| abstract | In this paper, two new species of the genus Hirstionyssus Fonseca, 1948 are described.
Hirstionyssus kirinensis, sp. nov.
Female (Fig. 1) Idiosoma oval, 0.56-0.60 mm long and 0.34-0.36 mm wide.
Dorsal plate undivided, covering most of the dorsum, 0.48-0.52 mm long and 0.28-0.30 mm wide (the widest point is about at the level of S5), posterior lateral margins narrowed posteriorly from the level of S5 to a rounded tip, with numerous small spots and 26 pairs of setae, I1 and I2 are smaller than the others. Unsclerotized portion of dorsum with about 12 pairs of setae.
Sternal plate rectangular, about twice as wide as long, anterior margin slightly convex, posterior margin straight or slightly concave. Genito-ventral plate tongue-like, slightly enlarged at the middle, narrowing progressively to a comparatively narrow extremity. There are numerous small even spots on this plate. Anal plate oblong, length to width being about 5:3 three peri-anal setae about as long as the anus. Uncovered ventral surface with 14-17 pairs of setae.
Coxal spurs: 0-1-2-0. The internal spur of the coxa III is slightly larger than the external one.
Male (Fig. 2) Body oval, 0.62 mm long and 0.38 mm wide. Dorsal plate somewhat resembles that of the female, but narrower (0.54 mm long and 0.30 mm wide), the spots and chaetotaxy as in the female.
Holoventral plate undivided. It is straight or slightly convex at the anterior margin, broader at the level of coxa III, narrower at the level of coxa IV, widening progressively to the level of Vl, which makes a neck before the anal portion. There are 9 paired and 1 unpaired setae on this plate. Uncovered ventral surface with about 15 pairs of setae.
Legs with claws and caruncle. Tarsus II with one pair of spur-like modified setae subapically. Coxal spurs: 0-1-2-1.
This new species is allied to Hirstionyssus minor Zemskaja et Piontkovskaja, 1957, but is easily distinguished by the following characters: (1) body larger, (2) dorsal plate narrower posteriorly, (3) genito-ventral plate tongue-like, with narrow posterior extremity, (4) a larger number of setae on the uncovered surface (than on the Hirstionyssus minor).
Holotype (? ) collected off Myospalax psilurus Milne-Edwards in October, 1959 from Kirin Province. Allotype (?) and Paratypes (12 ? ?, 3 ? ?) collected from Myospalax psilurus in May, 1962, from Kirin Province.
Hirstionyssus sub-mionr, sp. nov.
Female (Fig. 3) Idiosoma oval, never longer than 0.52 mm.
Dorsal plate covering almost the entire dorsum, tapering progressively from the level of S2 toward a rounded posterior end. There are numerous small even spots and 26 pairs of dorsal setae on its surface. F3 and M11 of the dorsal setae are longer than those on marginal portion, I1, I2, D1-D7 are very small. Uncovered dorsal surface with 16-20 pairs of setae.
Sternal plate rectangular, with four acute angles, slightly convex on the anterior margin and slightly concave on the posterior margin; 3 pairs of sternal setae subequal; 2 pairs of slit-like pores distinct. Metasternal plate with 1 pair of Mst, about as long as the St setae; Genito-ventral plate very large, somewhat rectangular, about twice as long as wide; lateral margins straight and parallel; posterior end truncate. There are numerous small spots and 1 pair of usual setae on this plate. Genital fold very large. Anal plate slightly widened anteriorly; cribrum with fine teeth; paired setae situated beside the anterior end of the anus; the post-anal setae as long as the paired setae. Unsclerotized portion of the venter with about 14 pairs of setae. Peritreme extending anteriorly to the middle of coxa I. Peritremalia extending posteriorly to the middle of posterior margin of coxa IV.
Legs stout and strong. Tarsus II with one pair of spur-like modified setae. Coxae with spurs as: 0-1-2-0. The internal spur of the coxa III is slightly larger than the external spur.
Holotype (? ) and paratypes (7 ? ?) collected from the nests of Myospalax aspalax Pallas in May, 1962 from Kirin Province.
This new species is closely allied to Hirstionyssus minor Zemskaja et Piontkovskaja, 1957, but is distinguished from the latter by the following characters: (1) posterior end of dorsal plate narrw, (2) genito-ventral plate rectangular, (3) formula of coxal spurs: 0-1-2-0
Type specimensof these two new species are deposited in the Department of Biology, Kirin Medical College, Changchun, China. |