Koreanurina Najt and Weiner, 1992

Wu, Donghui, Bedos, Anne & Deharveng, Louis, 2014, First record of the genus Koreanurina Najt and Weiner (Collembola: Neanuridae: Pseudachorutinae) from China, with description of two new species from Changbai mountain, Journal of Natural History 48 (41 - 42), pp. 2579-2593 : 2581

Genus Koreanurina Najt and Weiner, 1992

Type species: Koreanurina szeptyckii Najt and Weiner, 1992 .

Redescription of the genus

Very small to small size (0.38–0.81 mm). Habitus flattened, regularly oval. Th I reduced, with 1 + 1 dorsointernal chaetae, its lateral parts not or weakly separated from head. Dorsal ordinary chaetae very short. S-chaetae long and thin, distributed as formula 2 + ms, 2/1, 1, 1, 1, 1, 1 from Th II to Abd V. Presence of large reticulated areas covering most of the dorsal side, delimited by very strong secondary granulation on head (one central, 1 + 1 posterior), Th II to Abd IV (1 + 1), and Abd V (one uneven). Colour white, blue or grey. Eyes reduced, pigmented in black. Post-antennal organ ( PAO) dorsal or dorsolateral, circular or ovoid, with 9–16 vesicles in one row. Mandibles with 5 teeth. Maxillae type as in Anurida , with dentate maxillary capitulum and three free lamellae (including the ‘maxillary capitulum’ sensu Najt and Weiner 1992). Labium truncated, short, with 3 chaetae in the distal group (A or B, C, D; L absent), 4 in the basal group (E, F, f, G), and 3 lateral (probably c, d, e); two large ovoid papillae (x) present. Labral chaetotaxy 2/2,3,5,2. Antennae short. Ant I with seven chaetae, Ant II with 11 or 12 chaetae. Ant III and IV fused dorsally. Sensory organ of antennal segment III complete, consisting of two S-microchaetae, two thick, subcylindrical guard S-chaetae and one ventrolateral S-chaeta. Ant IV with six thick, subcylindrical S-chaetae and a short dorsoexternal S-chaeta; subapical organite small, rooted deep into the integument; apical vesicle slightly bilobed or trilobed; no ventral sensory file. Head without uneven chaeta a0. Most chaetae of central plate of the head arranged along the lateral edges of this plate, except a group of 3 + 3 located within the posterior half of this plate. Ventral tube with 4 + 4 chaetae. Tibiotarsi with 18, 18, 17 or 19, 19, 18 chaetae, M absent or present. Claw toothless. Furca absent, furcal area with two small round swelling each with one chaeta. Thorax I separated from head, sometimes weakly, with at least 1 + 1 dorsointernal chaetae not integrated into head chaetotaxy. Abdomen VI reduced, most of its chaetae visible ventrally. No anal spines .

Discussion

The extent of dorsal reticulation on head and tergites in Koreanurina is unique among Pseudachorutinae , but similar to those of Caputanurininae , where reticulations are even more developed ( Lee 1983; Najt and Weiner 1992; Deharveng et al. 2011). The flattened habitus of Koreanurina also recalls that of Caputanurininae . Other characters are comparable to those observed in many Anurida Laboulbène, 1865 , where Th I is however more clearly individualized. According to Najt and Weiner (1992), Koreanurina is most similar to Anurida hexophthalmica Stach, 1949 from the Tatra mountains ( Poland) in its habitus, mouthparts, number and position of the eyes, postantennal organ, furca, reduced chaetotaxy and reduced Abd VI. The very close relationships between Koreanurina and Anurida Laboulbène, 1865 on one hand, and between Koreanurina and Caputanurininae on the other hand, and the distribution of the genus similar to that of Caputanurininae (Far-East Palaearctic) question the validity of the subfamily Caputanurininae .