Supraphorura chernovae, Gulgenova & Potapov, 2023

Gulgenova, Ayuna & Potapov, Mikhail, 2023, Two new species of Onychiuridae (Collembola) from East Siberia (Russia), Zootaxa 5336 (1), pp. 125-134 : 126-128

Supraphorura chernovae sp. nov.

Figs 1–10

Type material. Holotype: male, Russia, East Siberia, SW Buryatia, southern macroslope of Malyi Khamar-Daban Range, near Burguy 50°27.25′N, 103°46.8′E, 1049 m. alt., cedar-larch forb forest, in litter and soil, 30 September 2014. B. Dugarova leg. Paratype: male, at the same locality, litter and soil of green moss-shrub birch-larch forest, 21 July 2014. B. Dugarova leg.

Additional material. Immature female, same region, southern macroslope of Malyi Khamar-Daban Range, near Burguy, cedar-larch forb forest, 30 September 2014. B. Dugarova leg.; 2 juveniles, at the same locality, litter of green moss-shrub birch-larch forest, 30 September 2014. B. Dugarova leg.

Diagnosis. Pseudocellar formulae as 32/022/23232 dorsally and 1/000/00000 ventrally. Subcoxa 1 of all legs with 1 pso. Formula of psx ventrally: 0/000/11010. Abd. 1–3 and 5 without chaetae s’. Abd. 5 with chaetae a0, m0 (also absent) and p0, Abd. 6 with one medial chaeta. AS present. Claws with denticle. Empodial appendage without basal lamella, as long as the inner edge of the claw. Th. 1, 2, 3 with 0+0; 1+1; 1+1 ventral chaetae, respectively. Ventral tube with 9+9 chaetae and 2+2 chaetae at its base. MVO absent.

Description. Holotype (male) length 1.8 mm. Colour in alcohol white. Granulation more or less uniform, distinct. Body shape thickened in the posterior half, with strong anal spines on distinct papillae ( Fig. 1 ). Antennae approximately as long as the head. Ant. 1 with 11 chaetae ( Fig. 2 ). Ant. 4 with the subapical organite ( Fig 3 ). Microsensillum on Ant. 4 in latero-external position, ca 1/3 the length from the base. Ant. 3 microsensillum slightly below the AIIIO.AIIIO with 5 guard chaetae, 5 papillae, 2 granulate sensory clubs and 2 sense rods ( Fig. 5 ). Labrum with 9 chaetae and 4 prelabrals. Labium of type A, with 7 guard chaetae ( Fig. 4 ). Proximal field with 7 chaetae. Basal fields with 4 basomedial + 6 basolateral chaetae. Mandibles and maxilla unmodified. Maxillary palp simple, with 2 sublobal hairs. PAO with about 30 simple vesicles arranged in 2 rows along the long axis of the organ ( Fig 6 ).

Pso formula dorsally 32/022/23232 (one adult specimen lacking the median pair of pso on Th. 3, with the pso formula of thorax as /021/) ( Fig. 1 ). Median pair of pso absent on Abd. 3. Pso formula ventrally: 1/000/00000. Subcoxa 1 of all legs with 1 pso each. Formula of psx ventrally: 0/000/11010, all subcoxa 1 and femora with 1 psx each.

Dorsal chaetotaxy well differentiated into macro- and microchaetae ( Fig. 1 ). Th. 2–3 with 1 microsensillum laterally, each. Head without chaeta d0. Abd. 5 without chaeta s’. Abd. 1–4 s’-chaetae difficult to determine. Abd. 5 with chaetae a0, m0 (also absent) and p0, Abd. 6 with one medial chaeta. Abd. 6 with a characteristic transverse row of 6 anterior chaetae, anal spines slender, curved, slightly shorter than inner edge of claws. Head with 5–6 ventral chaetae on each side of the mid-line. Th. 1, 2, 3 with 0+0; 1+1; 1+1 ventral chaetae, respectively. Ventral tube with 9+9 chaetae and 2+2 chaetae at its base, respectively ( Fig. 10 ). Furca present, dens with 3 chaetae and a pointed blunt-tipped mucro. Retinaculum with 2+2 teeth ( Figs 7, 8 ).

Claws with denticle. Empodial appendage without the basal lamella, as long as the inner edge of the claw, with a filament ( Fig. 9 ). Tibiotarsi with a complete chaetotaxy, with 23 chaetae: (C: 4, B+M: 8, A+T: 11), chaeta M and all four T-chaetae present. MVO absent.

Etymology. It is a pleasure to dedicate the species to our master Dr. Nina Chernova , in appreciation for her significant contribution to the ecology of Collembola.

Distribution and ecology. The species is only known from one locality in Malyi Khamar-Daban Range (SW Buryatia), and it inhabits different types of larch forests. It is possible that the new species is relatively rare because only 5 specimens were found in 90 samples taken.

Affinities. According to Bellinger et al. (1996 –2023), the genus Supraphorura includes one single species, Supraphorura furcifera ( Börner, 1901) , which was redescribed by Pomorski (1998) and Fjellberg (1998) in detail. Supraphorura chernovae sp. nov. differs from S. furcifera by the number of pseudocelli on Th. 2 (2 vs. 1) and Abd. 5 (2 vs. 3), which results in distinct pseudocellar formulae (32/022/ 23232 in the new species vs. 32/012/23233(2)). The new species also has 1 pso on all subcoxa 1 (absent in S. furcifera ) and 30 vesicles in the PAO (vs. 20).

Figures

FIGURES 1–6. Supraphorura chernovae sp. nov.: 1, head and body dorsal chaetotaxy and pso distribution; 2, dorsal and ventral sides of antenna, respectively; 3, apical region of Ant. IV; 4, labial palp; 5, sensorial elements of AIIIO; 6, PAO and adjacent pso.

FIGURES 7–10. Supraphorura chernovae sp. nov.: 7, chaetotaxy and distribution of pso on the ventral side of Abd. 3–6; 8, remnant of furca; 9, claw and tibiotarsus of leg. 2; 10, ventral tube (ventral view).