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The Tardigrada Fauna of China with Descriptions Of Zoological Studies 46(2): 135-147 (2007) The Tardigrada Fauna of China with Descriptions of Three New Species of Echiniscidae Xiao-Chen Li*, Li-Zhi Wang, and Di Yu College of Life Sciences, Shaanxi Normal University, Xian 710062, China (Accepted March 3, 2006) Xiao-Chen Li, Li-Zhi Wang, and Di Yu (2007) The Tardigrada fauna of China with descriptions of three new species of Echiniscidae. Zoological Studies 46(2): 135-147. The Tardigrada fauna of China is summarized. Pseudechiniscus beasleyi sp. nov., Echiniscus nelsonae sp. nov., and E. shaanxiensis sp. nov. from the Qinling Mountains of central Shaanxi Province, China are described as new to science. Photomicrographs and draw- ings are provided to illustrate the morphological characters of the new species. Four new species records of ˆ ˆ ˆ the Tardigrada are also reported from the Qinling Mountains: E. ramazzottiˆ Binda and Pilato, E. mediantus Marcus, E. tardus Mihelcic (Echiniscidae), and Diphascon rivularis (Mihelcic) (Hypsibiidae). Type specimens are deposited at the College of Life Sciences, Shaanxi Normal University, Xian. A key to Chinese species of the Tardirada is also given. http://zoolstud.sinica.edu.tw/Journals/46.2/135.pdf Key words: Tardigrada fauna, Taxonomy, New Species, New record, China. ˆ Since the German priest J. A. E. Goeze E. ramazzotti Binda andˆ Pilato, E. mediantus ˆ described a freshwater tardigrade for the first time Marcus, E. tardusˆ Mihelcic, and Diphascon rivu- in 1773 (Ramazzotti and Maucci 1983, Nelson laris (Mihelcic). All specimens are deposited at 1991, Kinchin 1994), over 960 species of the College of Life Sciences, Shaanxi Normal Tardigrada have been described (Guidetti and University, Xian, China. These new species and Bertolani 2005). Of all the species described, the new record species are described and figured most are from European countries, such as Italy, in this article. The Tardigrada fauna of China is Germany, Poland, and the UK. Tardigrades are summarized. A key to Chinese species of the also well studied in the US, Japan, and Australia. Tardigrada is also given. However, the Tardigrada is relatively poorly stud- ied in China although research in Chinese tardi- grades has a history of 70 yrs. This situation has MATERIALS AND METHODS changed favorably in the past few years. So far, more than 16 papers by Chinese researchers on Specimens were extracted from moss sam- tardigrades have been published, and 45 species ples using a pipette and were fixed by boiling 85% , of Tardigrada have recently been reported or alcohol. All specimens were mounted in Hoyer s described from China. medium on microscope slides for identification, In 2004 and 2005, the authors collected 3 and the coverslips were sealed with epoxy paint. new species and 4 new species records of the Observations and measurements were made Tardigrda from the northern slopes of the Qinling using phase-contrast microscopy (PCM) (Leica Mountains of central Shaanxi Province, China. DM LB2,Germany) with an eyepiece micrometer. They are Echiniscus nelsonae sp. nov., E. shaanx- Photomicrographs were made using PCM with a iensis sp. nov., Pseudechiniscus beasleyi sp. nov., digital camera (Leica DFC Twain 6.1.1). Line *To whom correspondence and reprint requests should be addressed. Tel: 86-29-85310266. Fax: 86-29-85303736. E-mail:[email protected] 135 136 Zoological Studies 46(2): 135-147 (2007) drawings were made using PCM with a camera plate, 1st paired-plates, 2nd median plate trans- lucida. For scanning electron microscopy (SEM), versely divided into 2 parts by a ridge, 2nd paired- fixed tardigrades were dehydrated in absolute plates, 3rd single median plate, and terminal plate alcohol, transferred to amyl acetate, and dried by with 2 usual notches (Figs. 1, 2); all plates decorat- the critical point method. Individuals were mount- ed with closely spaced polygons and irregular ed on SEM stubs and coated with 2-3 nm of gold pores (Figs. 3, 4), similar to cuticular sculpturing of (Nelson and McInnes 2002). E. cheonyoungi Moon and Kim, and the terminal In the description of Diphascon rivularis, pt is plate with more and larger pores than on other the percent ratio between the length of a structure plates (the largest pore on terminal plate 3.3 µm in and the length of the buccal tube measured from diameter, the largest polygon on terminal plate 2.4 the mediodorsal transversal ridge to the base of µm in longitudinal diameter) (Figs. 1, 3, 4); anterior the pharyngeal apophyses (Pilato 1981). part of median plate 2 smooth, cuticular sculpture absent on ventral side of body; dentate collar with 8 teeth present on 4th pair of legs, a papilla-like SYSTEMATIC ACCOUNTS projection also present on lateral surface of 4th pair of legs, basal spurs which curve toward base Echiniscidae Kristensen and Hallas (1980) present on 2 middle claws of all legs (Figs. 5, 6). Echiniscus nelsonae sp. nov. Eggs unknown. (Figs. 1-6, Table 1) Remarks: The paratypes are similar to the holotype in terms of the qualitative characters. Material examined: Holotype (♀) (slide no. Etymology: This species is named in honor of MTQ004) and 2 paratypes (slide nos. MTQ0041, Dr. Diane R. Nelson, professor at the Department ♂; MTQ00411, ♀) collected from Mt. Taibai, the of Biological Sciences, East Tennessee State highest peak of Qinling Mts., at 3320 m (33 56.66'N, University, Johnson City, TN, USA. 107 46.12'E) on 7 Aug. 2005. ° Differential diagnosis: Echiniscus nelsonae °Description of the holotype: Color red. sp. nov. is similar to E. maesi Séméria (1985), but Eyespots present. Cephalic appendages including differs from it in having the 3rd median plate and internal buccal cirrus, cephalic papilla, external cirrus D instead of spine D. This new species dif- buccal cirrus; lateral and dorsal appendages fers from E. shaanxiensis sp. nov. in lacking Cd including cirrus A and E, clava and dorsolateral and possessing median plate 3. teeth B present; armor consisting of a single cephalic plate, a scapular plate, 1st single median Table 1. Dimensions (in µm) of Echiniscus nelsonae sp. nov. and E. shaanx- iensis sp. nov Structure E. nelsonae sp. nov. E. shaanxiensis sp. nov. Holotype Paratype 1 Paratype 2 Holotype Paratype Body length 203.6 146.2 172.3 161.8 187.9 Internal buccal cirrus 17.8 12.8 13.5 12.6 13.6 External buccal cirrus 22.2 14.4 18.3 13.5 18.3 Cephalic papilla 10.4 6.5 6.8 7.4 6.3 Cirrus A 53.5 41.8 41.8 45.7 62.6 Clava 7.8 4.4 5.2 5.2 6.5 Cd 20.9 18.3 Cirrus E 109.6 49.6 73.1 193.2 190.5 Claws on 1st pair of legs 13.5 11.7 9.2 11.2 12.1 Claws on 2nd pair of legs 14.6 12.8 9.6 12.5 13.1 Claws on 3rd pair of legs 16.2 13.8 10.8 13.3 13.8 Claws on 4th pair of legs 17.7 15.1 12.6 14.4 14.6 Cd represents the dorsal spines on the 1st paired-plates. Li et al. -- Tardigrada fauna of China 137 Echiniscus shaanxiensis sp. nov. rus A, clava, filament Cd, and cirrus E; armor con- (Figs. 7-12, Table 1) sisting of a single cephalic plate, a scapular plate, 1st single median plate, 1st paired-plates, 2nd Material examined: Holotype (♂) (slide no. median plate transversely divided by a fine ridge MTQ002) and 1 paratype (♂) (slide no. MTQ003) into 2 parts or undivided, 2nd paired-plates, termi- collected from Mt. Taibai at 3120 m (33 55.62'N, nal plate with 2 usual notches; 3rd median plate 107 46.53'E) on 8 Aug. 2005. ° absent (Figs. 7, 8); plates decorated with irregular °Description of holotype: Color red. Eyespots polygonal depressions (the largest polygonal present. Cephalic appendages including internal depression measuring 1.1 µm in longitudinal diam- buccal cirrus, cephalic papilla, and external buccal eter) (Figs. 9, 10); anterior part of median plate 2 cirrus; lateral and dorsal appendages including cir- smooth, cuticular sculpturing absent on ventral 1 7 2 8 3 9 pore polygon 4 56 10 11 12 Figs. 1-6. Echiniscus nelsonae sp. nov. (holotype). 1., 2. Figs. 7-12. Echiniscus shaanxiensis sp. nov. (holotype): 7., 8. Habitus showing cuticular sculpturing, dorsal plates, cephalic Habitus showing cuticular sculpturing, dorsal plates, cephalic appendages, and lateral and dorsal appendages. 3., 4. appendages, and lateral and dorsal appendages. 9., 10. Cuticular sculpturing on terminal plate. 5. Claws on leg 3; 6. Cuticular sculpturing on scapular plate. 11. Claws on leg 2. 12. Claws on leg 4 (1, 3. by phase-contrast microscopy). 1, 2. Claws on leg 4 (7, 9. by phase-contrast microscopy). 7, 8. scale bars = 50 µm; 3. scale bar = 15 µm; 4. scale bar = 5 µm; scale bars = 50 µm; 9. scale bar = 20 µm; 10. scale bar = 2 5., 6. scale bars = 5 µm. µm; 11, 12. scale bars = 5 µm. 138 Zoological Studies 46(2): 135-147 (2007) side of body; dentate collar with 8 or 9 teeth pre- cephalic plate, a scapular plate, 1st single median sent on 4th pair of legs, a papilla-like projection plate, 1st paired-plates, 2nd median plate, 2nd also present on lateral surface of 4th pair of legs, paired-plates, terminal plate; 3rd median plate basal spurs which curve toward base present on 2 absent; plates decorated with hexagonal sculptur- middle claws of 4th pair of legs, while spurs absent ing; dentate collar present on 4th pair of legs, a on 1st 3 pairs of legs (Figs. 11, 12). papilla-like projection also present on lateral sur- Eggs unknown.
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