Bryochoerus liupanensis, Xue, Jing, Li, Xiaochen, Wang, Lizhi, Xian, Panpan & Chen, Huiqing, 2017

Xue, Jing, Li, Xiaochen, Wang, Lizhi, Xian, Panpan & Chen, Huiqing, 2017, Bryochoerus liupanensis sp. nov. and Pseudechiniscus chengi. sp. nov. (Tardigrada: Heterotardigrada: Echiniscidae) from China, Zootaxa 4291 (2), pp. 324-334 : 325-327

Bryochoerus liupanensis sp. nov.

( Table 1, Figs. 1–3 )

Type material. Holotype: Female, slide number: xnc02006.

Type locality. 35.36043N, 106.31239E (35°21′37.55″ N, 106°18′44.60″E), 1,986m asl, the Liupanshan National Forest Park , Jingyuan County, Ningxia Hui Autonomous Region, China.

Paratypes: slide number: xnc03003, xnc03005, xnc03006, xnc03009.

Type repository. Li’s tardigrade collection, Molecular Ecology , Department of Biology , College of Life Sciences of Shaanxi Normal University, China.

Diagnosis. Apart from the head appendages including cirrus internus, cephalic papillae and cirrus externus, only lateral cirrus A with clava present; dorsal plates and lateral plates with double sculpture including large bright roundish granule-like dots and small dark roundish dots; median plates 1 and 2 divided transversely into four parts, median plate 3 divided transversely into three parts; two lateral plates on each side of all median plates, 12 in total; paired plates with a transverse smooth band; terminal plate with two longitudinal ridges which divided the terminal plate into three parts, terminal plate without notches; ventral side of body without plates or platelets; papilla not visible and dentate collar absent on legs IV; small spurs present on internal claws on all legs.

Description. Colour orange. Eye spots absent or not visible after slide preparation. Apart from head appendages, including cirrus internus, cirrus externus and cephalic papillae (secondary clava), only lateral cirrus A with clava (primary clava) are present; cephalic papillae drop-shaped; stylet supports not visible, pharyngeal bulb roundish; dorsal plates comprise of head plate, scapular plate, first median plate, first paired plates, second median plate, second paired plates, third median plate, and terminal plate; all median plates divided transversely, median plate 1 and median plate 2 divided into four parts, while median plate 3 divided into three parts, the normal parts of all median plates are the same as Bryodelphax species, however all median plates are followed with two intersegmental plates, two lateral plates present on each side of all median plates, 12 in total, two paired plates with a transverse smooth band, terminal plate with two longitudinal ridges which divide terminal plate into three parts, terminal plate without incisions; all plates, including dorsal plates and lateral plates, with “double sculpture”, including large bright roundish pores and small dark roundish dots that are pillars within the cuticle, pores are scarce and distributed loosely whereas dark dots are arranged regularly and densely ( Figs. 1 a, 2); ventral side without plate or platelets ( Fig. 1 b).

Spine on legs I and papilla on legs IV not visible under light microscope. Dentate collar absent on legs IV. Internal claws on all legs with small spur, external claws spurless ( Fig. 3 a), the upper part of all legs were covered with plate with sculpture of small dots ( Fig. 3 b).

Eggs unknown.

For measurements see Table 1.

Remarks. Please see Michalczyk & Kaczmarek 2006 or Kaczmarek et al. 2012 for more information on the anatomy of ‘double sculpturing’. Whether the spine on legs I and papilla on legs IV are indeed absent, has to be confirmed by SEM observations in the future.

Structure xnc02006 xnc03003 xnc03005 xnc03006 xnc03009

female female female female female Etymology. The new species is named after the type locality.

Differential diagnosis. The monotypic genus Bryochoerus contained only the nominate species Bryochoerus intermedius . There are three subspecies in B. intermedius . They are B. i. intermedius ( Murray, 1910) , B. i. hawaiicus ( Thulin, 1928) and B. i. laevis ( Marcus, 1936) ( Kristensen 1987; Ramazzotti & Maucci 1983). Bryochoerus liupanensis sp. nov. differs from Bryochoerus intermedius intermedius in having orange colour instead of colourless, or yellowish, or else greenish-yellow as in B. i. intermedius ; a different cuticular sculpture; presence of lateral plates; lacking papilla and dentate collar on legs IV; and presence of spurs on the internal claws of all legs. The new species differs from B. i. hawaiicus in having different cuticular sculpture; presence of lateral plates; and presence of spurs on the internal claws of all legs. Bryochoerus liupanensis sp. nov. differs from B. i. laevis in having a different cuticular sculpture; presence of lateral plates in a different shape; a facetted terminal plate; lacking spine on the first pair of legs; and lacking papilla and dentate collar on legs IV.

Figures

FIGURE 1. Bryochoerus liupanensis sp. nov. (holotype). a, habitus in dorsal view under 400 × magnification focused to show the cuticular sculpture on the dorsal plate; b, habitus in ventral view at 400 × magnification focused to show the ventral side of body and the claws. Scale bars = 30 µm.

FIGURE 2. Bryochoerus liupanensis sp. nov. a, anterior part of body in dorsal view under 1000 × focused to show the cuticular sculpture on the dorsal plates (holotype); b, habitus in dorsal view under oil immersion lens at 1000 × magnification focused to show the two segmental plates after the third median plate (paratype, slide number xnc 03003); c, posterior part of body in dorsal view under 1000 × focused to show the cuticular sculpture on the dorsal plates (holotype). I – IV = segmental plates, hp = head plate, lp 1 a, lp 1 b, lp 2 a, lp 2 b, lp 3 a and lp 3 b = lateral plates, m 1, m 2 and m 3 = median plates, m 1 a, m 1 b, m 2 a, m 2 b, m 3 a and m 3 b = intersegmental plates. Scale bars = 30 µm.

FIGURE 3. Bryochoerus liupanensis sp. nov. (holotype). a, Claws under 1000 × focused to show the spur on the internal claws on the second pair of legs, the arrows point at the spur; b, hind legs under 1000 × focused to show the sculptured let plate, the arrow points at cuticular sculpture. Scale bars = 10 µm.