Caridina linduensis Roux, 1904

Wowor, Daisy, 2015, The atyid shrimps from Lake Lindu, Central Sulawesi, Indonesia with description of two new species (Crustacea: Decapoda: Caridea), Zootaxa 3957 (5), pp. 501-519 : 502-506

publication ID	https://doi.org/ 10.11646/zootaxa.3957.5.1
publication LSID	lsid:zoobank.org:pub:2AF44C7D-302B-4C4D-8B89-9ABB90E50AE8
DOI	https://doi.org/10.5281/zenodo.6112499
persistent identifier	https://treatment.plazi.org/id/B36387EF-AA0D-FFD5-818F-DEEF66A0FA5E
treatment provided by	Plazi
scientific name	Caridina linduensis Roux, 1904
status

Treatment

Caridina linduensis Roux, 1904 View in CoL

( Figs. 1–2 View FIGURE 1 View FIGURE 2 , 8 View FIGURE 8 A)

Caridina linduensis J. Roux 1904: 541 View in CoL , pl. 9, figs. 1–4 [type locality: Lake Lindu, Sulawesi (Celebes) , Indonesia].— Bouvier 1925: 224, figs. 497–503.— Chace 1997: 13.—von Rintelen et al. 2008: 2244.— De Grave & Fransen 2011: 276.

Material examined. Four males, cl 3.0– 3.3 mm, 9 females, cl 3.6–4.4 mm, 6 ovigerous females, cl 3.8–4.2 mm ( MZB Cru 3793), Uwe Rawa at the outlet of Lake Lindu, about 50 m from the lake, 01°16’20.1”S 120°06’32.7”E, on leaf litter and dead wood, coll. Annawaty & D. Wowor, 13 Nov 2011; 1 male, 1 ovigerous female ( ZRC), same data as MZB Cru 3793; 7 males, cl 2.7–3.4 mm, 4 females, cl 3.5–4.1 mm, 5 ovigerous females, cl 3.8–4.2 mm, 1 male, cl 3.5 mm, dissected ( MZB Cru 3794), southwest coast of P. Bola, 01°20’52.3”S 120°03’51.2”E, on root of macrophytes, coll. Annawaty & D. Wowor, 17 Nov 2011; 5 males, cl 3.3–3.5 mm, 4 females, cl 3.8–4.7 mm, 5 ovigerous females, cl 4.0– 4.9 mm, 1 female, cl 3.8 mm, dissected ( MZB Cru 3795), at the mouth of Uwe Langko, 01°20’38.1”S 120°03’32.6”E, on root of macrophytes, coll. Annawaty & D. Wowor, 17 Nov 2011; 2 males, cl 3.0– 3.3 mm, 2 females, cl 3.9–4.0 mm ( MZB Cru 3796), at Tomado beach, 01°19’31.9”S 120°03’10.0”E, on root of macrophytes, coll. Annawaty & D. Wowor, 15 Nov 2011.

Description. Rostrum slender, reaching near or slightly beyond end of third segment of antennular peduncle, not overreaching end of scaphocerite, tip of rostrum straight or slightly curved upwards, 0.5–0.7 times as long as carapace, dorsal margin horizontal or slightly sinuous, dorsal with 7–12 (mode 9) teeth, about one-third distal unarmed, no tooth behind orbital margin nor sub-apical tooth, ventral with 0–6 (mode 2 or 3) teeth. Antennal spine short, situated below inferior orbital angle. Pterygostomian margin rounded ( Fig. 1 View FIGURE 1 A–C).

Eyes well developed, anterior end 0.6 times length of basal segment of antennular peduncle. Antennular peduncle 0.6–0.8 times as long as carapace, basal segment of antennular peduncle longer than second, third segment lengths, second segment distinctly longer than third segment, anterolateral angle of basal segment reaching 0.3–0.5 proximal of second segment of antennular peduncle ( Fig. 1 View FIGURE 1 E). Stylocerite reaching 0.7 of basal segment of antennular peduncle. Scaphocerite 3.2 times as long as wide ( Fig. 1 View FIGURE 1 D).

Incisor process of mandible ending in 16–18 irregular teeth, molar process truncated ( Fig. 1 View FIGURE 1 F–G). Lower lacinia of maxillula broadly rounded, upper lacinia elongated, with numerous distinct teeth on inner margin, palp slender ( Fig. 1 View FIGURE 1 H). Upper endite of maxilla subdivided, palp short, scaphognathite tapering posteriorly with numerous long, curved setae at posterior end ( Fig. 1 View FIGURE 1 I). Palp of first maxiliped ending in triangular projection ( Fig. 1 View FIGURE 1 G). Podobranch of second maxiliped reduced to lamina ( Fig. 1 View FIGURE 1 K). Third maxiliped reaching end of scaphocerite, with ultimate segment slightly longer than penultimate segment ( Fig. 1 View FIGURE 1 L).

Epipod present on first 2 pereiopods, reduced in size posteriorly, absent on last 3 pereiopods. Chela and carpus of first pereiopod distinctly stouter, broader than chela and carpus of second pereiopod.

First pereiopod stout, reaching to distal end of basal segment of antennular peduncle; merus 1.8–2.7 times as long as wide, slightly shorter than carpus; carpus excavated anteriorly, 1.6–2.4 times as long as wide, shorter than chela, chela 2.1–2.9 times as long as wide; movable finger as long as or slightly longer than palm, finger tip round ( Fig. 2 View FIGURE 2 A).

Second pereiopod reaching to distal end of third segment of antennular peduncle; merus distinctly shorter than carpus, 4.4–5.8 times as long as wide; carpus slender, 5.1–6.9 times as long as wide, 1.2–1.3 times length of chela; chela 2.5–3.7 times as long as wide; movable finger 1.2–1.8 times as long as palm, finger tip round ( Fig. 2 View FIGURE 2 B).

Third pereiopod slender, dactylus, half distal propodus overreach third segment of antennular peduncle; propodus 10.4–13.0 times as long as wide, 4.1–4.5 times as long as dactylus; dactylus 2.8–4.0 times as long as wide (terminal spine included, without spines of flexor margin), terminating in 1 large claw with 5–9 (mode 5) accessory spines on flexor margin, reducing in size proximally ( Fig. 2 View FIGURE 2 C–D). Sexual dimorphism present. Third, fourth pereiopods of male with numerous hooked spinules on inner, outer margins of propodus, carpus, respectively.

Fifth pereiopod slender, tip of dactylus reach end third segment of antennular peduncle; propodus 10.8–13.7 times as long as wide, 2.5–3.3 times as long as dactylus; dactylus 4.7–5.8 times as long as wide (terminal spine included, without spines of flexor margin), terminating in 1 large claw, with 53–56 (mode 54) accessory spinules on flexor margin ( Fig. 2 View FIGURE 2 E–F).

Endopod of male first pleopod subrectangular, without appendix interna, 2.8 times as long as wide, 0.4 times length of exopod ( Fig. 2 View FIGURE 2 G).

Appendix masculina of male second pleopod very slender, 0.5–0.6 times length of endopod, with appendix interna 0.3–0.5 times length of appendix masculina ( Fig. 2 View FIGURE 2 H).

Sixth abdominal somite 0.5–0.6 times of carapace, 1.4–1.6 times as long as fifth somite, 0.9 times as long as telson. Telson 2.8 times as long as wide, distal margin rounded without posteromedian projection, with 4–6 (mode 5) pairs of dorsal spinules, 1 pair of dorsolateral spinules; distal end with 3 or 4 (mode 3) pairs of spine, lateral pair of spines distinctly longer than intermediate pairs ( Fig. 2 View FIGURE 2 I–J). Preanal carina sub-rectangular, without spine ( Fig. 2 View FIGURE 2 L).

Uropodal diaeresis with 14–16 (mode 16) movable spinules ( Fig. 2 View FIGURE 2 K).

Ovigerous females with 26– 47 eggs (n = 3); Egg size 1.0–1.1 × 0.7 mm in diameter (n = 40, eggs with eyes).

Habitat. Caridina linduensis is dwell amongst leaf litter, roots of macrophytes and dead wood ( Fig. 9 View FIGURE 9 A). It mainly occurs in the lake but can also be found in the mouth of the only outlet stream with mud-sandy substrates and very slow currents or almost stagnant water. The water temperature varies between 28.0°and 29.0°C.

Distribution. Caridina linduensis is found only in Lake Lindu and the mouth of outlet stream. It is distributed in the south and southwestern of the lake, and around the junction of the lake and Uwe Rawa at the north. Four specimens were also caught at the west coast of the lake at Tomado village ( Fig. 7 View FIGURE 7. A ).

Remarks. Although we did not compare our specimens with the type material of Caridina linduensis , but excellent drawings of the type material are given in the unpublished thesis of Cai (2004) which confirms our observations that our collected specimens from the type locality are indeed C. linduensis . However, our material has few differences from those examined by Roux (1904) in the higher number of accessory spines on the flexor margin of the fifth pereiopods (53–56, mode 54 versus 50) and the ratio of the dactylus to the palm of the first pereiopod (dactylus as long as or slightly longer than palm versus dactylus slightly shorter than palm). The differences might be an intraspecific variation within the population.

In this study, we observe two characters that were not mentioned by Roux (1904), i.e., the mandible and the presence of sexual dimorphism in C. linduensis . The results show that the terminal of the incisor process of the mandible end in many irregular sharp teeth, and the inner margin of the propodus and the outer margin of the carpus of both third and fourth pereiopods of males are covered by numerous claw-shape spinules.

With regards the shape of the rostrum, the position of the antennal spine in relation to the inferior orbital angle, and the absence of the posteromedian projection of the telson, C. linduensis resembles C. sarasinorum and C. schenkeli , two endemic Caridina species from Lake Poso in Sulawesi . However, it can be separated from both species by the absence of tooth behind the orbital margin (vs. 3–7 teeth in C. sarasinorum , 2–5 teeth in C. schenkeli ), the lower number of the ventral rostral teeth (0–6 teeth versus 8–17 teeth in C. sarasinorum , 9–13 teeth in C. schenkeli ), the smaller ratio of the second segment to the third segment of the antennular peduncle (1.0–1.3 versus 2.0 in C. sarasinorum , 1.6–2.0 in C. schenkeli ), the smaller ratio of the antennular peduncle length to the carapace length (0.6–0.8 times versus as long as in C. sarasinorum , 0.8–1.0 times in C. schenkeli ), the relatively broader scaphocerite (3.2 times as long as wide versus 4.4 times in C. sarasinorum , 3.3–4.7 times in C. schenkeli ), the more slender dactylus of the fifth pereiopod (4.7–5.8 as long as wide versus 3.0– 3.9 in C. sarasinorum , 3.7–4.8 in C. schenkeli ), the broader telson (2.8 times as long as wide versus 4.1 times in C. sarasinorum , 3.0–3.6 times in C. schenkeli ), the smaller ratio of the sixth abdominal somite to the fifth abdominal somite (1.4–1.6 versus 2.0 in C. sarasinorum , 1.9–2.0 in C. schenkeli ), the absence of preanal carina spine (vs. with spine in both C. sarasinorum and C. schenkeli ), and the higher number of the uropodal diaresis spinules (14–16 versus 8–10 in C. sarasinorum , 10–11 in C. schenkeli ). Caridina linduensis can also be separated from C. sarasinorum and C. schenkeli by the number of the accessory spinules on the flexor margin of the fifth pereiopod (53–56 versus 33–43 in C. sarasinorum , 57–64 in C. schenkeli ), and the different shape of the endopod of the first pleopod of male (subrectangular in C. linduensis , versus sub-triangular in C. sarasinorum , elongated triangular in C. schenkeli ).

Caridina linduensis also shares several characters with C. schenkeli which can be used to distinguished both species from C. sarasinorum , i.e., by the presence of epipod on the first two pereiopods (vs. present on the first pereiopod and greatly reduced or absent on the second pereiopod in C. sarasinorum ), and the larger egg size (1.0– 1.1 × 0.7 mm versus 0.9–1.0 × 0.5–0.6 mm in C. sarasinorum ). Caridina linduensis can also be distinguished from C. schenkeli by the smaller ratio of the appendix interna to the appendix masculina of the male second pleopod (0.3–0.5 versus 0.7–0.8 in C. schenkeli ) and from C. sarasinorum by the lower number of the dorsal rostral teeth (7–12 teeth versus 12–19 teeth in C. sarasinorum ).