Caridina sarasinorum Schenkel, 1902

Rintelen, Kristina von & Cai, Yixiong, 2009, Radiation Of Endemic Species Flocks In Ancient Lakes: Systematic Revision Of The Freshwater Shrimp Caridina H. Milne Edwards, 1837 (Crustacea: Decapoda: Atyidae) From The Ancient Lakes Of Sulawesi, Indonesia, With The Description Of Eight New Species, Raffles Bulletin of Zoology 57 (2), pp. 343-452 : 439-442

Caridina sarasinorum Schenkel, 1902

( Figs. 58–59 ; Table 23)

Caridina sarasinorum Schenkel, 1902: 492 , pl. 8, Figs. 2 a-e, 4a (type locality: Lake Poso).

Caridina sarasinorum – Chace, 1997: 19; Cai & Wowor, 2007: 315, fig. 3; von Rintelen et al., 2007a: 1033, fig. 2, Tables 1-2, 2008: 2244, Table 1.

Caridina Sarasinorum – Roux, 1904: 551; Bouvier, 1905: 73, 1913b: 182, 1925: 168, Figs. 356-359.

Material examined. – Lectotype: ovigerous female (cl 3.1 mm) ( NHMB 2 a), Indonesia, Sulawesi, Lake Poso , coll. Sarasin, no date indicated.

Paralectotypes – 4 males (cl 2.6-2.9 mm), 6 females (cl 2.7-3.4 mm) ( NHMB 2 a), data same as lectotype .

Others: Lake Poso: 3 ex. ( ZMB 29068), south shore, Pendolo beach at Hotel Mulia, 02°3.928'S, 120°41.536'E, loc. 157-04, on wood, coll. K . & T. von Rintelen, 15 Aug.2004 ; 2 ex. ( ZMB 29137), east shore, 01°59.867'S, 120°41.238'E, loc. 160-04, on mixed substrate, coll. K . & T. von Rintelen, 16 Aug.2004 ; 12 ex. ( ZMB 29201a, n=6; ZMB 29201b, n=1, and MZB Cru 1732, n=5), east shore, south of Cape Sinampada, 02°56.25'S, 120°40.443'E, loc. 159-04, ( ZMB a) on leaf litter, ( ZMB b and MZB) on wood, coll. M. Glaubrecht & T. von Rintelen, 30Mar.2004 ; 7 ex. ( ZMB 29261, some SEM material), east shore, Cape Watulunto , 02°0.825'S, 120°42.007'E, loc. 63-04, on leaf litter, coll. M. Glaubrecht & T. von Rintelen, 30 Mar.2004 ; 17 ex. ( MZB Cru 1733, n=9; ZMB 29288, n=8), east shore, 02°0.825'S, 120°42.007'E, loc. 161-04, on wood, coll. K. von Rintelen, 16 Aug.2004 ; 13 ex. ( MZB Cru 1734, n=6; ZMB 29383, n=7), west shore, Siuri, 01°48.259'S, 120°31.667'E, loc. 186-05, on mixed substrate, coll. K. von Rintelen, 6 Oct.2005 ; 5 ex. ( ZMB 29386), west shore, 02°2.734'S, 120°37.368'E, loc. 178-05, on wood, coll. K. von Rintelen, 6 Oct.2005 ; 11 ex. ( MZB Cru 1735, n=6; ZMB 29388, n=5, some SEM material), east shore, at road Tentena-Peura, 01°47.33'S, 120°38.079'E, loc. 160-05, on wood, coll. K. von Rintelen, 3 Oct.2005 ; 14 ex. ( MZB Cru 1736, n=7; ZMB 29402, n=7, some SEM material), west shore, 01°52.205'S, 120°32.281'E, loc. 184-05, on macrophytes, coll. K. von Rintelen, 6 Oct.2005 ; 15 ex. ( MZB Cru 1737, n=8; ZMB 29403, n=7), east shore, shallow bay, 01°49.702'S, 120°38.161'E, loc. 159-05, on macrophytes, coll. K. von Rintelen, 3 Oct.2005 ; 1 ex. ( ZMB 29406), west shore, Taipa , 01°55.289'S, 120°32.77'E, loc. 182-05, on wood, coll. K. von Rintelen, 6 Oct.2005 .

Description. – Carapace length 2.6-3.6 mm (n=12). Rostrum ( Fig. 59A ; Table 23) long, reaching beyond end of scaphocerite, 1.0-1.2 times as long as carapace (n=8), armed dorsally with 15-21 teeth (including 4-6 teeth posterior to orbital margin), approx. anterior third to half unarmed, without subapical teeth, armed ventrally with 8-14 teeth. Antennal spine situated below inferior orbital cl (mm) 2.6-3.6 3.1 ± 0.3 3.1 12 rl / cl 1.0-1.2 1.1 ± 0.1 1.1 8 n dorsal rostral teeth 15-21 18 ± 2 17 8 n ventral rostral teeth 8-14 12 ± 2 13 8 abds6 / cl 0.6-0.8 0.7 ± 0.1 0.7 11 abds6 / abds5 1.7-2.0 1.9 ± 0.1 1.9 11 abds6 / h tel 0.9-1.0 0.9 ± 0.1 1.0 6 h tel / w tel 3.2-3.6 3.4 ± 0.2 3.3 5 n spines uropodal diaeresis 8-10 9 ± 1 9 5 h ch1 / w ch1 1.9-2.0 1.9 ± 0.1 1.9 8 h ch1 / h ca1 1.3-1.5 1.5 ± 0.1 1.5 9 h ca1 / w ca1 1.1-1.9 1.7 ± 0.3 1.7 8 h ch2 / w ch2 2.2-2.9 2.5 ± 0.2 2.6 8 h ch2 / h ca2 0.8-0.9 0.8 ± 0.1 0.8 9 h ca2 / w ca2 3.6-5.0 4.4 ± 0.5 4.6 8 n spines p3 6-7 7 ± 0 7 5 n spines p5 33-43 39 ± 4 39 5

angle. Pterygostomial angle broadly rounded. Eyes well developed, anterior end 0.5-0.6 times length of basal segment of antennular peduncle (n=5). Antennular peduncle 0.9-1.1 times as long as carapace (n=5), second segment 1.7-2.0 times length of third segment, third segment 0.3-0.4 times length of basal segment. Stylocerite reaching 0.9-1.0 times length of basal segment of antennular peduncle (n=5). Scaphocerite ( Fig. 59D ) 3.8-4.4 times as long as wide (n=5).

Sixth abdominal somite 0.6-0.8 times length of carapace (n=11), 1.7-2.0 times as long as fifth somite (n=11), 0.9- 1.0 times length of telson (n=6). Telson ( Fig. 59C,H,K ) 3.2-3.6 times as long as wide (n=5), distal margin rounded, without projection, with 3-4 pairs of spinules and 1 pair of dorsolateral spinules; distal end with 3 pairs of spines, lateral pair sometimes but not always longer than intermediate pairs. Preanal carina ( Fig. 59E ) with a spine. Uropodal diaeresis ( Fig. 59B ) with 8-10 movable spinules (n=5).

5 pairs of pleurobranchs well developed; 3 pairs of arthrobranchs, 2 on third maxillipeds, with second pair strongly reduced in size, 1 pair on first pereiopod; 1 pair of podobranchs on second maxilliped reduced strongly to a laminate form. Epipods present on first pereiopod, greatly reduced or absent from second pereiopod. Mouthparts as described by Cai & Wowor (2007).

Chela and carpus of first pereiopod distinctly stouter and broader than chela and carpus of second pereiopod ( Fig. 59 L-N); chela of first pereiopod 1.9-2.0 times as long as wide (n=8), 1.3-1.5 times length of carpus (n=9); tips of fingers rounded, without hooks; dactylus 0.9-1.1 times as long as palm (n=5); carpus 1.1-1.9 times as long as wide (n=8), 1.0-1.2 times length of merus (n=5). Chela of second pereiopod 2.2-2.9 times as long as wide (n=8), 0.8-0.9 times length of carpus (n=9); tips of fingers rounded, without hooks, dactylus 0.9-1.4 times as long as palm (n=5); carpus 3.6-5.0 times as long as wide (n=8), 1.3-1.5 times as long as merus (n=5).

Third pereiopod ( Fig. 59G,I ) slender, dactylus 3.3-4.5 times as long as wide (terminal spine included, without spines of flexor margin; n=5), terminating in one large claw with 6-7 accessory spines on flexor margin; propodus 9.3-11.7 times as long as wide, 2.9-4.1 times as long as dactylus; carpus 4.1-5.0 times as long as wide, 0.6-0.7 times as long as propodus, 0.5-0.6 times as long as merus; merus 6.8-8.9 times as long as wide, bearing 3-4 strong, movable spines on posterior margin of outer surface.

Fifth pereiopod slender ( Fig. 59F,J ), dactylus 4.0-5.6 times as long as wide (terminal spine included, without spines of flexor margin; n=5), terminating in one large claw with 33- 43 accessory spines on flexor margin; propodus 10.0-16.0 times as long as wide, 2.6-3.2 times as long as dactylus; carpus 4.3-5.7 times as long as wide, 0.5-0.6 times as long as propodus, 0.6 times as long as merus; merus 6.3-7.8 times as long as wide, bearing 2-3 strong, movable spines on posterior margin of outer surface.

Endopod of male first pleopod ( Fig. 59O ) elongated triangular, 1.9-2.5 times as long as proximally wide (n=5), without appendix interna. Appendix interna of male second pleopod ( Fig. 59P ) 0.8-0.9 times length of appendix masculina (n=5).

Ovigerous females with 19- 23 eggs (n= 2 females); egg size 0.9-1.0 x 0.5-0.6 mm (n=20, eggs with and without eyes).

Figures

Fig. 58. Distribution of Caridina sarasinorum in Lake Poso.

Fig. 59. Caridina sarasinorum from Lake Poso. A. Cephalothorax and cephalic appendages, female (ZMB 29388); B. Uropodal diaeresis, male (ZMB 29402); C. SEM image of telson and uropods, female (ZMB 29388); D. Scaphocerite, female (ZMB 29403); E. Preanal carina, F. Fifth pereiopod, female (ZMB 29388); G. Third pereiopod; H. Telson; I. Dactylus of third pereiopod; J. Dactylus of fifth pereiopod; K. Distal end of telson; L. SEM image of chela and carpus of first and second pereiopods; M. First pereiopod; N. Second pereiopod; O. Endopod of male first pleopod (ZMB 29403); P. Appendix masculina of male second pleopod. Scale bars: A, D = 1.0 mm; C, E-H, L-P = 0.5 mm; B, I-K = 0.1 mm.

Fig. 2. General morphology of Caridina (modified from Holthuis, 1955: 3; shrimp drawing modified from Woltereck, 1937a: 215).