Cosmolaelaps chianensis (Gu)
- Dataset
- New species and new records of Cosmolaelaps Berlese (Acari: Laelapidae) from Russia, with a review of the Russian species of the genus
- Rank
- SPECIES
Classification
- kingdom
- Animalia
- phylum
- Arthropoda
- class
- Arachnida
- order
- Mesostigmata
- family
- Laelapidae
- genus
- Cosmolaelaps
- species
- Cosmolaelaps chianensis
description
(Figures 1 – 7)
discussion
Remarks. Cosmolaelaps chianensis was described from China (Gu, 1990). It has been found associated with Mus pahari Thomas (Rodentia: Muridae). The description of this species is brief and both the description and illustrations lack many important details. Ma (2006) considered that Cosmolaelaps hefeiensis is a junior synonym of C. chianensis. However, Ma (2006) did not provide any explanation for this decision, nor did he provide the details of the examined specimens. Cosmolaelaps hefeiensis was also described from China (Xu & Liang, 1996). It has been found from moss (Xu & Liang, 1996) and this species also has been recorded from soil in Republic of Korea (Keum et al., 2017) and Russia (Marchenko, 2017). By comparing the descriptions and figures of these two species, we found some distinguishing morphological differences: (1) dorsal shield setae J 5 and Z 5 more or less similar in length, and j 1 considerably shorter than j 2 in C. hefeiensis (see Xu & Liang, 1996 and Fig. 1 of current study), while in C. chianensis setae Z 5 are obviously longer than J 5 and j 1 is similar length to j 2 (see Fig. 1 in Gu, 1990); (2) body size 395 long, 255 wide in C. chianensis (see Gu, 1990), while in C. hefeiensis size of body larger, especially its width (484 – 560 long, 345 – 391 wide) (see Xu & Liang, 1996). Our efforts to see type material of these two species were not successful so, in this study we follow Ma’s (2006) treatment and provisionally retain these two species as synonyms until further comparative studies clarify their relationship. Our concept of the species is based on that of Xu & Liang (1996) and the diagnosis given as follows is based primarily on specimens from Russia, but also in comparison with the original description of C. hefeiensis. Our specimens agree very well with the description given by Xu & Liang, 1996 for Cosmolaelaps hefeiensis. The species is easily recognised by the long and thick setae of the dorsal shield (most setae long enough to reach well past the base of next posterior seta) (Fig. 1), j 1, z 1, Z 5 simple and without knob at their bases, j 1 apically bent (hook shaped) and Z 5 shorter than J 5 (J 5 ≈ 1.5 x Z 5) (Fig. 1); sternal setae short, at most reaching base of next setae (Figs 2, 3), soft opisthogastric cuticle bearing 16 pairs setae, Jv 4 – 5 and Zv 4 – 5 thickened (Figs 2, 4), post-anal seta slightly thicker and longer than para-anal setae (Figs 2, 4), fixed digit of chelicera of female with six teeth, including three large proximal teeth (posterior to pilus dentilis) (Fig. 5), spatulate seta on legs absent, genu and tibia of leg I without conspicuously thickened seta (Figs 6, 7).