Diacyclops pseudosuoensis, Karanovic, Tomislav, Grygier, Mark J. & Lee, Wonchoel, 2013

Karanovic, Tomislav, Grygier, Mark J. & Lee, Wonchoel, 2013, Endemism of subterranean Diacyclops in Korea and Japan, with descriptions of seven new species of the languidoides-group and redescriptions of D. brevifurcus Ishida, 2006 and D. suoensis Ito, 1954 (Crustacea, Copepoda, Cyclopoida), ZooKeys 267, pp. 1-76 : 34-35

Diacyclops pseudosuoensis sp. n.

Diacyclops languidoides suoensis Ito - Ito 1957: p. 15, Figs 35-44, 46-48. Synonymy. [partim.]

Diacyclops languidoides suoensis Ito - Ito 1957: p. 15, fig. 45. [non]

Diacyclops languidoides suoensis n. subsp. - Ito 1954: p. 399, Figs 114-148. [non]

Diacyclops suoensis Ito - Ueda et al. 1996: p. 309, fig. 4; Lee et al. 2007: p. 162, Figs 7-8; Chang 2009: p. 478, Figs 263-264. [non]

Type locality.

Japan, Kagoshima prefecture, Amami-Oshima island, Amami city, Naze High School, approximately 28°22'N, 129°29'E, well with a pump.

Type material.

Holotype female (illustrated by Ito (1957): Figs 46-48), allotype male from type locality, and 10 paratype females from type locality originally deposit ed at the Limnological Laboratory, Faculty of Fisheries, Prefectural University of Mie, Tsu city, Mie Prefecture, Japan (however, many administrative changes since original deposition made current location of types impossible to determin); all collected 12 August 1954, leg. Y. Morimoto. [not examined]

Additional paratype male deposited at the Limnological Laboratory, Faculty of Fisheries, Prefectural University of Mie, Japan; collected from Japan, Kagoshima prefecture, Amami-Oshima island, Amami city, Naze township, approximately 28°22'N, 129°29'E, well with a pump; 19 August 1954, leg. Y. Morimoto. [not examined]

Etymology.

The species name is composed of the Greek noun pseudos (= lie) prefixed to the existing specific name suoensis. The new name refers to the assumed close relationship between these two congeners.

Description.

Female and male as described in Ito (1957) from Amami-Oshima, and illustrated in his figures 46-48 as Diacyclops languidoides suoensis Ito, 1954.

Remarks.

This species is most similar to Diacyclops suoensis but can be distinguished by the longer innermost terminal caudal setae, which are slightly longer than the outermost terminal caudal ones, as well as by the longer apical endopodal spines on the fourth leg. Both species share very long dorsal caudal setae, which are about twice as long as the caudal rami and thus unique in the languidoides-group. Although the original description of Diacyclops suoensis by Ito (1954) was brief, after our redescription of it herein based on the Lake Biwa material (see above), we can confirm that it and Diacyclops pseudosuoensis sp. n. share many other morphological features. Among these are the armature formula of all swimming legs, similar proportions of the caudal rami, and similar proportions of the segments and armature of the fifth leg. Unfortunately, Ito (1957) did not describe or illustrate the antenna or mouth appendages, and he illustrated only the segments (without armature elements) of the antennula, so these features cannot be compared. Note that Ito (1957: fig. 45) provided a drawing of the female genital double-somite that is actually taken from his earlier publication ( Ito 1954) and does not pertain to the Amami-Oshima population.

As mentioned above, Diacyclops parasuoensis and Diacyclops suoensis are very similar to Diacyclops pseudosuoensis and Diacyclops hisuta sp. n., but probably only remotely related to Diacyclops ishidai sp. n., Diacyclops brevifurcus , Diacyclops leeae sp. n., Diacyclops hanguk sp. n.,and Diacyclops parahanguk sp. n.