Philotella aliniensis, Babenko & Shveenkova & Potapov, 2022

Babenko, Anatoly, Shveenkova, Yulia & Potapov, Mikhail, 2022, New species of the genus Philotella Najt & Weiner, 1985 (Collembola, Neanuridae, Pseudachorutinae) from the Russian Far East, Zootaxa 5174 (5), pp. 525-550 : 536

Philotella aliniensis sp. nov.

Figs 22–24

Type material. Holotype: female, Southern Primorye , Sikhote-Alin State Nature Reserve ( Fig. 1 , point 9), coniferous forest with Rhododendron brachycarpum , 45°8.30’N 135°53.22’E, ~ 930 m alt., litter, 08 August 2017. N. Kuznetsova, A. Kuprin & A. Geraskina leg. Paratypes: 1 female and 7 juveniles, same biotope; 1 immature female, same region, ~ 30 km SE of Chuguevka ( Fig. 1 , point 7), mixed forest, 44°1.32’N 134°9.02’E, ~ 500 m alt., 11 August 2017. N. Kuznetsova, A. Kuprin & A. Geraskina leg.

Diagnosis. A species of the genus Philotella characterized by the presence of (2)3+3 ocelli, coarse granulation, the second row of labral setae with two longer and three shorter setae; a labium of the second type, dorsal chaetotaxy with p2 present on Th. II –III but absent on Abd. I – V; three ordinary setae (a3, a4 and m4) in dorsolateral group on Th. II –III and two setae (a3 and p3) between axial group and sensilla p4 on Abd. I – III; a complete tibiotarsal chaetotaxy and toothless unguis .

Description. Length (without antennae) up to 0.53 mm. Habitus typical of the genus. Alive colour unknown, probably rather dark. Tegument granulation very strong, especially on head and abdominal tip, but fields with larger granules also present on most terga.

Antennae clearly shorter than head, Ant. III–IV fused dorsally. Ant. IV with simple or slightly divided apical vesicle; external ms, subapical or and seta i present; six sensilla (S1–S4, S7–S8) on dorsal side of Ant. IV clearly differentiated, blunt and elongate; few sensilliform setae of various shape also present on its ventral side. Antennal organ of Ant. III typical, inner sensilla small, sgv longer than sgd and curved, ventral ms present. Ant. I–II with 7 and (11)12 setae, respectively.

Head with (2)3+3 [?] hardly visible ocelli, about as large as surrounding secondary granules on ocular field ( Fig. 23 ). PAO rounded, consisting of 10–12 vesicles, its axis to ocellus B ratio as 2.1–2.6: 1. Buccal cone short and blunt. Maxilla styliform, lamellae not clearly seen. Mandible delicate, with five teeth, two of which tiny and hardly detected. Labrum with a common set of 4/2352 setae of different length, the second row with two longer marginal setae and three smaller median ones (cf. Fig. 17 ). Main part of labium of the second type with three ordinary setae set in a triangular arrangement and 1+1 axial setae between sensorial elements ( Fig. 22 ); submentum and mentum with usual set of four setae each. Head ventrally with 2+2 postlabial setae.

Dorsal chaetotaxy almost symmetrical ( Fig. 24 ). Ordinary setae short, needle-like, sensilla longer, their number as usual: 22/11111, Th. II with lateral ms present as usual. Main characteristics: head usually with unpaired seta d0, ocular field with 3 setae; Th. I with 3+3 setae; Th. II–III with 3+3 axial setae (p2 present); dorsolateral group consisting of 3 ordinary setae (a3, a4 and m4) additionally to sensillum p 3 in backward position; Abd. I–III with 2+2 axial setae (p2 absent) and two setae (a3 and p3) between axial group and sensilla, both Abd. IV–V with 2+2 setae between sensilla.

Thoracic sterna without setae. Ventral tube with 4+4 setae, no seta on sternum of Abd. I, ventral side of Abd. II–III without unpaired axial setae. Furcal remnant in a form of two swellings, each with a seta, on anterior border of Abd. IV. Unpaired anal valve with three hr-setae, their number on paired valve variable (2–3).

Legs 1–3 with 1, 2, 2 setae on upper subcoxae, 0, 2, 2 setae on lower subcoxae, 3, 6, 6 setae on coxae, 6, 6, (5)6 on trochanters, and 13, 12, 11 setae on femora. Tibiotarsi with most complete set of setae: 19, 19, 18, seta M present. Unguis toothless.

Etymology. The new species is named after the region of its type locality, the Sikhote-Alin Mountains, based on the Manchu word “Alin” meaning mountain range.

Affinities. The dorsal chaetotaxy of P. aliniensis sp. nov. is almost identical to that of P. miracli : the only noticeable differences in this character lies in the presence of two setae between the axial group and sensilla on Abd. I–III in P. aliniensis sp. nov., whereas only a3 is present in this position in P. miracli . However, the very coarse granulation of the integument, the reduced number of ocelli, and the complete chaetotaxy of the tibiotarsi, all characteristic of the new species, make it fairly easily distinguished among these two species.

Figures

FIGURE 1. Map of main sampling plots. 1, Amur Region, Zeya State Nature Reserve; 2, Amur Region, Arkhara; 3, Southern Primorye, «Kedrovaya Pad» State Nature Reserve; 4, Southern Primorye, Ussuri State Nature Reserve; 5, Southern Primorye, Anisimovka, Mount Khualaza; 6, Southern Primorye, Mount Olkhovaya; 7, Southern Primorye, Chuguevka; 8, Southern Pri- morye, Mount Oblachnaya; 9, Southern Primorye, Sikhote-Alin State Nature Reserve; 10, Khabarovsk Territory, Ko Mountains; 11, Khabarovsk Territory, “Arseniev’s granites” Mts. Range; 12, Khabarovsk Territory, Komsomolsk State Nature Reserve; 13, Khabarovsk Territory, Tormasu River; 14, Khabarovsk Territory, Anyuinski National Park.

FIGURES 17–24. Philotella cedrina sp. nov. (17–21) & Philotella aliniensis sp. nov. (22–24): 17; labrum; 18, labium; 19, dorsal chaetotaxy; 20, Abd. V–VI (ventral); 21, lateral sensilla on Th. II–III, sensilla of Abd. III–V (top down); 22, labium; 23, ocular field and PAO; 24, dorsal chaetotaxy. Scales. Figs 19, 24: 0.1 mm; 17–18, 20–23: 0.01 mm.