidae owing only to the subdivision of the Ant I.

Figures

FIGURE 9. Heteromurus nitidus. A, head macrochaetotaxy; B,Th II–III dorsal macrochaetotaxy; C, AbdII–IV dorsal macrochaetotaxy (black spots, Mc; white triangles, sensilla; black triangles, microsensilla; squares, bothriotricha) (scale bar 0.05mm).

FIGURE 10. Heteromurus nitidus. A, dorsal body macrochaetotaxy; B, claw and empodium; C, scale; D, lateroventral area of distal AntIV; E, dorsal section on mid AbdIV; F, ventral section on mid AbdIV (scale bars: A, 0.05 mm; B–F, 0.025mm).