Oligaphorura tatianae, Shveenkova & Babenko, 2022

Shveenkova, Yulia B. & Babenko, Anatoly B., 2022, Three new Oligaphorura species (Collembola: Onychiuridae) of the marcuzzii-group from the Caucasus, Zootaxa 5116 (4), pp. 579-590 : 583-586

Oligaphorura tatianae sp. nov.

Figs 1–2 , 15–16 , 19–22 ; Table 1

Type material. Russia: holotype, male, North Caucasus , Karachay-Cherkess Republic , Teberda State Nature Reserve, Goralykol River gorge [43.4514°N, 41.8236°E], pine forest with green mosses and Calamagrostis sp. , ~ 1800 m alt., soil and litter, 15.06.2016, N. Kuznetsova & A. Geraskina leg. Paratypes: 2 males, 1 juvenile, same data as holotype; 1 female, same Nature Reserve , Teberda River valley, road to Baduk lakes [43.6425°N, 41.885°E], 1380 m alt., spruce forest, litter, 25.06.2015, N. Kuznetsova & A. Geraskina leg. The types are kept in the MSPU collection.

Diagnosis. Body cylindrical. Dorsal sensilla on body well-marked. Anal spines absent. Number of pso: 43/133/44(5)364 (dorsal), 11/000/1112 (ventral), 222 (subcoxal). Ventral psx hardly visible. AIIIO with 5 papillae, PAO slightly larger than nearest pso, with 3–4 lobes. Labium of ABD-type (papillae C and E lower, each with a short terminal sensillum). Th. III without lateral ms. Abd. IV with an unpaired seta p0. Tibiotarsal chaetotaxy complete, distal whorls (A+T) of each Ti with 11 setae. Furcal remnant of schoetti - type, with a small cuticular fold.

Description. Size 0.55–0.66 mm, holotype 0.63 mm. Colour white in alcohol. Body cylindrical. Granulation regular, slightly coarser around dorsal pso (10–12 granules) ( Fig. 19 ).

Number of pso: 43/133/44(5)364 (dorsal) and 11/000/1112 (ventral) ( Figs 19–21 ). Ventral psx almost invisible, although in one specimen psx asymmetrically present on Abd. II ( Fig. 20 ). Each upper Sc of legs I– III with 2 pso .

Antennae slightly shorter than head. Ant. IV with 3 poorly thickened S-setae, subapical organite present, microsensillum located in proximal row of setae ( Fig. 16 ). AIIIO on Ant. III consisting of 5 papillae, 5 guard setae, 2 sensory rods, 2 granulated clubs (external one larger) and lateral ms. Ant. I–II with 9 and 14 setae, respectively. Antennal area slightly marked. PAO located laterally in a cuticular furrow, with 4(3) lobes, slightly larger than nearest pso. Maxilla unmodified. Maxillary palp simple with 1 basal seta and 2 sublobals. Labrum with 4/342 setae. Labial palp with 11 (4 spiniform and 7 longer ones) guards and 5 proximal setae. The exact assignment of longer guards problematic: four of them located around papilla E and three others—next to papillae B and D. Basomedian and basolateral fields of labium with 4 and 5 setae, respectively. Terminal sensilla of papillae A, B and D thickened, papillae C and E lower, both with very short terminal sensilla (labium of ABD type) ( Fig. 22 ).

Dorsal setae poorly differentiated into macro—and microsetae, symmetrical in general ( Fig. 19 ). S-setae well marked and distributed as follows: 11/022/22211 (dorsally), 11/000/000101 (ventrally) and 0, 0, 1 on lower Sc of legs I–III. Head with an axial unpaired seta a0 but without a0’, d0 absent as usual for the genus. Setae p1 on head at level with p2. Th. I with 5+5 dorsal setae. Lateral ms present only on Th. II and absent on Th. III. Terga of Th. II–Abd. III each with 3–4 pairs of axial setae. Abd. IV with an unpaired seta p0. On Abd. VI, setae a0 and a2 approximately same in size, setae a1 half as long as a0. Thoracic sterna with 0-1-1 setae each side of ventral line. Ventral chaetotaxy as in Figs 20–21 .

Upper subcoxae of legs I–III with 4, 5, 5 setae, respectively. Tibiotarsal chaetotaxy complete with 20–21–19 setae, respectively: distal whorls (T+A) with 11 setae, 7 B-setae (B7 absent only on Ti III), one seta (or two setae on the second leg) of C-whorl and an unpaired seta M. Unguis with neither inner nor lateral teeth, unguiculus narrow, with a narrow basal lamella, about half as long as inner edge of unguis ( Fig. 15 ). VT with 6+6 proximal setae and 2+2 setae at base. Furcal remnant of schoetti - type, cuticular fold small, sometimes indistinct ( Figs 1–2 , 20 ). Each lateral anal valve with a0, 2a1 and 1а2 setae, unpaired valve with a0, 2b1, 2b2 and 7 setae in c-row (b0 and a1 absent). Anal spines absent.

Etymology. The species honours Tatiana Dobrolyubova who worked for a long time in the Teberda Nature Reserve, and whose ecological papers formed the basis for the study of Collembola in the North Caucasus.

Affinities. Among the representatives of the marcuzzii -group, O. tatianae sp. nov. is obviously most similar to O. montivaga sp. nov., the latter from a more easterly part of the North Caucasus. Apart from more or less stable differences in the number of dorsal pso (43/133/44(5) 364 in O. tatianae sp. nov., vs 43/144/ 44354 in O. montivaga sp. nov.), these species clearly differ in the fine structure of the labium (papilla E present in O. tatianae sp. nov., vs absent from O. montivaga sp. nov.). The presence of papilla E on the labial palp in O. tatianae sp. nov. is a unique trait that makes the species distinguishable from all other known forms with the ABD-type of the labium, viz. O. montivaga sp. nov., O. kremenitsai , O. humicola and O. igori sp. nov. (see below). Other differences with the known congeners of the group are shown in Table 1 .

Figures

FIGURES 1–8. Types of furcal area in Oligaphorura species. 1–5, S or schoetti-type: 1–2, two different interpretations, Oligaphorura tatianae sp. nov.; 3, Oligaphorura montivaga sp. nov.; 4, Oligaphorura igori sp. nov.; 5, O. psammophila Shveenkova & Babenko, 2021; 6, A or absoloni-type, O. jiguliensis Shveenkova & Babenko, 2021; 7, H or humicola-type, O. kremenitsai; 8, D or differens-type, O. imosolica Shveenkova & Babenko, 2021.

FIGURES 13–18. Oligaphorura montivaga sp. nov. (13–14), Oligaphorura tatianae sp. nov. (15–16), Oligaphorura igori sp. nov. (17–18): 13, antenna, different views; 14, tip of leg II; 15, tip of leg I; 16, antenna, different views; 17, antenna, different views; 18, tip of leg I. Scales. Figs 13, 16, 17: 0.05 mm; 14, 15, 18: 0.025 mm.

FIGURES 19–22. Oligaphorura tatianae sp. nov.: 19, dorsal chaetotaxy; 20, ventral chaetotaxy of abdomen; 21, ventral chaetotaxy of head; 22, labial palp with basomedian and basolateral parts of labium (spiniform guards not shown). Scales. Figs 19–21: 0.05 mm; 22: 0.025 mm.