Entomobrya nigrocincta Denis, 1923

Baquero, Enrique & Jordana, Rafael, 2018, Entomobrya (Collembola, Entomobryidae) for the Canary Islands, Zootaxa 4461 (2), pp. 151-195 : 186-188

Entomobrya nigrocincta Denis, 1923

Figs 3 FG–G’, 4O–O’, 18A–G

Material studied. All A. Fjellberg leg.: Gran Canaria, Barr. Oscuro (Barr. de Virgen), moss on rocks, dry

laurisilva, 8.I.1988, 27A/88–1, coordinates 28.06685°N, 15.59191°W, 750 m a.s.l., (Loc. 51) one male on slide (MZLU-VAR00001734); Tenerife, Icod de los vinos, litter under palms, garden, 8.IV.1972, coordinates 28.37011°N, 16.71443°W, 235 m a.s.l., (Loc. 18) one female on slide (MZLU-VAR00001736), one male on slide (MZLU-VAR00001737) and two males and five females in ethyl alcohol (MZLU-VAR00001738 to MZLU- VAR00001744); Tenerife, Las Arenas, moist grass on trail, 14.IV.1972, coordinates 28.39253°N, 16.54783°W, 230 m a.s.l., (Loc. 24) one male on slide (MZLU-VAR00001746) and one specimen in ethyl alcohol (MZLU- AR00001747). Lanzarote, Masdache (Teguise-Uga), vegetation, rock fissures, 21.I.1988, 97/88–1, coordinates 28.99642°N, 13.66289°W, 360 m a.s.l., (Loc. 59) one male in ethyl alcohol (MZLU-VAR00001735).

Description of the studied specimens from the Canary Islands. Body length mean of 1.55 mm, excluding antennae (n = 4). Species with sexual dimorphism in colouration: female, general pattern very similar to the species E. multifasciata , with which it is easily confused; ground colour white, with narrow transverse bands on posterior Th II to Abd III but leaving a dorsolateral area without pigment, two transversal irregular bands on Abd IV, and dorsal Abd V and VI with a large central patch; legs only with a distal small patch on femur; antennae with distal or half distal area pigmented, Ant IV totally pigmented; male, ground colour pale yellow, with dark pigment exclusively on anterior and posterior Th II (not lateral) and the totality of the tergites Th III and Abd I; legs with more pigment than the female; male and female with a lateral band on the head, from anterior area to eyes and posterior eyes ( Figs 3F , 4O ).

Head. Eight eyes, GH smaller than EF. Antennae length 0.67 mm, 2.44 times the length of the head (n = 4 for all measurements). Ant IV with apical vesicle bilobed. The relative length of Ant I/II/III/IV = 1/1.85/1.68/2.19. Prelabral chaetae ciliated. Labral papillae multispinose ( Fig. 18E ). Lateral process of labial papilla E reaching the papilla end.

Body. Length ratio of Abd IV/III = 3.56 to 4.70 (n = 4). Trochanteral organ with variable between 10–20 chaetae. Tibiotarsus not sub-segmented, without smooth chaetae, except for smooth terminal chaeta on legs III. Claw with four teeth: paired at 50% and first unpaired at 75% from basis; dorsal teeth not basal ( Fig. 18F ). Empodium lanceolate, with serrated external lamella in leg III. Tenent hair clavate. Length of manubrium and dens 0.23 and 0.29 mm, respectively (n = 4). Manubrial plate with four chaetae and two pseudopores. Mucro with teeth similar in size, mucronal spine reaching the tip of the subapical tooth ( Fig. 18G ).

Macrochaetotaxy ( Figs 18A–D ). Simplified Mc formula: 3-1-0-2-2/2-3/1-2/1-1-1/0-2-3-2-2. Head: in addition to the information of the formula, S4 on H4 present in one specimen. Mesothorax: area T1 with two Mc (m1 and m 2i); T2 with three Mc (m4, m 4i and a5). Abdomen: Abd II area A1 with one Mc (a 3 in one specimen as mesochaeta), area A2 with two Mc (m3 and m3e); Abd III with one Mc each on areas A3 (a1), A4 (a2) and A5 (m3e); Abd IV with two Mc on A7 (A4 and B4; sometimes lack one of them), two Mc on A8 (A4, B4 and C2a), and two Mc on A9 (A5 and B5) and A10 (A6 and B6).

Ecology. Found in Gran Canaria (moss on a rock, dry laurisilva), Lanzarote (rock fissures) and Tenerife (litter under palms in a garden and on moist grass).

Remarks. A small difference with the specimens of other parts of the world is observed: the presence of an additional mesochaeta (a3) on the Abd II area A1. Following the remark for E. atrocincta (pag. 102) and E. nigrocincta (p. 153) in Jordana (2012) it is explained that there is confusion between the denomination of E. atrocincta and E. nigrocincta since the book of Salmon (1944), which subsequent authors have followed. Katz et al. (2015b) already referred to this problem but for the American population, in which they find colour and chaetotaxy variations. In future studies, the similarity of the American, European and Australian species should be studied, including DNA analysis. The chaetotaxy and the male’s colour separate this species from other species of the world.

Figures

FIGURE 3. Entomobrya habitus: A, E. guayarminae sp. nov.; B, E. icoae sp. nov. (at left AbdII–IV with a darker pattern); C– D’, E. irayae sp. nov. C, clear form, D–D’ dark form; D’’ E. naziridisi; E, E. multifasciata (E’ dark form); F, E. nairae sp. nov.; F’ E. nevadensis; G, E. nigrocincta, male (G’ female); H, E. palmensis; I, E. cf. quiquelineata; J, E. unostrigata. Bar = 0.5 mm.

FIGURE 4. Entomobrya colouration pattern: A, E. achuteygai sp. nov.; B, E. airami sp. nov.; C, E. amelahuigei sp. nov. (C’. E. amelahuigei sp. nov., dark form); D, E. atteneri sp. nov.; E, E. nairae sp. nov.; F, E. atteneri sp. nov. (clear form); G; E. fainae sp. nov. (G’, E. fainae sp. nov., dark form); H, E. gazmirae sp. nov.; I, E. grimanesae sp. nov. (I’, E. grimanesae sp. nov., dark form); J, E. guacimarae sp. nov. (J’, intermediate colour form; J’’, pale form); K, E. guayarminae sp. nov.; L, E. icoae sp. nov.; M, E. irayae sp. nov.; N, E. multifasciata; O, E. nigrocincta male (O’, female); P, E. palmensis; Q, E. cf. quinquelineata; R, E. irayae sp. nov. dark form; S, E. unostrigata. Bar = 0.5 mm.

FIGURE 18. E. nigrocincta: A, head chaetotaxy; B, Th II chaetotaxy; C, Abd II–III chaetotaxy; D, Abd IV chaetotaxy; E, labral papillae; F, claw and empodium of leg III; G, tip of dens and mucro (bar for F and G = 0.025 mm, F = 0.010 mm).