Onychiuroides mazandaranensis Arbea, Yahyapour & Shayanmehr, 2020

Yahyapour, Eliye, Shayanmehr, Masoumeh, Vafaei-Shoushtari, Reza & Arbea, Javier I., 2020, A review of the Iranian species of the family Onychiuridae (Collembola Poduromorpha), with description of five new species from Hyrcanian Forests in Iran, Zootaxa 4861 (1), pp. 1-22 : 9-10

Onychiuroides mazandaranensis Arbea, Yahyapour & Shayanmehr sp. nov.

Figs 22–33 , Table 3

Type locality. Iran, Mazandaran Province, Sari county, Salardare forest , 28 m a.s.l. (36º32ʹ59ʺ N, 53º7ʹ31ʺ E) .

Type material. Holotype female, Mazandaran Province, Sari county, Salardare forest , soil and leaf litter, 29 April 2016, leg. Eliye Yahyapour. Paratypes: All specimens from the same locality as holotype, 1 female, 2 males and 8 juveniles . Holotype and 1 paratype male deposited in MNCN, 10 paratypes in SANRU .

Other material: Iran, Mazandaran Province, Tonekabon county, Dohezar forest , 443 m a.s.l. (36º40ʹ21.7ʺ N, 50º49ʹ28.5ʺ E), soil and leaf litter, leg. Eliye Yahyapour, 10 November 2016, 1 juvenile. Deposited in SANRU .

Etymology. The species was named after the type locality, Mazandaran province.

Description. Holotype (female) length without antennae 0.9 mm, paratypes: males length 0.8–0.9 mm; females length 0.7–0.9 mm. Body cylindrical, distinctly broadened in the region of Abd. III–IV. Without AS ( Figs 22 and 23 ). Color in alcohol, white. Cuticular granulation on dorsal surface of the body more or less uniform, distinct.

Antennae shorter than head (ratio 0.75–0.85). Antennal base well marked. Ant. I–III with 10, 18, 15 chaetae, respectively. AIIIO with 5 guard chaetae, 4 papillae, 2 smooth sensory rods, 2 granulated sensory clubs, ventro-lateral ms present ( Fig. 30 ). Ant. IV with subapical organite, and latero-external ms, ca. 0.25 length from the base; with some blunt macrochaetae and thin mesochaetae-like sensilla, not well distinguishable from ordinary chaetae.

PAO with 9–11 compound vesicles disposed in two parallel rows ( Fig. 27 ). Labral formula of chaetae: 4/342 ( Fig. 31 ). Maxillary outer lobe with simple palp, basal chaeta and with 2 sublobal hairs. Labium with 6 proximal, 4 basomedian (E, F, G, and f), and 5 basolateral chaetae ( Fig. 32 ). Labial palp of A type; labial papillae A, B, C, D, E with 1, 4, 0, 3, 3 guard chaetae respectively.

Pso formula dorsally: 22/133/33332; ventrally: 1/000/1212. Pso arranged as in Figs 22–24 . Subcoxae 1 of I–III legs with 2, 2, 2 pso. Psx and psp not seen.

Dorsal chaetotaxy symmetrical, well differentiated into apically rounded macro- and mesochaetae and apically pointed microchaetae. Sensilla on body indistinct. Chaeta d0 on head present. Th. I with 5–6+5–6 chaetae. Th II. and III with lateral ms. Chaeta p0 present on Abd. IV. Chaeta m0 often present on Abd. IV and V; Abd. VI without unpaired chaetae ( Fig. 25 ).

Ventral chaetotaxy as in Fig. 24 . Without chaetae between legs on pro-, meso- and metasternum. VT with 6+6 chaetae, and 2 basal chaetae laterally. Furca reduced to small depression with finer granulation, in contact with bor- der between Abd. III and IV sternites, with two small posterior chaetae accompanied by 1+1 lateral, larger chaetae, three irregular manubrial rows: ma-row with 1–2+2 chaetae, mm-row with 2+2, mp-row with 2+2–3 chaetae (external ones as macrochaetae) ( Figs 26 , 28, 29 ). Without male ventral organ. Anal valves with numerous acuminate chaetae; each lateral valve with chaetae a0, 2a1; unpaired anal valve with chaetae a0, 2a1, 2b1, 2b2, c0, 2c1, 2c2.

Legs: Subcoxae 1 of I–III legs with 4–5, 5, 5 chaetae, subcoxae 2 with 1, 3, 4, coxae with 2, 8–12, 13, trochanters with 10–11, 9–11, 9–11, femora with 17, 19–20, 19–20, tibiotarsi of legs I–III with 21–22(11+8+2–3), 21(11+8+2), 20(11+7+2) chaetae, respectively. Claw without denticle. Empodial appendage without basal lamella, distinctly shorter than claw ( Fig. 33 ).

Discussion. According to Pomorski (2006), Onychiuroides mazandaranensis sp. nov. belongs to the group of species with 4 papillae and 5 chaetae in AIIIO. Within this group it is characterized by the dorsal pso formula (22/133/ 33332 in the new species vs 33/133/ 33333 in other species). The main diagnostic characters of these species are summarized in Table 3 . By the dorsal pso formula the new species is similar to O. paucituberculatus ( Stach, 1930) (32/122/33332 dorsal pso) and O. longisetosus ( Stach, 1954) (12/133/33332 dorsal pso), but both species need redescription (Pomorski 2006).

Figures

FIGURES 22–27. Onychiuroides mazandaranensis sp. nov.: 22, head and Th. dorsal chaetotaxy; 23, Abd. dorsal chaetotaxy; 24, Abd. ventral chaetotaxy of a female; 25, Abd. V and VI dorsal chaetotaxy; 26, furcal area; 27, PAO. Scales: 0.2 mm (22–24), 0.03 mm (25–27).

FIGURES 28–33. Onychiuroides mazandaranensis sp. nov.: 28–29, furcal area; 30, AIIIO and ms on Ant. IV; 31, labrum; 32, labium (chaetae of labial papillae not represented); 33, tibiotarsus and claw III. Scales: 0.02 mm.