Endonura crimica, 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 crimica sp. nov.

Figs 26-36, Tables 7a-c, 8

Type material.

Holotype: adult female on slide, Crimea, Jaltynskyi Nature Reserve (34 24.344 N; 44 55.137 E), 570 m alt., mixed forest (pine, beech), 3.II.2016, leg. D. Shitikov, A. Szarikov (DIBEC). Paratype: subadult male on slide, Crimea, Ajudag near Gurzuf, 450 m alt., oak forest, 6.II.2015, leg. D. Shitikov, A. Szarikov (MSPU).

Diagnosis.

2+2 pigmented eyes. Buccal cone relatively short and narrow, labrum not ogival. Head with chaetae A, B, C, D 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 present. 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: 1.05 (subadult male) to 1.15 mm (holotype) (without antennae). - Colour: body pale bluish grey (alive and in alcohol). 2+2 black eyes, in a typical arrangement for the genus (Fig. 28 ). - 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 28 , 29 , 34 ). 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 28 , 30 , 34 ). - Antennae: Dorsal chaetotaxy of Ant. III-IV as Fig. 26 and Table 7b. S-chaetae of Ant. IV of medium length and moderately thickened (Fig. 26 ), sensillum sgd notably short. Apical vesicle distinct, trilobed. Ventral chaetotaxy of Ant. III with 14 ordinary chaetae, sense organ AOIII with long sensillum sgv and short peg (Fig. 27 , Table 7b). - Mouthparts: Buccal cone relatively short with labral sclerifications not ogival (Fig. 33 ). Labral chaetotaxy: 4/2, 4 (Fig. 33 ). Labium with four basal, three distal and four lateral chaetae, papillae x absent. Maxilla styliform (Fig. 31 ), mandible thin and tridentate (Fig. 32 ). - Dorsal chaetotaxy and tubercles: Head without chaetae E and L3 (Fig. 28 , Table 7a). Tubercles Di on Th. I developed. Th. III with chaetae De3 free (Fig. 28 ). 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. 34 ). On Abd. V tubercle (Di+Di) with 3+3 chaetae. Abd. VI partially visible from above (Fig. 34 ). - 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. One chaeta L on Abd. IV free (Fig. 35 ). On Abd. V, chaetae Vl and chaetae L’ present. Legs: Chaetotaxy of legs as in Fig. 36 and Table 7c. Claw without internal tooth (Fig. 36 ). On tibiotarsi, chaeta M present and chaetae B4 and B5 relatively short and pointed.

Etymology.

The name crimica refers to the geographic area of its collecting.

Remarks.

E. crimica sp. nov. belongs to a very small group of Endonura characterised by a broad and short (equal to or shorter than tubercle Oc) cephalic tubercle Af. In addition to the new species, this group includes E. taurica (Stach, 1951) and E. gracilirostris Smolis et al., 2007. E. crimica sp. nov. can be reliably distinguished from these Crimean species by the following characters: presence/absence of cephalic chaetae E (present in Endonura crimica , absent in Endonura taurica and Endonura gracilirostris ), presence/absence of cephalic chaeta O (present in Endonura crimica and Endonura gracilirostris , absent in Endonura taurica ), shape of labrum (not ogival in Endonura crimica and Endonura taurica , ogival in Endonura gracilirostris ), presence/absence of tubercle Di on Th. I (present in Endonura crimica , absent in Endonura taurica and Endonura gracilirostris ), position of chaetae De2 on Th. II and III (within tubercle in Endonura crimica , free in Endonura taurica and Endonura gracilirostris ), and length and shape of tibiotarsal chaeta B4 (short and acute in Endonura crimica , elongated and clavate in Endonura taurica and Endonura gracilirostris ). Morphologically, E. crimica sp. nov. also closely resembles E. colorata (Gama, 1964), a species known only from Portugal ( Jordana et al. 1997). However, these species differ in several crucial characters: position of cephalic chaetae D (free in Endonura crimica , located inside tubercle Cl in Endonura colorata ), number of me chaetae on furca rudimentary (5-7 chaetae in Endonura crimica , 8-9 chaetae in Endonura colorata ), number of ordinary chaetae (De+Dl+L) on Abd. V (7 in Endonura crimica , 6 in Endonura colorata ). Furthermore, the ratio Di1/Di2/Di3 on Abd. V is 50:21:3 in Endonura crimica and 40:22:10 in Endonura colorata . A summary of the differences between these species is given in Table 8.

Figures

Figure 26 - 36. Endonura crimica sp. nov.: 26 dorsal chaetotaxy of Ant. III-IV; 27 ventral chaetotaxy of Ant. III; 28 dorsal chaetotaxy of head and Th.; 29 chaeta Di 1 of Abd. V; 30 sensillum of Abd. V; 31 maxilla; 32 mandible; 33 chaetotaxy and ventral sclerifications of labrum; 34 dorsal chaetotaxy of Abd. III-VI; 35 tubercle L of Abd. IV; 36 tibiotarsus and claw of leg III, lateral view.