Protaphorura nikolai, Kaprus', Igor, Weiner, Wanda & Pasnik, Grzegorz, 2016

Kaprus', Igor, Weiner, Wanda & Pasnik, Grzegorz, 2016, Collembola of the genus Protaphorura Absolon, 1901 (Onychiuridae) in the Eastern Palearctic: morphology, distribution, identification key, ZooKeys 620, pp. 119-150 : 123-124

Taxon classification Animalia Collembola Onychiuridae

Protaphorura nikolai sp. n. Figs 18-25, 58

Type material.

Holotype (male): Russia, Primorsky Krai, Khasansky district, Barabash village, mixed forest with Quercus , Acer and Juglans , in soil and leave litter, 9.VII.2011, leg. N.A. Ryabinin (SNHM). Paratypes: 6 males and 6 females, same data as holotype (SNHM - 9 paratypes: 5 male and 4 females, ISEA - 3 paratypes: 1 male and 2 females).

Diagnosis.

PAO with 29-36 simple vesicles. Pso formula dorsally 33/022/33342, ventrally 1/000/0000, subcoxae 1 of I–III legs with 1,0,0 pso respectively. Submedial pso a and b on Abd. terga I–II located close together. Psx formula on Abd. sterna: 100000. Th. tergum I with 11 –12+11– 12 chaetae, chaeta m present. Chaetae s' absent on Abd. terga I–III and V. Manubrial field with 14-15 chaetae in 3 rows. Claw without lateral denticles.

Description.

Holotype (male) length 1.5 mm, length of paratypes: 1.45-1.55 mm (males) and 1.58-1.72 mm (females). Shape of body typical for the genus: cylindrical with strong AS on distinct papillae (Fig. 18). Colour in alcohol yellowish-white. Granulation more or less uniform, distinct. Usually 12-14 grains around each pso.

Antennae approximately as long as head, their base well marked. Ant. I with 11-12 chaetae, Ant. II with 17-18 chaetae. AIIIO consisting of 5 guard chaetae, 5 papillae, 2 smooth sensory rods, 2 straight and granulated sensory clubs, ventro-lateral microsensillum present (Fig. 19). Ant. IV with subapical organite in cavity protected by cuticular papillae (Fig. 20). Microsensillum on Ant. IV situated on level or below of second proximal row of chaetae. Ventrally Ant. IV with numerous chaetae (ca. 68-72). Ant. IV without differentiated sensilla (Fig. 19).

PAO is relatively small with 29-36 simple vesicles (Fig. 21). Labral formula of chaetae: 4/342. Maxillary outer lobe with simple palp, basal chaeta and with two sublobal hairs. Labial palp of type A. Labium with 7 proximal, 4 basomedian (E, F, G, and f), and 6 basolateral chaetae (a, b, c, d, e, e’). Papillae A-E with 1, 4, 0, 3, 3 guard chaetae respectively.

Pso formula dorsally 33/022/33342, ventrally 1/000/0000 (Figs 18, 22, 24). Subcoxae1 of legs I, II and III with 1,0,0 pso respectively. Psx on subcoxae1 of legs I, II and III absent. Submedial pso a and b on Abd. terga I–II located close together, i.e. much closer than on Abd. tergum III, both set posteriorly to macrochaeta p5 (Fig. 18). Ventral psx formula 1/000/100000). Psp formula dorsally 0/011/1111, ventrally 0/111/01m1m1m, coxae with 1 psp each.

Dorsal chaetotaxy slightly asymmerical, chaetae well differentiated into macrochaetae, mesochaetae and microchaetae as in Fig. 18. Sensory chaetae s indistinct on body. On head p2 chaetae on same level as p1 and p3. Chaetae p6 on head located anterior to pso b (Fig. 18). Th. tergum I with 11 –12+11– 12 chaetae, chaeta m present (chaetotaxy type i2-3m). Both Th. terga II and III with lateral microsensilla and with 4+4 or 5+5 axial microchaetae. Chaetae s' absent on Abd. terga I–III and V. On Abd. tergum IV in axial area between M2 and P2 macrochaetae located 9-11 chaetae, medial chaeta m0 present or absent, p0 present or absent (Fig. 18). Abd. tergum V usually with 1 unpaired microchaeta p0 (m0 absent) (Fig. 18). Abd. tergum VI with 1 medial chaetae m0. Relative position of prespinal microchaetae of distinctly divergent type (Fig. 25). M/s ratio on Abd. tergum V as 33 –40/20– 22, (AS = 10). AS 0.6-0.7 times as long as inner edge of claw and 2.0 times longer than their basal diameter.

Chaetotaxy of ventral side of head as in Fig. 22. Perilabial area with 4+4 a-chaetae. Postlabial chaetae 5+5 along ventral groove. Th. sterna I–III with 1+1, 2+2, 2+2 chaetae respectively. VT with ca. 8 –9+8– 9 chaetae, and 2(1)+2(1) chaetae at base. Chaetotaxy of Abd. sternum IV as in Fig. 22. Furcal rudiment: cuticular fold (located near the middle of sternum) with 2+2 dental microchaetae in 2 rows. Chaetotaxy of manubrial field: 4 chaetae present in ma-row, 6-7 chaetae in mm-row and 4 chaetae in mp-row (Fig. 24). MVO absent. Each lateral anal valves with a0, 2a1 and 2a2; upper anal valve with chaetae a0, 2a2, 2b1, 2b2, c0, 2c1 and 2c2 (as in Protaphorura jernika , Fig. 58).

Subcoxae 1 of I, II and III legs with 5-6, 6-7 and 5-6 chaetae respectively, subcoxae 2 with 1, 5, 5, coxae with 3, 11, 13, trochanters with 11, 11, 10, femora with 21, 21, 18, tibiotarsi with four rows of chaetae (distal whorl (A+T)+B+C): 11+8+4, 11+8+4, 11+8+4-5 chaetae respectively. Claw with very strong denticle in the 1/2 of inner edge of claw (Fig. 23). Empodial appendage 0,9-1,0 times as long as inner edge of claw, without basal lamella (Fig. 23).

Etymology.

The species is cordially dedicated to Russian oribatologist Dr. Nikolay Ryabinin, who collected the type material of new species in Primorsky Krai of Russia.

Discussion.

Protaphorura nikolai sp. n. belongs to the group of Protaphorura species with 1,0,0 pseudocelli on subcoxa 1 of I, II and III legs and 1+1 pso on head ventrally. Among Asiatic species this group includes Protaphorura zori (Martynova, 1975 in Martynova & Chelnokov, 1975)(although Martynova did not mention subcoxal pso, the examined by us type has 1,0,0 pso on subcoxae), Protaphorura brevispinata (Yosii, 1966), Protaphorura changbaiensis Sun, Zhang & Wu, 2013, Protaphorura mongolica (Martynova, 1975 in Martynova & Chelnokov, 1975), Protaphorura sakatoi (Yosii, 1966) and Protaphorura maoerensis Sun, Wu & Gao, 2013. Within this group, it shares dorsal pso formula with Protaphorura zori but differs from the latter by the presence of inner denticle on claw, the absence of chaeta a0 on Abd. tergum VI (in Protaphorura zori inner denticle absent and chaeta a0 present) and by arrangement of prespinal chaetae (placed divergently in Protaphorura nikolai and convergently in Protaphorura zori ). Perhaps there are other differences in the morphology of these two species, but Protaphorura zori is not well described and needs more detailed study.