Caridina propinqua De Man, 1908b , p 227 Caridina propinqua : Kemp 1915 , p 309 Bouvier 1925 , p 181 Johnson 1961 , p131 De Silva 1982 , p 127 Ng and Choy 1990 , p 17 Shokita 2005c , p 216 Shokita et al. 2002a , p 88 Shokita et al. 2003a , p 101 Caridina blancoi Chace 1997 , p 7 Caridina hainanensis Liang and Yan, 1983 , p 211 Caridina hainanensis : Liang 2004 , p 302 Atyid shrimps (Crustacea: Decapoda: Caridea) of the Ryukyu Islands, southern Japan, with descriptions of two new species Cai, Y. Journal of Natural History 2006 2006-12-25 40 38 - 40 2123 2172 8V758 De Man, 1908 De Man 1908 [431,874,884,908] Malacostraca Atyidae Caridina GBIF Animalia Decapoda 29 2150 Arthropoda species propinqua  ( Figures 10and 11)      Caridina propinqua  De Man, 1908b, p 227, pl 19, fig. 6 [ typelocality: Dhappa, near Calcutta, India].     Caridina propinqua: Kemp 1915, p 309; 1918, p 274;  Bouvier 1925, p 181, figs. 375, 381;  Johnson 1961, p131, figs. 12–15;  De Silva 1982, p 127, fig. 5;  Ng and Choy 1990, p 17; Shokita 2003, p 250, fig. 18D;  Shokita 2005c, p 216; 2006f, p 61;  Shokita et al. 2002a, p 88;  Shokita et al. 2003a, p 101.     Caridina blancoi  Chace 1997, p 7, fig. 2 [ typelocality: Tayabus River, Luzon Island Philippines].     Caridina hainanensis Liang and Yan, 1983, p 211, fig. 1 [Wenchang County, HainanIsland, China].     Caridina hainanensis: Liang 2004, p 302, fig. 148.   Material examined One male, cl 2.9 mm(USNM-264045, holotypeof  Caridina blancoi), near mouth of Tayabas River, Luzon Island, Philippines, 25 February 1909; 1 male, cl 2.2 mm(SHU-79-310-1, holotypeof  Caridina hainanensis),  1 female, cl 4.0 mm (SHU-79-310-2, paratypeof  C. hainanensis), Wenchang County, Hainan Island, China, coll. X. Liangand S. Yan,  14 April 1979; 11 males, cl 2.6–3.3 mm,  6 females, cl 3.5–3.8 mm, 16 ovigerous females, cl 3.4–4.0 mm, URB, mangrove of Nakama River, Iriomote Island, Ryukyu Islands, coll. S. Shokita,  3–5 June 1985;  30 specimens, ZRC 2004.0579, tide-pool in mouth of Shira River, Iriomote Island, Ryukyu Islands,  5 October 1982.  Figure 10.  Caridina propinqua. A, cephalothorax and cephalic appendages, lateral view; B, preanal carina; C, telson; D, distal portion of telson; E, diaeresis; F, scaphoceite; G, cephalothorax and cephalic appendages, lateral view; H, male first pleopodc; I, male second pleopod. Scales: A–C, F, G51 mm; D, E, H, I50.2 mm (A–F, female, cl 4.0 mm, URB; G–I, male, cl 2.8 mm, URB).  Figure 11.  Caridina propinqua. A, first pereiopod; B, second pereiopod; C, third pereiopod; D, dactylus of third pereiopod; E, fifth pereiopod; F, dactylus of fifth pereiopod. Scales: A–C, E50.5 mm; D, F50.2 mm (female, cl 4.0 mm, URB).  Diagnosis Rostrum ( Figure 10A, G) straight or sloping ventrally anteriorly, reaching near middle of second segment of antennular peduncle, to end of third segment. Rostral formula: 3–4+9–16/ 1–7/1–6(3–4), no apical teeth. Suborbital angle acute, distinctly separated from antennal spines; pterygostomian margin rounded. Preanal carina ( Figure 10B) with a spine. Telson ( Figure 10C, D) with three to four pairs of dorsal spines and small posteromedial projection, lateral pair of spines longer than intermedial pairs. Antennular peduncle long, subequal to carapace length. Stylocerite reaching 0.8 times length of basal segment of antennular peduncle. Scaphocerite ( Figure 10F) 4.0 times as long as wide. First pereiopod ( Figure 11A) with carpus 2.3 times as long as high, chela 2.5 times as long as broad, finger longer than palm. Second pereiopod ( Figure 11B) with carpus 6.8 times as long as high, chela 4.1 times as long as broad, fingers 2.0 times as long as palm. Third pereiopod ( Figure 11C, D) with propodus 3.2 times as long dactylus, propodus without enlargement. Dactylus ending in two claws, with one to four spines on flexor margin. Fifth pereiopod ( Figure 11E, F) with propodus 2.5 times as long as dactylus; dactylus ending in one claw, with 57–76 spinules on flexor margin. Endopod of male first pleopod with no appendix interna. Uropodal diaeresis with 13–19 spinules. Egg size: 0.38–0.48× 0.25–0.30 mm.  Habitat Lower reaches of rivers or mountain streams which discharge to the sea. Commonly found in mangrove creeks.  Remarks  Liang and Yan (1983)described  Caridina hainanensison the basis of specimens from HainanIsland. Their species has the same typical characteristics as  C. propinqua,namely the form of the rostrum and the telson, the form of various pereiopods, especially the third, which has a very small number of spines (one to three in  C. hainanensisvs. one to four in  C. propinqua) on the flexor margin of the dactylus, the identical form of the endopod of male first pleopod. Re-examination of the typesindicated that  C. hainanensisshould be regarded as a junior synonym of  C. propinqua.  Chace (1997)proposed a new species, based on a single specimen. He commented that ‘‘(t)he proposal of a new species, based on a single specimen in a genus that is noteworthy for its variable species, may be questionable, but it seems desirable to call attention to a taxon that apparently differs from all others known in a combination of characters; the form and dentition of the rostrum and telson; the prominence of the suborbital angle; and the form of the chelae and carpi of two anterior pereiopods and of the dactyls of the third and fourth pereiopods.’’ Re-examination of the holotypeconfirms that it is identical with  C. propinqua. Egg size of this species is quite variable. It is 0.39–0.45× 0.24–0.27 mmin specimens from Hainan ( Liang and Yan 1983), 0.54× 0.36 mmin populations from Malaysia( Johnson 1961) and 0.38–0.48× 0.25–0.30 mmin the present specimens from the Ryukyus. Kemp (1918)reported  C. propinquafrom southern Thailand. The identity of his species is doubtful as it had an egg size of 0.64–0.70× 0.39–0.44 mm, which is much larger than in specimens from elsewhere. This record has recently been reported by Shokita (2003). Previously,  Caridina propinquahas been reported from Sri Lanka( De Silva 1982), India( De Man 1908b; Kemp 1915), Malaysia( Johnson 1961; Ng and Choy 1990), southern China( Liang and Yan 1983) and the Philippines( Chace 1997).  Distribution  Sri Lanka, India, Malay Peninsula, Philippines, and China. [361,650,950,974] India Dhappa Calcutta 29 2150 1 [330,538,1144,1168] Island Philippines Tayabus River Luzon 29 2150 1 1979-04-14 X. Liang & S. Yan China Wenchang County Island 29 2150 1 1 Hainan paratype 1985-06-03 1985-06-05 1985-06-03 URB S. Shokita China Ryukyu Islands Nakama River Iriomote Island 29 2150 6 6 Hainan paratype 1982-10-05 ZRC China Ryukyu Islands Shira River Iriomote Island 29 2150 ZRC 2004.0579 30 Hainan paratype