Caridina wenchangensis Hou, Zhang & Guo, 2025
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publication ID |
https://doi.org/10.3897/zse.101.172207 |
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publication LSID |
lsid:zoobank.org:pub:55065651-D7CD-46B2-AB9E-B53611DD38A5 |
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DOI |
https://doi.org/10.5281/zenodo.17651054 |
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persistent identifier |
https://treatment.plazi.org/id/2B6806B8-C144-5392-B32A-1E3C79838585 |
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scientific name |
Caridina wenchangensis Hou, Zhang & Guo |
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sp. nov. |
Caridina wenchangensis Hou, Zhang & Guo sp. nov.
Figs 2 C View Figure 2 , 7 View Figure 7 , 8 View Figure 8
Materials examined.
China – Hainan Island • Holotype: 1 ♂, cl 3.4 mm, ( FU 5713001 ), Wenchang City , 19°26'43"N, 110°34'39"E, al. 72 m, stn. 5, coll. WANG C. Y. and HOU J. J., 22 Jan. 2024 GoogleMaps .
Paratypes: 1 ♂, cl 2.6 mm, ( FU 5713002 ); 1 ♂, cl 2.7 mm, ( FU 5713003 ); 2 ♂♂, cl 2.7–2.9 mm, ( FU 5713005 ); 1 ♀, cl 3.1 mm, ( FU 5713004 ); 1 ovigerous ♀, cl 3.4 mm, ( FU 5713006 ), same collection data as holotype GoogleMaps .
Comparative material.
Caridina clinata Cai, Nguyen & Ng, 1999 . See this article. Caridina haivanensis Do & Dang, 2010 . Vietnam – Da Nang Prov. • 1 ♂, cl 4.4 mm, ( FU 55001 ); 1 ♂, cl 5.0 mm, ( FU 55002 ); 1 ♂, cl 4.2 mm, ( FU 55003 ); 2 ♂♂, cl 4.2–4.4, ( FU 55004 ); 1 ♀, cl 4.5 mm, ( FU 55005 ); 1 ♀, cl 5.3 mm, ( FU 55006 ); 1 ♀, cl 5.3 mm, ( FU 55007 ); 6 ♀♀, cl 4.1–5.2 mm, ( FU 55008 ), Tho Quang, 16°6'46"N, 108°15'25"E, al. 26 m, stn. 14, coll. HAN Z. K., 10 Jul. 2025.
Description.
Body (Fig. 2 C View Figure 2 ): Small, slender and sub-cylindrical, males up to 3.4 mm cl, females up to 3.4 mm cl. Sixth abdominal somite 0.41–0.48 times as long as carapace.
Rostrum (Fig. 7 A View Figure 7 ): Short, reaching to the end of the first segment to the middle of the second segment of antennular peduncle, sloping ventral anteriorly; 0.3–0.5 of cl; armed dorsally with 12–15 teeth, including 3–5 on carapace posterior to orbital margin, ventrally with 2–4 teeth; rostral formula 3–5 + 9 – 10 / 2 – 4; lateral carina dividing rostrum into two unequal parts, continuing posteriorly to orbital margin.
Eyes (Fig. 7 A View Figure 7 ): Well-developed, on short ocular peduncle, cornea globular.
Carapace (Fig. 7 A View Figure 7 ): Smooth, glabrous; antennal spine acute, fused with inferior orbital angle; pterygostomian margin broadly rectangular, slightly produced forward; pterygostomian spine absent.
Antennule (Fig. 7 B View Figure 7 ): Peduncle reaching slightly short of scaphocerite; stylocerite reaching 0.86–0.96 times as long as basal segment of antennular peduncle; basal segment shorter or as long as combined length of second and third segments, 1.72–1.96 times as long as second segment; second segment 1.00–1.10 times as long as third segments; all segments with marginal plumose setae.
Antenna (Fig. 7 C View Figure 7 ): Scaphocerite 3.0–3.2 times as long as wide, outer margin straight, asetose, ending in a strong sub-apical spine, inner and anterior margins with long plumose setae.
First maxilliped (Fig. 7 G View Figure 7 ): Palp of first maxilliped broadly triangular, ending in a finger-like projection.
Third maxilliped (Fig. 8 B View Figure 8 ): Basal segment 0.91–1.10 times as long as penultimate segment; penultimate segment as long as distal segment, ending in a large claw-like spine surrounded by simple setae, preceded by 3–5 thin spines on distal third of posterior margin, proximally a clump of long and short simple, serrate setae; exopod reaching beyond the middle of second segment, distal margin with long plumose setae.
First pereiopod (Fig. 8 C View Figure 8 ): Chela 1.90–2.26 times as long as high, 1.21–1.55 times as long as carpus; movable finger 2.55–3.45 times as long as wide and 0.86–1.10 times as long as palm, setal brushes well developed; carpus 1.49–1.94 times as long as wide, slightly excavated distally; merus 0.95–1.16 times as long as carpus.
Second pereiopod (Fig. 8 D View Figure 8 ): Chela 2.30–2.70 times as long as high, 0.75–0.80 times as long as carpus; movable finger 3.50–3.81 times as long as wide and 1.24–1.53 times as long as palm, setal brushes well-developed; carpus 4.59–5.41 times as long as wide, slightly excavated distally; merus 0.74–1.00 times as long as carpus.
Third pereiopod (Fig. 8 E View Figure 8 ): Dactylus 3.36–3.90 times as long as wide, terminating in a prominent claw-like spine surrounded by simple setae, followed by 5 spiniform setae; propodus 3.27–3.83 times as long as dactylus, 8.65–9.43 times as long as wide; carpus 0.60–0.69 times as long as propodus; merus 1.80–2.29 times as long as carpus, with 3–4 spiniform setae on the posterior margin.
Fourth pereiopod: Proportion and spination similar to third pereiopod.
Fifth pereiopod (Fig. 8 F View Figure 8 ): Dactylus 3.13–4.24 times as long as wide, ending in prominent claw-like spine surrounded by simple setae, followed by a row of 29–31 spiniform setae; propodus 3.30–4.24 times as long as dactylus, 9.16–11.29 times as long as wide; carpus 0.54–0.58 times as long as propodus; merus 1.42–1.61 times as long as carpus, with 3 spiniform setae on the posterior margin.
First four pereiopods with epipod.
First pleopod (Fig. 8 G View Figure 8 ): Endopod in male 0.49–0.51 times as long as exopod, oblong-reniform, 2.72–3.34 times as long as distally wide, tip rounded, inner margin concave, bearing nearly equal short spine setae, outer margin slightly convex, long pappose setae on outer and distal margins, medium-length setae on inner margin; appendix interna well developed, arising from distal 0.33 of endopod, reaching slightly beyond end of endopod, distally with cincinuli.
Second pleopod (Fig. 8 H View Figure 8 ): Appendix masculina rod-shaped, reaching 0.69–0.71 length of exopod, some short spiniform setae on basal part, and inner margin and tip bearing nearly equal long and stout spiniform setae; appendix interna well-developed, reaching 0.55–0.57 length of appendix masculina, distally with cincinuli.
Telson (Fig. 8 I View Figure 8 ): Tapering posterior, with a projection, with 4 pairs of short spiniform setae dorsally and one pair of short spiniform setae dorsolaterally; posterior margin with 4 pairs of intermedial spiniform setae, close in length. Exopodite of the uropod (Fig. 8 J View Figure 8 ) bears a series of 14–18 movable spinules along diaresis.
Eggs: 0.58–0.60 mm × 0.92–0.98 mm in diameter. Females of this small-bodied species attain sexual maturity and carry eggs at approximately tl 11 mm.
Remarks.
Caridina wenchangensis sp. nov., is quite similar to C. clinata in rostrum shape and indentation, the proportions between the joints of pereiopods. However, it can be separated from C. clinata by the shorter appendix interna and the different shape appendix masculina of male second pleopod (appendix interna reaching 0.55–0.57 length of appendix masculina, appendix masculina is slightly wider in the middle and slightly narrower at the ends vs. appendix interna reaching 0.52–0.63 of appendix masculina, and appendix masculina is rod-shaped with uniform width in C. clinata ); the fewer spiniform setae on flexor margin of dactylus of fifth pereopod (29–31 spiniform setae vs. 41–51 spiniform setae in C. clinata ); the relatively broader scaphocerite (3.0–3.2 times as long as wide vs. 3.1–3.4 times in C. clinata ); and slightly smaller eggs (0.58–0.60 × 0.92–0.98 mm vs. 0.60–0.75 × 1.10–1.15 mm in C. clinata ).
Caridina wenchangensis sp. nov. indeed resembles C. haivanensis from its sexual appendages, shape of the telson, and the proportions between the joints of the first, third, and fifth pereiopods. However, it can be separated from C. haivanensis by the more dorsal rostral teeth (12–15 teeth vs. 0–3 teeth in C. haivanensis ); the relatively broader chela of second pereiopod (2.30–2.70 times as long as wide vs. 3.07 times in C. haivanensis ); fewer spiniform setae on the flexor margin of the dactylus of the fifth pereiopod (29–31 spiniform setae vs. 30–42 spiniform setae in C. haivanensis ); fewer spinules on the uropodal diaresis (14–18 spinules vs. 22–24 spinules in C. haivanensis ); and the smaller eggs (0.58–0.60 × 0.92–0.98 mm vs. 0.75–0.80 × 1.10–1.30 mm).
Molecular results.
The intraspecific p-distances of COI of the new species were 0 %. The new species is most similar in genetic divergence (p-distance) to C. tunchengensis sp. nov. (9.1 % – 9.4 %) and C. clinata (9.3 % – 9.6 %). According to molecular analysis, the distance between the new species and C. haivanensis is 10.6 %. The intraspecific p-distances of 16 SrRNA of the new species were 0 % – 0.7 %. The new species is most similar in genetic divergence (p-distance) to C. clinata (3.7 % – 4.6 %) and C. huangi sp. nov. (4.1 % – 4.8 %). According to molecular analysis, the distance between the new species and C. haivanensis is 5.5 % – 6.3 % (Fig. 21 View Figure 21 , Suppl. materials 1, 2).
Coloration.
When alive, the female always black and brown with a texture like marble on body, some present a topline on the back. Some transverse black stripes and spots which are irregularly broken at five abdominal of male. (Fig. 2 C View Figure 2 ).
Etymology.
The new species is named after its type locality name: Wenchang City.
Ecological notes.
C. wenchangensis sp. nov. was collected from site 5. At site 5, the stream measured 0.5–1.0 m in width and 0.2–0.3 m in depth, and its substrate consisted of gravel, mud, and leaf litter. The shrimps lived among leaf litter, exhibiting low population density. The stream water was slowly flowing (Fig. 2 C View Figure 2 , Table 1 View Table 1 ).
Distribution.
Only occurring in Chongxing Town, Wenchang City, Hainan Island.
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Fudan University, Department of Biology |
No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.
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