Parapeneopsis venusta De Man, 1907

Hsu, Yen-Cheng & Chan, Tin-Yam, 2023, On the penaeid shrimps of the genus Parapenaeopsis Alcock, 1901 (Crustacea, Decapoda) from Taiwan, Zootaxa 5361 (2), pp. 221-236 : 231-233

Parapeneopsis venusta De Man, 1907

( Figs. 5 , 6f )

Parapeneopsis venusta De Man, 1907: 134 (type locality: Indonesia); Hall 1961: 95, pl. 18- 9, 10; 1962: 27, figs 106, 106a, b.

Parapenaeopsis venusta — De Man 1911: 93, pl. 9-fig. 30, 30a–c; Perez Farfante & Kensley 1997:121; Lee et al. 1999: 446.

Batepenaeopsis venusta — Sakai & Shinomiya 2011: 496; De Grave & Fransen 2011: 213; Shinomiya & Sakai 2016: 507: figs 6–7.

Material examined. Yilan County, Dasi fishing port, 28 Apr 1989, 1 male cl 13.6 mm ( NTOU M02394 ) . Tainan City, Shalun , station A2, 19 Aug 2011, 1 female cl 5.0 mm ( NTOU M02496 ) . Penghu County, Magong fishing port, 17 Apr 2019, 6 females cl 10.7–17.3 mm ( NTOU M02395 ) .

Diagnosis. Rostrum with 7–9 dorsal teeth other than epigastric tooth; horizontal and with ventral margin concave, short and only more or less reaching tip of proximal segment of antennular peduncle. Longitudinal suture short and extending posteriorly to about level of epigastric tooth. Only pereiopod I bearing basial spine, pereiopods I and II without epipods.Abdominal somites I and II lacking dorsal carina. Telson often with minute movable lateral spinules but sometimes unarmed. Males with endopod of pleopod II normal; petasma with distomedian projection minute, distolateral projection divided into two processes, distal process semicircular and flap like, proximal process triangularly elongate and directed proximolaterally. Female thelycum with anterior plate spade like and bearing spine-like tip, posterior part with median longitudinal groove; posterior plate with median longitudinal groove continuous with that of anterior plate.

Coloration. Body whitish translucent and covered with brownish red patches and dots. Eyes dark gray. Abdominal somites somewhat with whitish posterior margin and bearing large brownish spot on each of pleura I–V. Uropods of tail-fan reddish with distal parts of exopods whitish.

Distribution. Widely distributed in the Indo-West Pacific from Thailand to Taiwan and Northern Australia, at depths of 11–44 m ( Pérez Farfante & Kensley 1997; Chan 1998).

Remarks. Like P. tenella , this small species is uncommon in Taiwan. Although the general appearances and coloration of P. venusta and P. tenella are rather similar, they can be readily separated by the following characters. Parapenaeus venusta has a epigastric tooth but short longitudinal suture ( Fig. 5a ), while P. tenella lacks epigastic tooth and bearing long longitudinal suture ( Fig. 4a ). The shape of the petasma and thelyum are also distinctly different between these two species. The distolateral projection of the petasma lack the additional distal flap-like process in P. tenella ( Fig. 4b vs. 5b). The thelycum of P. tenella has the anterior plate lacking a distal spine and the posterior plate only has the anterior half notched and continuous with the median groove of the anterior plate ( Fig. 4c ). In P. venusta , the thelycum has the anterior plate bearing a distinct distal spine and the median groove running nearly all the way onto the posterior plate ( Fig. 5c ).

The distribution of P. venusta is generally considered to be much more restricted than P. tenella and only extends west to Gulf of Thailand (Chan 1988). Rajakumaran & Vaseeharan (2014) reported P. venusta from India while Shinomiya & Sakai (2016) accepted this record. The Indian record of “ P. venusta ” is provided with a photograph by Rajakumaran & Vaseeharan (2014: fig. 4) but the photograph is clearly not P. venusta in being much large in size (body about 10 cm), rostrum with tip distinctly upturned, and greenish gray in body coloration (hence more similar to P. cornuta instead). On the other hand, Lee et al. (1999) listed P. venusta from Taiwan and adjacent areas, representing the northern most distribution of this species. However, the sampling stations of Lee et al. (1999: fig. 1) including many localities in the South China Sea, East China Sea and northwest of the Philippines far from Taiwan. The present work, therefore, formally records P. venusta from Taiwan for the first time.

Figures

FIGURE 4. Parapenaeopsis tenella (Bate, 1888), a, c, female cl 13.5 mm (NTOU M02393); b, male cl 9.5 mm (NTOU M02393). a, carapace and anterior appendages, lateral view. b, petasma, ventral view. c, thelycum, ventral view. Scales: a, 5 mm; b, 1 mm; c, 3 mm.

FIGURE 5. Parapeneopsis venusta De Man, 1907, a, c, female cl 15.7 mm (NTOU M02395); b, male cl 13.6 mm (NTOU M02394). a, carapace and anterior appendages, lateral view. b, petasma, ventral view. c, thelycum, ventral view. Scales: a, 5 mm; b, 1 mm; c, 3 mm.

FIGURE 6. a, Parapenaeopsis amicus V.C. Nguyên, 1971, female cl 29.5 mm (NTOU M02417). b, P. cornuta (Kishinouye, 1900), male cl 14.5 mm (NTOU M02357). c, P. hardwickii (Miers, 1878), female cl 30.3 mm (NTOU M02610). d, P. hardwickii (Miers, 1878), male (from Chan & Yu 1986, specimen lost). e, P. tenella (Bate, 1888), female cl 16.7 mm (NTOU M02392). f, P. venusta De Man, 1907, females cl 17.3 mm (NTOU M02395).