Allonychiurus zhejiangensis, Chang, Liang & Sun, Xin, 2016

Chang, Liang & Sun, Xin, 2016, Two new species of Allonychiurus Yoshii, 1995 (Collembola, Onychiuridae) from eastern China, with a key to world species of the genus, Zootaxa 4061 (4), pp. 429-437 : 430

Allonychiurus zhejiangensis sp. nov.

Figs 1–17

Material examined. Holotype male, China, Zhejiang Province, Hangzhou City, Xihu Park (30°15’44’’ N, 120°08’41’’ E), 0 6 December 2014, litter and soil, Sun Xin leg. Paratypes 2 females, 7 males and 5 juveniles, same data as holotype.

Description. Body white in alcohol. Length of body 1.30–1.35 mm in females, 1.13–1.20 mm in males; holotype 1.15 mm. Shape of body: cylindrical with anal spines on papillae ( Fig. 1 ). Anal spines 0.3 times as long as inner edge of hind unguis.

Pso formulae 32/022/33353 dorsally and 12/000/21120 ventrally ( Figs 1, 8 ). Subcoxae 1 of legs I–III with 2 pso each. Psx only present ventrally, formula as 0/000/ 101000 ( Figs 1, 8 , 15 ). Subcoxae 1 of legs I–III without psx. Psp formulae 00/011/ 111100 dorsally and 00/111/0001m0 0 ventrally ( Figs 1, 8 ).

Head. Antennae as long as head. Length ratio of Ant. I: II: III: IV as about 1: 1.8: 1.8: 2.5. Subapical organite on Ant. IV with globular apex; basolateral ms above the second proximal row of chaetae ( Fig. 6 ). Ant. III sensory organ consists of 5 papillae, 5 guard chaetae, 2 small rods, and 2 smooth sensory clubs ( Fig. 7 ); lateral ms just behind sensory organ. Ant. II with 14 chaetae. Ant. I with 8 chaetae. Antennal base well marked. PAO with 13–14 compound vesicles arranged in two rows along axis of organ ( Fig. 3 ). Dorsal cephalic chaeta d0 present ( Fig. 10 ). On head 3+3 p-chaetae present between two posterior pso, p1 anterior to others. Mandible with strong molar plate and 4 apical teeth. Maxilla bearing 3 teeth and 6 lamellae. Maxillary palp simple with 1 basal chaeta and 2 sublobal hair ( Fig. 4 ). Labral chaetae 2/342 ( Fig. 2 ). Labium with 6 proximal, 4 basomedian (E, F, G, and f) and 5 basolateral (b, c, d, e, e’) chaetae ( Fig. 9 ); labial type AB, papillae A–E with 1, 4, 0, 3 and 3 guard chaetae respectively ( Fig. 5 ). Postlabial chaetae 4+4 along ventral groove ( Fig. 9 ).

Body chaetotaxy. S-chaeta distinguishable from ordinary chaeta, formulae as 2/022/222121 dorsally and 2/ 000/00010 ventrally ( Fig. 1 ). Tiny and blunt ms present on both Th. II and III ( Figs 1 , 11 ). Th. I tergum with 10+10 chaetae. Th. II–Abd. III terga with 3+3 chaetae along axial line respectively ( Fig. 1 ). Abd. IV tergum with axial chaeta p0, Abd. V tergum without axial chaeta, Abd. VI tergum with axial chaeta p0 ( Figs 1 , 12 ).Th. I–III sterna without chaetae.

Appendages. Subcoxae 1 of legs I–III with 4, 5 and 5 chaetae, subcoxae 2 with 0, 4 and 3 chaetae respectively. Coxae of legs I, II and III with 3, 9 and 12 chaetae, trochanters with 9 chaetae each and femorae with 15, 15 and 14 chaetae. Tibiotarsi of legs I, II and III with 17 (1, 7, 9), 19 (2, 8, 9) and 18 (2, 7, 9) chaetae, B7 absent on tibiotarsi I and III ( Figs 13, 14 ). Unguis without teeth. Unguiculus 0.9 times as long as inner edge of unguis, without inner basal lamella ( Figs. 13, 14 ). Ventral tube with 6+6 distal chaetae (2+2 of them inflated in males), without anterior and basal chaetae ( Fig. 8 ). Furca reduced to finely granulated area, with 4 small dental chaetae arranged in two rows posteriorly and two manubrial rows of chaetae ( Fig. 16 ).

Female genital plate with 13–18 chaetae, males with 44–54 chaetae. Anal valves with numerous acuminate chaetae; each lateral valve with chaetae a0, 2a1; upper valve with chaetae a0, 2b1, 2b2, c0, 2c1 and 2c2 ( Fig. 17 ).

Ecology. In litter and soil under broadleaved trees, in an urban recreational park.

Derivatio nominis. Named for the name of the province where the species was found.

Distribution. Known only from the type locality.

Discussion. The new species is peculiar among the species, which have the larger body size in the genus Allonychiurus , as having three pso on the ventral side of head, labial type AB, incomplete B-whorl on tibiotarsi I and III and smooth sensory clubs on the antennal III organ. The new species shares the same number of pso on Th. II and III terga with a number of known species, viz. A. donjiensis ( Lee & Kim, 1994) , A. flavescens ( Kinoshita, 1916) , A. indicus ( Choudhuri & Roy, 1965) , A. kimi ( Lee, 1973) , A. pseudocellitriadis ( Lee, 1974) , A. shanghaiensis ( Rusek, 1971) and A. pseudokimi sp. nov. described below. The main diagnostic characters are summarized in Table 1 . The new species is the most similar to A. indicus and A. pseudocellitriadis by the absence of pso on Th. I tergum, but they can be distinguished easily by the pso formula on the ventral side of body (12/000/ 21120 in the new species, 2/000/00000 in A. indicus and 11/000/01000 in A. pseudocellitriadis ).

Figures

FIGURES 1 – 8. Allonychiurus zhejiangensis sp. nov. 1, dorsal chaetotaxy; 2, labrum; 3, PAO and anterior cephalic pso; 4, maxillary palp; 5, labium; 6, antenna; 7, sensory clubs on Ant. III sensory organ; 8, ventral side of Abd. I – VI;. Scales: 0.1 mm (1, 6, 8), 0.01 mm (2 – 5, 7).

FIGURES 9 – 17. Allonychiurus zhejiangensis sp. nov. 9, ventral side of head; 10, right part of head; 11, right side of Th. II tergum; 12, right part of Abd. IV tergum; 13, distal part of leg I; 14, distal part of leg III; 15, central part of abdominal sternum III; 16, central part of abdominal sternum IV; 17, anal valves. Scales: 0.1 mm.