Caridina elongapoda Liang & Yan, 1977

Shokita, Yixiong Cai Shigemitsu, 2006, Report On A Collection Of Freshwater Shrimps (Crustacea: Decapoda: Caridea) From The Philippines, With Descriptions Of Four New Species, Raffles Bulletin of Zoology 54 (2), pp. 245-270 : 249-250

Caridina elongapoda Liang & Yan, 1977

Caridina nilotica elongapoda Liang & Yan, 1977: 220 , Figs. 5-8 [type locality: Xinzai , Gulei village, Zhangpu County, Fujian, southern China].

Caridina aff. brachydactyla - Yeo, Cai & Ng, 1999: 218, Figs. 10- 14.

Caridina longirostris - Chace, 1997: 14 (part), Fig. 6 .

Material examined. – 4 ovig. females, cl. 6.3-8.5 mm, 1 female, cl 4.4 mm, 3 males, cl 4.1-4.4 mm, Malayas River , Victoria, Mindoro Island, Philippines, 14 Aug.1985 ; 3 males, cl 3.5-3.8 mm, 5 ovig. females, cl 4.0- 5.6 mm, Daakrongsod River , Cebu Island, Philippines, 28 Jul.1985 ; 2 males, cl 3.9-4.5 mm, 10 females, cl 4.2-4.7 mm, 3 ovig. females, cl 6.3-7.5 mm, Tag Bariri , Palawan, Island, Philippines, 9 Aug.1985 ; 4 males, cl 3.9-4.2 mm, 4 ovig. females, cl 5.6-6.2 mm, Panitian River , upper stream, ca 30 km from river mouth, Palawan Island. Philippines, 6 Aug.1985 ; 5 males, cl 3.2-3.9 mm, 2 females, cl 3.4-5.2 mm, 3 ovig. females, cl 4.4-6.3 mm, 4 juv., Sta. Rosa, Luzon, Philippines, 15 Jul.1985 ; 1 female, cl 3.5 mm, 2 ovig. females, cl 4.8-5.2 mm, Sewaragan River , San Joaquin, Panay Island, Philippines, 19 Aug.1985 ; 6 males, cl 2.8- 3.7 mm, 3 ovig. females, cl 5.0- 5.6 mm, Bororo River , Luzon Island, Philippines, 16 Jul.1985 ; 4 males, cl 3.7-4.2 mm, 3 females, cl 4.4- 5.2 mm, 3 ovig. females, cl 4.4-5.0 mm, Caboroan , Luzon Island, Philippines, 15 Jul.1985 ; 4 males, cl 3.2-4.0 mm, 1 female, cl 4.2 mm, 5 ovig. females, cl 4.9-6.2 mm, Villaflor River , Mindoro Island, Philippines, 15 Aug.1985 ; 9 males, cl 3.9-4.4 mm, 2 females, cl 5.1-5.5 mm, 3 ovig. females, cl 4.8-5.6 mm, Papait River , St. 2, upper stream, Palawan Island, Philippines, 9 Aug.1985 ; 2 males, cl 4.3-4.4 mm, 4 ovig. females, cl 5.5-6.2 mm, Panibacan River , Palawan Island, Philippines, 6 Aug.1985 ; 1 male, cl 2.9 mm, 1 female, cl 3.6 mm, 2 ovig. females, cl 4.3-6.2 mm, Aninoan River , Mindoro Island, Philippines, 15 Aug.1985 ; 3 males, cl 3.3-3.6 mm, 4 females, cl 2.7-3.4 mm, 1 ovig. female, cl 5.0 mm, Mabuhay River , Mindanao Island, Philippines, 25 Jul.1985 ; 8 males, cl 2.6-4.8 mm, 1 ovig. female, cl 4.8 mm, Santacruz River , Palawan Island, Philippines, 9 Aug.1985 ; 3 males, 5 females, Naguilian River , Luzon, Philippines, 14 Jul.1985 ; 1 ovig. female, cl 5.3 mm, Iraan River , Philippines, 5 Aug.1985 .

Comparative material examined. – 2 males, cl 3.8-4.1 mm, IZAS, Minjiang River , Fuzhou, Fujian Province, China, no date ; 6 males, cl 3.3-3.9 mm, 8 females, cl 3.6-5.5 mm, ZRC, Nan’ao County, Guangdong Province, China, coll. Y. Cai, Nov.1998 ; 2 males, cl 3.3 mm, USNM, Tilig , Lubang Island, Mindoro Occidental, Philippines, Albatross Philippine Expedition, 14 Jul.1908 .

Diagnosis. – Rostrum horizontal or slightly upturn at distal half, reaching to end of antennular peduncle, or slightly beyond distal end of scaphocerite; rostral formula: 2-3+16- 22+1-3/7-13. Antennal spine lower than inferior orbital angle. Pterygostomian margin rounded. Sixth abdominal somite 0.6 times as long as carapace length, 1.9 times as long as fifth somite, slightly shorter than telson. Telson 3.0 times as long as wide, terminating in a posteromedian projection, with 4 pairs of dorsal spinules and one pair of dorsolateral spinules; distal margin with 3-4 pairs of spines, lateral pair of posterior spines longer than intermedian pairs. Preanal carina triangular, without spine. Antennular peduncle 0.9 times as long as carapace; scaphocerite 4.0 times as long as wide. First pereiopod with merus as long as carpus, 2.5-2.6 times as long as wide; carpus 1.7-2.2 times as long as high; chela 1.9-2.1 times as long as broad, with fingers 1.0-1.8 times as long as palm. Second pereiopod with merus shorter than carpus, 5.4 times as long as wide; carpus 5.5 times as long as high. Third pereiopod with propodus 12 times as long as wide, 4.0 times as long as dactylus; dactylus of third pereiopod 3.1 times as long as wide, with 4-7 accessory spines along flexor margin. Fifth pereiopod with propodus 12 times as long as wide, 4.0 times as long as dactylus; dactylus 3.0 times as long as wide (spinules inluded), with 36-47 denticulate spinules along flexor margin. Endopod of male first pleopod triangular, with an elongated appendix at its distal end. Appendix masculina of male second pleopod reaching to half length of endopod. Uropodal diaeresis with 12-14 movable spinules. Eggs 0.38- 0.42 x 0.20-0.25 mm in diameter.

Remarks. – Caridina elongapoda is most similar to C. brachydactyla with respect to the form of rostrum, form of the pereiopods, notably the dactyli of the last three pereiopods, but differs by the distal spine on the posterior margin of propodus of third to fifth pereiopods which is not enlarged, and the form of first pereiopod, which has a short carpus (1.7 to 2.0 times as long as broad vs. 2.1 to 2.5 times) and short fingers (1.0 to 1.8 times as long as palm vs. 2.0 to 2.5 times). Reexamination of the specimens reported from Pulau Tioman, Peninsular Malaysia by Yeo et al (1999) under the name of Caridina aff. Brachydactyla shows that they should correctly be referred to the present species. According to the drawings of Chace (1997: figure 6), part of his Caridina longirostris specimens should be referred to current species too. According to an on going revision on the Caridina nilotica species group, C. longirostris does not have an appendix interna on the endopod of male first pleopod (Y. Cai pers. observ.). This is a new record for Philippines.

Distribution. – China, Malaysia, Philippines.

Figures

Fig. 5. Caridina palawanensis, new species, ovig. females, cl 4.1 mm, paratype, ZRC, Panitian River, upper stream, ca 30 km from river mouth, Palawan Island Philippines:A, cephalothorax and cephalic appendages, lateral view; B, telson;C, distal portion of telson;D, scaphocerite; E, first pereiopod; F, second pereiopod; G, third pereiopod; H, dactylus of third pereiopod; I, fifth pereiopod; J, dactylus of fifth pereiopod; K, preanal carina; L, uropodal diaeresis. Scale bars: A, B, D = 1 mm; E-G, I, K = 0.5 mm; C = 0.2 mm; H, J = 0.1 mm.

Fig. 6. Caridina palawanensis, new species, male, cl 2.8 mm, ZRC, Panitian River, upper stream, ca 30 km from river mouth, Palawan Island, Philippines: A, male second pleopod; B, male first pleopod. Caridina sumatrensis, male, cl 3.2 mm, ZRC, Santacruz River, Palawan Island, Philippines: C, cephalothorax and cephalic appendages, lateral view; D, first pereiopod; E, second pereiopod; F, third pereiopod; G, preanal carina. Potamalpheops miyai, male, cl 3.0 mm, ZRC, Surigao mangrove, Mindanao Island, Philippines:H, cephalothorax and cephalic appendages, lateral view; I, second pereiopod; J, propodus and dactylus of third pereiopod; K, fifth pereiopod; L, uropodal diaeresis. Scale bars: A, B = 0.2 mm, C, H = 1 mm, D-G, I-L = 0.5 mm.

Fig. 7. Caridina mindanao, new species, ovig. female, cl 3.8 mm, Mindanao, Philippines: A, cephalothorax and cephalic appendages; B, abdomen and telson; C, scaphocerite; D, mandible; E, maxillula; F, maxilla; G, first maxilliped; H, second maxilliped. Scale bars: A, B = 1 mm; C, H = 0.5 mm.

Fig. 8. Caridina mindanao, new species, ovig. female, cl 3.8 mm, Mindanao, Philippines: A. telson; B, distal portion of telson; C, first pereiopod; D, second pereiopod; E, third pereiopod; F, dactylus of third pereiopod; G, fifth pereiopod; H, dactylus of fifth pereiopod; I, third maxilliped; J, diaeresis. Scale bars: A, C-E, G, I = 0.5 mm; B, F, H = 0.1 mm; J = 0.2 mm.