Pseudechiniscus yunnanensis, Wang, 2009

Wang, Lizhi, 2009, Tardigrades from the Yunnan-Guizhou Plateau (China) with description of two new species in the genera Mixibius (Eutardigrada: Hypsibiidae) and Pseudechiniscus (Heterotardigrada: Echiniscidae), Journal of Natural History 43 (41 - 42), pp. 2553-2570 : 2557-2559

Pseudechiniscus yunnanensis sp. n.

( Figure 1A–D )

Material examined

Holotype (adult; (♀); slide no. YN0808021), three paratypes (adults; slide nos YN0808020, YN0808022, YN0808023) were collected from Shilin County, Yunnan Province, China (24°76′N, 103°27′E) at 1800m asl. The specimens are deposited at the College of Life Sciences, Shaanxi Normal University, P. R. China.

Diagnosis

Small in size. Colour red. Black eyespots present. Head with normal appendages except clava rather long and robust. Dorsal plates and areas between dorsal plates covered with sculpture composed of distributed granules, connected by lines so as to form a reticular design. Ventral cuticular smooth. Cephalic plate faceted; armour consists of single cephalic plate, scapular plate transversely subdivided, first single triangle-shaped median plate, first paired-plates, second single median plate, second paired-plates, third single median plate, the caudal margin of the first and second paired-plates with a small lobe along the dorsal median line; pseudosegmental plate with two triangle-shaped lobes on the posterior edge; terminal plate without notches. All median plates undivided and somewhat poorly developed. A spine on the leg I absent. A papilla present on the external side of the fourth pair of legs near their bases, spurs absent on all claws. Dentate collar on leg IV absent.

Description

Small in size (see Table 2). Colour red. Small black eyespots present. Cephalic appendages include internal buccal cirrus, a wide cephalic papilla, external buccal cirrus, cirrus A, and rather long and robust clava (see Figure 1C and Table 2). No other appendages present. Dorsal plates and areas between dorsal plates covered with sculpture composed of distributed granules (diameter about 2.42 ± 0.19 µm), connected by lines so as to form a reticular design with the granule located at the crossing of lines (see Figure 1B ). Ventral cuticle smooth. Cephalic plate faceted; armour consists of single cephalic plate, scapular plate transversely divided into an anterior part and posterior part, first single triangle-shaped median plate, first paired-plates, second single median plate, second paired-plates, third single median plate, the caudal margin of the first and second paired-plates with a small lobe along the dorsal median line; pseudosegmental plate with two triangle-shaped lobes on the posterior edge; terminal plate without notches (see Figure 1A ). All median plates undivided and somewhat poorly developed. A spine on the leg I absent. A papilla present on the external side of the fourth pair of legs near their bases; dentate collar absent; Legs short, claws slightly curved, without spurs near the bases on each leg (see Figure 1D ). Eggs unknown.

Etymology

This species is named after the locality, Yunnan Province, China.

Remarks

This new species is similar to Pseudechiniscus pilatoi Li, 2007 . It differs from P. pilatoi in having a different pseudosegmental plate with two triangle-shaped lobes, the first and second paired-plates with a small lobe on the posterior edge, and shape of first median plate. This species belongs to the novaezeelandiae -group within this genus. It differs from P. spinerectus Pilato, Binda, Napolitano and Moncada, 2001 ( Pilato et al. 2001) in having the second median plate undivided, the size of granules on plates with lines connecting not increasing, inner claw without spurs, and shape of first median plate. It differs from P. bartkei Weglarska, 1962 in having small supplementary plates absent, the first and second paired-plates with a small lobe on the posterior edge, and inner claw without spurs.

Figures

Figure 1. Pseudechiniscus yunnanensis sp. n. (A) Habitus in dorsal view (holotype); (B) granules on dorsal plates (holotype); (C) clava (holotype); (D) claws on fourth pair of legs (holotype). Notes: arrow indicates the small lobes of the first and second paired plates; scale bars: 40 µm (A); 10 µm (B, D); 5 µm (C).