Endonura cochlearifera, Smolis & Kuznetsova & Paśnik, 2024

Smolis, Adrian, Kuznetsova, Nataliya & Pasnik, Grzegorz, 2024, Phylogenetic analysis of Endonura Cassagnau, 1979 (Collembola, Neanuridae, Neanurinae), including descriptions of four new species, Arthropod Systematics & amp; Phylogeny 82, pp. 343-367 : 343

Endonura cochlearifera sp. nov.

Figs 16-25, Tables 5a-c, 6

Type material.

Holotype: adult female on slide, Russia, Caucasus, Northern Ossetia, North Ossetia Nature Reserve, surroundings of the village Tsey, green moss pine forest, in mosses, 23.IX.1980, leg. I. Kuchiev (DIBEC). Paratypes: 4 adult females, subadult male and 2 juveniles on slides, same data as holotype (DIBEC and MSPU).

Diagnosis.

2+2 pigmented eyes. Buccal cone long, labrum ogival. Head with chaetae A, B, C, D, E and O. Tubercles Cl and Af separate. Tubercles Dl and (L+So) on head with 6 and 9 chaetae respectively. Tuberles Di on Th. I absent. Tubercles De on Th. II and III with 3 and 4 chaetae respectively. Tubercles L on Abd. III and IV with 4 and 6-7 chaetae respectively. Abd. IV and V with 8 and 3 tubercles respectively. Claw without inner tooth. Tibiotarsi with chaetae B4 and B5 short.

Description.

Body length: 0.55 (juvenile) to 1.45 mm (without antennae) (holotype: 1.45 mm). - Colour: body pale bluish grey (alive and in alcohol). 2+2 black eyes, in a typical arrangement for the genus (Fig. 16 ). - Chaetal morphology: Dorsal ordinary chaetae of five types: long macrochaetae (Ml), short macrochaetae (Mc), mesochaetae and microchaetae. Long macrochaetae thick, slightly arched or straight, narrowly sheathed, feebly serrated, apically rounded or pointed (Figs 16 , 21 , 25 ). Macrochaetae Mc morphologically similar to long macrochaetae, but shorter. Mesochaetae similar to ventral chaetae, thin, smooth and pointed. Microchaetae similar to mesochaetae, but shorter. S-chaetae of tergites thin, smooth and short, notably shorter than nearby macrochaetae (Figs 16 , 21 , 24 ). - Antennae: Dorsal chaetotaxy of Ant. III-IV as in Fig. 17 and Table 5b. S-chaetae of Ant. IV of medium length and moderately thickened (Fig. 17 ). Apical vesicle distinct, trilobed. Ventral chaetotaxy of Ant. III with 14 ordinary chaetae, sense organ AOIII with long sensillum sgv and short peg (Fig. 18 , Table 5b). - Mouthparts: Buccal cone long with labral sclerifications ogival and spoon-like (Figs 16 , 22 ). Labral chaetotaxy: 4/2, 4 (Fig. 23 ). Labium with four basal, three distal and four lateral chaetae, papillae x absent. Maxilla relatively thick and styliform (Fig. 20 ). Mandible thin with two basal and two apical teeth (Fig. 19 ). - Dorsal chaetotaxy and tubercles: Head without chaetae L3 (Fig. 16 , Table 5a). Tubercles Di on Th. I not differentiated. Thorax with chaetae De2 and De3 free (Fig. 16 ). On Abd. I-III, the line of chaetae De1-chaeta s non perpendicular to the dorsomedian line. Abd. I-III with chaetae De3 free (Fig. 21 ). On Abd. V tubercle (Di+Di) with 3+3 chaetae. Abd. VI well visible from above (Fig. 21 ). - Ventral chaetotaxy: On head, groups Vea, Vem and Vep with 3, 4, 4 chaetae respectively. Group Vi on head with 6 chaetae. On Abd. IV, furca rudimentary without microchaetae. On Abd. V, chaetae Vl present and chaetae L’ absent. Legs: Chaetotaxy of legs as in Table 5c. Claw without internal tooth. On tibiotarsi, chaeta M present and chaetae B4 and B5 relatively short and pointed.

Etymology.

The name cochlearifera refers to the spoon-like shape of the labral sclerifications of this species.

Remarks.

E. cochlearifera sp. nov. is unique and differs from other species of the genus by the spoon-like shape of the apical labral sclerifications. In general appearance (e.g. dorsal chaetotaxy of head and thorax) the new species strongly resembles E. annae Smolis & Skarżyński, 2020, E. dentifera Smolis et al., 2007 and E. lusatica (Dunger, 1979). However, they can be easily distinguished by the following characters: number of chaetae Dl on the head (six in Endonura cochlearifera , Endonura annae and Endonura dentifera , five in Endonura lusatica ), number of chaetae (L+So) on the head (eight in Endonura annae , nine in Endonura cochlearifera and Endonura lusatica , 10 in Endonura dentifera ), number of ordinary chaetae (De+Dl+L) on Abd. V (8-9 in Endonura cochlearifera , 5 in Endonura annae , 7 in Endonura lusatica , 8 in Endonura dentifera ), presence of chaetae L’ on Abd. V (absent in Endonura cochlearifera and Endonura dentifera , present in Endonura annae and Endonura lusatica ), length and shape of chaetae B4 and B5 on tibiotarsi (short and acute in Endonura cochlearifera and Endonura annae , elongate and clavate in Endonura lusatica and Endonura dentifera ) and presence of internal tooth on claw (absent in Endonura cochlearifera , present in Endonura lusatica and Endonura dentifera ). All differences between E. cochlearifera sp. nov. and the related species mentioned above are summarised in Table 6.

Figures

Figure 16 - 25. Endonura cochlearifera sp. nov.: 16 dorsal chaetotaxy of head and Th.; 17 dorsal chaetotaxy of Ant. III-IV; 18 ventral chaetotaxy of Ant. III; 19 mandible; 20 maxilla; 21 dorsal chaetotaxy of Abd. III-VI; 22 ventral sclerifications of labrum; 23 chaetotaxy of labrum; 24 sensillum of Abd. V; 25 chaeta Di 1 of Abd. V.