Paravietnura insolita, Smolis, Adrian & Kuznetsova, Nataliya, 2018

Smolis, Adrian & Kuznetsova, Nataliya, 2018, Paravietnura gen. n., a new intriguing genus of Neanurini from the Caucasus (Collembola, Neanuridae, Neanurinae), ZooKeys 739, pp. 41-54 : 45-48

Paravietnura insolita sp. n. Figs 9-18, Table 4, 5, 6

Type material.

Holotype: male on slide, Russia, Caucasus, Northern Ossetia, North Ossetia Nature Reserve, surroundings of the village Tsey, Kalpersky ridge, southern slope, 2160 m alt., litter of rocky pine grass forest, 19.8.1977, leg. M. Rudakovsky, N. Kuznetsova (MSPU). Paratype: male on slide, ibid., green moss pine forest, in mosses, 23.9.1980, leg. I. Kuchiev (DIBEC).

Etymology.

Its name reflects a later discovery of another species within the genus (Latin word " insolita " means not lonely).

Diagnosis.

Body relatively short and squarish. Macrochaetae long, relatively thin and narrowly sheathed. Buccal cone rather short, labrum non ogival. Labrum with four prelabral chaetae. Tubercle (Af +2Oc) on head with chaetae A, B, Ocm and Ocp. Tubercles (Dl+L+So) on head with eleven chaetae, chaetae So2 present. Furca rudimentary with well visible microchaetae, with chaetopores.

Description.

General. Body length (without antennae): 1.10 (paratype) to 1.35 mm (holotype). Colour of the body bluish. 2+2 black eyes of medium size (Fig. 9).

Chaetal morphology. Dorsal ordinary chaetae of four types: long macrochaetae (Ml), short macrochaetae (Mc), very short macrochaetae (Mcc) and mesochaetae. Long macrochaetae of medium length (longer than length of segment), relatively thin, slightly arc-like or straight, narrowly sheathed, strongly serrated and apically rounded (Figs 9, 12, 14, 16). Macrochaetae Mc and Mcc morphologically similar to long macrochaetae, but much shorter. Mesochaetae similar to ventral chaetae, thin, smooth, and pointed. S–chaetae of tergites thin, smooth, and markedly short, three or four times shorter than nearby macrochaetae (Figs 12, 15).

Antennae. Dorsal chaetotaxy of Ant. III–IV as Fig. 10 and Table 5. S–chaetae of Ant. IV long and moderately thickened, S4 and S7 slightly longer than others (Fig. 10). Apical vesicle distinct bilobed. Ventral chaetotaxy of Ant. III as Fig. 11 and Table 5, sensillum sgv notably elongate and s-shaped.

Mouthparts. Buccal cone short with labral sclerifications non-ogival (Fig. 17). Labrum chaetotaxy: 4/2, 4. Labium with three basal, three distal and three lateral chaetae, papillae x absent (Fig. 18). Maxilla styliform, mandible thin and tridentate.

Dorsal chaetotaxy and tubercles. Chaetotaxy of head as Fig. 9 and Table 4. Chaetotaxy of Th. and Abd. as Table 6. Thorax and abdomen with chaetae De2 and De3 not free. On Abd. I–III, the line of chaetae De1-chaeta s perpendicular to the dorsomedian line. On Abd. IV chaetae Di1 longer than on Abd. V (Figs 14, 16). On Abd. V chaetae Di2 present and Di3 absent (Fig. 12). Cryptopygy present, well developed.

Ventral chaetotaxy. On head, groups Vea, Vem and Vep with 3, 2, 4 chaetae respectively. Group Vi on head with six chaetae. On Abd. IV, furca rudimentary with clearly visible microchaetae, each with chaetopore (Fig. 13). On Abd. IV, tubercle L with five chaetae. On Abd. V, chaetae L’ present.

Legs. Chaetotaxy of legs as in Table 6. Claw without internal tooth. On tibiotarsi, chaeta M present and chaetae B4 and B5 relatively short and pointed.

Remarks.

Paravietnura insolita sp. n. can be confused with the only other described species in the genus Paravietnura notabilis sp. n., which has thick and widely sheathed long macrochaetae (distinctly thinner and narrowly sheathed in insolita ), an ogival labrum (non-ogival in insolita ), chaetae A and So2 reduced on the head (present in insolita ), chaetae L’ reduced on Abd. V (present in insolita ), and the furca rudimentary with minute microchaetae without chaetopores (longer microchaetae with distinct chaetopores in insolita ).

Ecological note.

Similarly to the previous species, Paravietnura insolita sp. n. seems to be very local and connected with specific climatic and vegetation conditions, probably with mountain xeric pine forest.

Variabilty.

We observed an asymmetrical absence of chaeta A in the holotype (Fig. 9).