Biserovus xiae, Li, Xiaochen, Su, Lina & Yu, Di, 2004

Li, Xiaochen, Su, Lina & Yu, Di, 2004, Biserovus xiae sp. n. and Doryphoribius qinlingense sp. n., new species of eutardigrades from China, Zootaxa 660, pp. 1-7 : 2-3

Biserovus xiae sp. nov.

Fig.1A–C

Holotype: Adult, sex unknown (slide number 04/02/002), collected on Zhaobaoshan mountain in March, 2004. The type is deposited at College of Life Sciences, Shaanxi Normal University.

Paratype: None.

Type locality: Zhaobaoshan mountain, Zhenhai County, Zhejiang Province, P. R. China.

Etymology: This species is named after Madam Xia, who kindly sent us the material for investigation.

Diagnosis: Bucco­pharygeal tube wide, subdivided into a rigid anterior portion with a ventral lamina and a posterior flexible portion with spiral thickening on the wall. Buccal aperture with ten peribuccal lamellae. Pharyngeal tube portion very short. Diploclaws formed by a fine short common tract, lunule absent.

Description of the holotype: Body length 368.6 µm, cuticle smooth without pearl­like sculpture, colorless, eyes absent; the bucco­pharyngeal tube is subdivided into a rigid anterior portion and a posterior flexible portion with spiral thickening on the wall ( Fig.1A ), total bucco­pharyngeal tube length 41.8 µm, buccal tube length 31.3 µm, 75.0% with respect to the total length of the bucco­pharyngeal tube, buccal tube width 4.7µm (pt = 15.0), stylet supports inserted on the buccal tube at 91.7 of its length (pt = 91.7), stylet furcae well­developed, pharyngeal tube (the flexible annulated portion) length 10.4 µm, the buccal tube with ventral lamina much longer than the pharyngeal tube, mouth terminal with ten small peribuccal lamellae, dorsal buccal apophyses absent, ventral buccal apophyses unclear; pharyngeal bulb oval, pharyngeal apophyses present, macroplacoid row plus microplacoid 22.2 µm long (pt = 70.9), three macroplacoids rod­shaped, equal length, 5.2 µm long (pt = 16.7), microplacoid 3.7 µm long (pt = 11.7), diploclaws on all legs similar in size and shape, small, with a common tract fine and short; main branch 7.8 µm long (pt = 25.0) and the secondary branch 6.5 µm long (pt = 20.2); main branch with accessory points; lunules absent ( Fig. 1 BC). Eggs unknown.

Remarks: The genus Biserovus was instituted for B. bindae which was originally ascribed to Pseudodiphascon ( Christenberry & Higgins, 1979) . The genus Pseudodiphascon was also abolished by Guidetti & Pilato (Guidetti & Pilato, 2003). The genus Biserovus contains only one species B. bindae . B. xiae sp. nov. differs from B. bindae mainly by having a shorter and wider bucco­pharyngeal tube with the buccal tube width pt = 15.0 which is much larger than the average pt = 7.1 in B. bindae based on measurements of the figures ( Guidetti & Pilato, 2003; Ramazzotti and Maucci, 1983), by having the pharyngeal tube much shorter than the buccal tube with a stylet support pt = 91.7 which is larger than the average pt = 81.9 in B. bindae based on measurements of the figures ( Guidetti & Pilato, 2003; Ramazzotti and Maucci, 1983), by having a longer buccal tube, 75.0% with respect to the total length of the bucco­pharyngeal tube, whereas average 54.7% in B. bindae , especially by having a narrower and shorter common tract and much longer principal and secondary branches of the double claw, by having three macroplacoids the same in length.

Figures

FIGURE 1. A – C, Biserovus xiae sp. nov.: A, bucco­pharyngeal apparatus; B, claws of the second pair of legs; C, claws of the fourth pair of legs. D – F, Doryphoribius qinlingense sp. nov.: D, buccopharyngeal apparatus, E, claws of the first pair of legs; F, claws of the second pair of legs. (Scale bars = 10 µm.)