Axonopsis truncata, Smit, Harry & Pešić, Vladimir, 2014

Smit, Harry & Pešić, Vladimir, 2014, Water mites from Mount Kinabalu and the Crocker Range, Borneo, Malaysia (Acari: Hydrachnidia), with the description of 34 new species, Zootaxa 3876 (1), pp. 1-71 : 54-56

Axonopsis truncata n. sp.

( Figs. 32A–G )

Type series. Holotype male, Kipungit River, Poring Hot Springs, Mt Kinabalu, Borneo, Malaysia, 6º 0 2.776 N 116º 41.432 E, alt. 568 m asl, 15-ix-2012. Paratypes: 10 males, 33 females, 1 nymph ( RMNH), 5 males, 5 females (SP).

Other material. 1/0/0, Kipungit River, hyporheic, Poring Hot Springs, Mt Kinabalu, 6º 0 2.776 N 116º 41.432 E, alt. 568 m asl, 15-ix-2012.

Diagnosis. Male with a short, truncated cauda, dorsal shield here bearing the excretory pore and a pair of glandularia (not visible in dorsal view).

Description. Cour yellowish. P2 ventrally in the centre with a rounded or bluntly triangular extension; P3 anterodorsally with a long seta; ventral margin of P4 with one long and one short, thin seta. Swimming setae: IIleg-5, 2; III-leg-4, 2; III-leg-5, 3; IV-leg-4, 2 and IV-leg-5, 3.

Male: Posterior part of idiosoma reddish, idiosoma 441 (413–458) long and 340 (336–352) wide. Anterior idiosoma margin straight to slightly concave. Dorsal shield 308 (312–324) wide, with five pairs of glandularia, posteriorly with a short, truncated extension. At the base of this extension a pair of large glandularia, on extension itself the excretory pore and a pair of smaller glandularia. No glandularia in dorsal furrow. Tips of Cx-I not extending to anterior idiosoma margin, with a pointed, anterolaterally directed extension. Suture lines of coxae obliterated. Genital field with three pairs of acetabula, in oblique posterior view the first pair bean-shaped, the second and third pair subtriangular; gonopore 44 long. Length/height of P1-P5: 29/17, 50/46, 27/22, 70/24, 24/12; Length of I-leg-4–6: 50, 60, 50. Length of IV-leg-4-6: 70, 75, 66. Fourth legs not modified.

Female: Idiosoma 436 (397–462) long and 348 (340–356) wide. Dorsal shield 316 (300–332) wide, with seven pairs of glandularia (one of them lying caudally); excretory pore fused with dorsal shield, lying caudally and together with flanking glandularia not visible in dorsal view. Genital field with acetabula in triangular arrangement. Length/height of P1-P5: 26/20, 50/44, 25/24, 70/22, 24/12. Length of I-leg-4–6: 46, 52, 47. Length of IV-leg-4–6: 66, 70, 60.

Deutonymph: Idiosoma 340 long and 292 wide. Dorsal shield 211 long and 194 wide. Coxal field with a straight posterior margin, laterally pointed extensions of anterior coxae absent. Genital field two pairs of acetabula.

Etymology. Named for the truncated posterior extension of the male dorsal shield.

Remarks. Both sexes of the new species differ from all other species of the subgenus in the formation of the P- 4 setae (both fine, in other species one setae stronger – this character state is no more diagnostic for the subgenus).

However, A. truncata has many other character states which justify the attribution to Paraxonopsis : (1) absence of glandularia in the dorsal furrow, (2) Cx-I/-II without hook-like lateral extensions, (3) male IV-legs not modified, (4) apodemes of gnathosoma of moderate lngth and (5) presence of a pair of glandularia between IV-leg sockets and genital field. Furthermore, the male can be separated from other Paraxonopsis species by the pronounced posterior extension of the dorsal shield, the female in the tips of Cx-I lying far away from the anterior idiosoma margin.

Distribution. Borneo.

Figures

FIGURES 32 A – G. Axonopsis truncata n. sp., holotype male A – D, paratype male E, paratype female F – G. A = dorsal view; B, G = ventral view; C = posterocaudal view; D – E = palp; F = dorsal view. Scale bars = 50 Μm.