identifier	taxonID	type	CVterm	format	language	title	description	additionalInformationURL	UsageTerms	rights	Owner	contributor	creator	bibliographicCitation
767087EFC855484CB559F8A3213DFAC2.text	767087EFC855484CB559F8A3213DFAC2.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Caridina tricincta Do & Rintelen & Dang 2020	<div><p>Caridina tricincta, new species</p><p>(Figs. 2–4)</p><p>Material examined. Holotype male, cl 5.3 mm (IEBR–FS 001), Vietnam: Tuyen Quang Province, Na Hang District, <a href="https://tb.plazi.org/GgServer/search?materialsCitation.longitude=105.38586&amp;materialsCitation.latitude=22.445026" title="Search Plazi for locations around (long 105.38586/lat 22.445026)">Khau Tinh Commune</a>, 22°26′42.1″N 105°23′09.1″E, coll. Nguyen Anh Tuan, 11 December 2014 . Paratypes: 22 females, cl 3.6–6.8 mm, 19 males, cl 4.0– 5.5 mm (ZMB 29641), same data as holotype; 2 males, cl 4.0 mm, 4.2 mm (ZMB 30360), Vietnam: Ha Giang Province, Bac Me District, <a href="https://tb.plazi.org/GgServer/search?materialsCitation.longitude=105.26039&amp;materialsCitation.latitude=22.73851" title="Search Plazi for locations around (long 105.26039/lat 22.73851)">Lac Nong Commune</a>, 22°44′18.635″N 105°15′37.397″E, coll. Do Van Tu &amp; Dang Van Dong, 16 October 2019 ; 2 females, cl 3.7 mm, 4.3 mm (ZMB 30363), Vietnam: Ha Giang Province, Bac Me District, <a href="https://tb.plazi.org/GgServer/search?materialsCitation.longitude=105.23611&amp;materialsCitation.latitude=22.740248" title="Search Plazi for locations around (long 105.23611/lat 22.740248)">Lac Nong Commune</a>, 22°44′24.894″N 105°14′9.989″E, coll. Do Van Tu &amp; Dang Van Dong, 16 October 2019 .</p><p>Comparative material. Caridina clinata Cai, Quynh &amp; Ng, 1999: male, cl 3.1 mm (ZMB 30664), Vietnam: Ninh Binh Province, small stream in <a href="https://tb.plazi.org/GgServer/search?materialsCitation.longitude=105.62838&amp;materialsCitation.latitude=20.319756" title="Search Plazi for locations around (long 105.62838/lat 20.319756)">Cuc Phuong National Park</a>, 20°19′11.118″N 105°37′42.168″E, coll. Thomas von Rintelen &amp; Do Van Tu, 03 April 2017.</p><p>Description. Carapace length 3.6–6.8 mm (median 5.0 mm). Rostrum straight or slightly curved downwards, short, reaching to middle or slightly falling short of distal end of basal segment of antennular peduncle, 0.14–0.31 (median 0.25) times as long as carapace, rostral formula: 0–6+0–3/0–5 (n = 33), teeth small (Fig. 2A). Suborbital angle acute, completely fused with antennal spine; pterygostomian margin rounded (Fig. 2A). Eyes well developed with globular cornea, anterior end reaching to 0.7 times length of basal segment of antennular peduncle (Fig. 2A). Antennular peduncle 0.42–0.6 (median 0.49) times as long as carapace; basal segment 1.29–2.0 (median 1.71) times as long as second segment, second segment 1.14–1.5 (median 1.29) times as long as third segment (Fig. 2B). Stylocerite reaching distal end of basal segment of antennular peduncle (Fig. 2B). Scaphocerite ovate, reaching beyond distal end of antennular peduncle, 2.45–3.43 (median 2.86) times as long as wide (Fig. 2A, C).</p><p>Sixth abdominal somite 0.35–0.42 (median 0.4) times length of carapace, 1.47–1.91 (median 1.75) times as long as fifth abdominal somite, 0.76–0.9 (median 0.84) times length of telson. Telson length 1.91–2.75 (median 2.25) times as long as proximal wide, distal margin triangular, terminating in a very short median projection, with 4–5 pairs of dorsal spinules and one pair of dorso-subdistal spinules; distal end with 4–5 pairs of spines, lateral pair slightly longer than intermediate pairs (Fig. 2D, E). Preanal carina low, with few setae, lacking tooth or spine (Fig. 2F). Uropodal diaeresis with 12–18 movable spinules, outermost one slightly longer than lateral angle (Fig. 2G).</p><p>Incisor process of mandible ending in one row of 5–6 irregular teeth, molar process truncated (Fig. 2H). Lower lacinia of maxillula broadly rounded, upper lacinia elongated, with number of distinct teeth and setae on inner margin, palp stout with few simple setae at tip (Fig. 2I). Upper endites of maxilla subdivided, palp short, scaphognathite tapering posteriorly, with numerous long, curved setae at posterior margin (Fig. 2J). Distal end of palp of first maxilliped triangular, with a short projection; flagellum of the exopod very elongated, endopod high, reaching 0.75 times length of flagellum of exopod (Fig. 2K, L). Podobranch of second maxilliped incompletely reduced, with few finger-like projections (Fig. 2M). Third maxilliped reaching to distal end of antennular peduncle, ending in single terminal claw, exopod reaching 0.4 times length of penultimate segment; ultimate segment slightly shorter than penultimate segment (Fig. 2N). Branchial formula as is typical for genus, five pairs of pleurobranchs well developed; three pairs of arthrobranchs, two on third maxillipeds, with second pair strongly reduced in size, one pair on first pereopod; one pair of podobranchs on second maxilliped strongly reduced.</p><p>Epipod present on first three pereopods. First pereopod short, robust, reaching beyond end of basal segment of antennular peduncle; chela 1.69–2.14 (median 2.0) times as long as wide, 1.43–1.88 (median 1.53) times length of carpus; tips of fingers rounded, without hook; dactylus 1.08–1.67 (median 1.24) times as long as palm; carpus excavated anteriorly, 1.13–1.58 (median 1.4) times as long as wide, 0.68–0.94 (median 0.83) times length of merus; merus 2.0–2.57 (median 2.54) times as long as wide, longer than ischium (Fig. 3A). Second pereopod long, slender, reaching to distal end of antennular peduncle; chela 2.61–3.0 (median 2.82) times as long as wide, 0.76–0.96 (median 0.89) times length of carpus; tips of fingers rounded, without hook; dactylus 1.42–1.91 (median 1.54) times as long as palm; carpus 4.38–5.17 (median 4.71) times as long as wide, 1.0–1.13 (median 1.03) times as long as merus; merus 4.2–5.17 (median 4.85) times as long as wide, longer than ischium (Fig. 3B). Third pereopod slender, reaching beyond end of scaphocerite by its dactylus, terminating in two claws, with four or five accessory spines on flexor margin, dactylus 2.67–3.33 (median 2.88) times as long as wide (terminal claw and spines on flexor margin included), propodus 10.23–11.25 (median 10.86) times as long as wide, 3.8–4.8 (median 4.24) times as long as dactylus; carpus 4.15–5.18 (median 5.0) times as long as wide, 0.44–0.67 (median 0.61) times as long as propodus, 0.46–0.58 (median 0.5) times as long as merus; merus 6.12–8.68 (median 7.5) times as long as wide, bearing three strong, movable spines on posterior margin of outer surface; ischium with a small spinule (Fig. 3C, D). Fifth pereopod slender, reaching to end of second segment of antennular peduncle, dactylus 3.0–4.0 (median 3.25) times as long as wide (terminal claw and spines on flexor margin included), terminating in one large claw, with 33–46 spinules on flexor margin; propodus 12.0–13.0 (median 12.58) times as long as wide, 3.23–4.17 (median 3.43) times length of dactylus; carpus 4.33–5.25 (median 4.81) times as long as wide, 0.46–0.55 (median 0.5) times as long as propodus, 0.59–0.71 (median 0.64) times as long as merus; merus 6.0–7.32 (median 6.2) times as long as wide, bearing 3–4 strong, movable spines on posterior margin of outer surface (Fig. 3E, F).</p><p>Endopod of male first pleopod extending to 0.7 times exopod, rectangular in shape, 3.0–3.25 (median 3.0) times as long as proximal width, inner margin concave, outer margin slightly convex, rounded distally, long plumose setae on outer and distal margins, medium-length setae on inner margin; with appendix interna exceeding terminal margin of endopod by 0.3–0.5 its length (Fig. 3G, H). Appendix masculina of male second pleopod stout, reaching to proximal 0.5 times endopod length, 6.0 times as long as distal width, fingershaped, with some short spinules on outer surface and some long spinules on distal surface; appendix interna at the middle of appendix masculina, extending about 0.9 times length of appendix masculina (Fig. 3I, J).</p><p>Habitat. This species was found in a stream with mixed sand, gravel, and rock substratum, and clear flowing water from the forest (Fig. 4A).</p><p>Colouration. The body is dark grey. Three black transverse stripes are present on the carapace, third and sixth abdominal somites, respectively, interleaved with three narrower grey transverse stripes (Fig. 4).</p><p>Etymology. The name ‘ tricincta ’ (L. tri – three; cinctus – belt or girdle) refers to the three characteristic transverse stripes on the body of live specimens of this species. Used as an adjective.</p><p>Remarks. Caridina tricincta, new species, is quite similar to C. clinata Cai, Quynh &amp; Ng, 1999, from Ninh Binh province, northeast Vietnam, in the shape of the endopod of male first pleopod. However, it can be separated by the number of teeth located on the dorsal surface including the teeth on the carapace posterior to the orbital margin (0–7 teeth vs. 13–21 teeth); proportion of the chela of the second pereopod (2.61–3.0 times as long as wide vs. 2.5 times as long as wide); proportion of the propodus of the third pereopod (10.23–11.25 times as long as wide vs. 9 times as long as wide in C. clinata; and 3.8–4.8 times as long as dactylus vs. 3.6 times as long as dactylus in C. clinata); proportion of the endopod of the male first pleopod (3.0–3.25 times as long as wide vs. 2.8 times as long as wide in C. clinata); and the live colour patterns (distinct and unbroken black transverse stripes are present vs. black patterns are unobvious, thin and irregularly broken in C. clinata) (Figs. 2A, 3B, H, 4A, B; cf. Cai et al., 1999: figs. 1A–C, G–I, 2F).</p><p>Caridina tricincta, new species, is also similar to C. baoting Cai, 2014, from Hainan Island and C. serrata Stimpson, 1860, from Hong Kong, southern China, in the shape of the rostrum and the endopod of male first pleopod. Caridina tricincta, new species, can be distinguished from C. baoting by a suite of characteristics: the fingers of the first pereopod are slightly longer than the palm (vs. as long as palm in C. baoting); the carpus of the first pereopod is 1.13–1.58 times as long as wide (vs. 1.7 times as long as wide in C. baoting); the chela of the second pereopod is 2.61–3.0 times as long as wide (vs. 2.4 times as long as wide in C. baoting); the endopod of male first pleopod is 3.0–3.25 times as long as wide (vs. 2.8 times as long as wide in C. baoting); the appendix interna extends about 0.9 times length of appendix masculina (vs. 0.4 times length of appendix masculina in C. baoting); and the uropodal diaeresis has 12–18 movable spinules (vs. 20–23 movable spinules in C. baoting) (Figs. 2, 3; cf. Cai, 2014: figs. 8, 9).</p><p>When compared to C. serrata Stimpson, 1860, the new species Caridina tricincta can be easily distinguished, by fewer teeth on the dorsal margin of the rostrum (excluding the teeth on the carapace posterior to orbital margin) (viz. 0–3 teeth vs. 5–12 teeth in C. serrata), and a shorter stylocerite, just reaching the distal end of basal segment of the antennular peduncle (vs. extending beyond the end of basal segment of the antennular peduncle in C. serrata) (Fig. 2A, B; cf. Cai &amp; Ng, 1999: figs. 2, 3).</p><p>The rostrum shape and the endopod of male first pleopod of Caridina tricincta, new species, are quite similar to that of C. sumatianica Cai &amp; Yuan, 1996, from Hongyan Village, Chishui region, Guizhou Province, China. However, C. tricincta, new species, can be distinguished from C. sumatianica by the number and position of the ventral teeth of the rostrum (0–5 not close to the tip vs. 2–4 teeth close to tip in C. sumatianica); the stylocerite reaching the end of the basal segment of the antennular peduncle (vs. stylocerite only 0.75 times length of basal segment in C. sumatianica); and the endopod of the male first pleopod being 3.0–3.25 times as long as its proximal width (vs. 2.5 times in C. sumatianica) (Figs. 2A, B, 3H; cf. Cai &amp; Yuan, 1996: figs. 22, 23).</p></div>	https://treatment.plazi.org/id/767087EFC855484CB559F8A3213DFAC2	Public Domain	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.		Plazi	Do, Van Tu;Rintelen, Thomas von;Dang, Van Dong	Do, Van Tu, Rintelen, Thomas von, Dang, Van Dong (2020): Descriptions of two new freshwater shrimps of the genus Caridina H. Milne Edwards, 1837 (Crustacea: Decapoda: Atyidae) from northern Vietnam. Raffles Bulletin of Zoology 68: 404-420, DOI: 10.26107/RBZ-2020-0057
767087EFC8514847B7A0FA84205CF7C2.text	767087EFC8514847B7A0FA84205CF7C2.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Caridina pacbo Do & Rintelen & Dang 2020	<div><p>Caridina pacbo, new species</p><p>(Figs. 5–7)</p><p>Material examined. Holotype male, cl 4.2 mm (IEBR–FS 003), Vietnam: Cao Bang Province, Ha Quang District, Truong Ha Commune, Pac Bo Village, small stream in Khuoi Nam, 22°59′1.7″N 106°02′31.2″N, coll. Do Van Tu, 25 May 2017 . Paratypes: 5 females, cl 5.0– 6.3 mm; 2 males, cl 4.2–4.5 mm (ZMB 30295), same data as holotype .</p><p>Comparative material. Caridina nguyeni Li &amp; Liang, 2002: male, cl 3.2 mm (ZMB 30280), Vietnam: Cao Bang, Ha Quang, Truong Ha, <a href="https://tb.plazi.org/GgServer/search?materialsCitation.longitude=106.04825&amp;materialsCitation.latitude=22.984446" title="Search Plazi for locations around (long 106.04825/lat 22.984446)">Pac Bo</a>, a small creek run into <a href="https://tb.plazi.org/GgServer/search?materialsCitation.longitude=106.04825&amp;materialsCitation.latitude=22.984446" title="Search Plazi for locations around (long 106.04825/lat 22.984446)">Le Nin</a> stream, 22°59′4.0″N 106°02′53.7″E, coll. Do Van Tu, 25 May 2017; male, cl 3.3 mm (ZMB 30283), Vietnam: Cao Bang, Ha Quang, Lung Nam, a small stream runs along the road of <a href="https://tb.plazi.org/GgServer/search?materialsCitation.longitude=106.06863&amp;materialsCitation.latitude=22.976109" title="Search Plazi for locations around (long 106.06863/lat 22.976109)">Thin Tang village</a>, 22°58′33.99″N 106°04′7.06″E, coll. Do Van Tu, 25 May 2017. Caridina cucphuongensis Dang in Dang, Thai &amp; Pham, 1980: male, cl 3.8 mm; 2 females, cl 4.2–4.4 mm (ZMB 30234), Vietnam: Ninh Binh, Cuc Phuong National Park, a small stream near the footpath to the one thousand year old tree (in Vietnamese name: chò), 20°21′0.779″N 105°36′11.675″E, coll. Thomas von Rintelen &amp; Do Van Tu, 03 April 2017.</p><p>Description. Carapace length 4.2–6.3 mm (median 5.2 mm). Rostrum slightly curved downwards, short, reaching beyond middle or close to end of basal segment of antennular peduncle, 0.25–0.36 (median 0.3) times as long as carapace, rostral formula: 5–12+2–6/0–3 (n = 8), teeth small (Fig. 5A). Suborbital angle acute, completely fused with antennal spine; pterygostomian margin rounded (Fig. 5A). Eyes well developed with globular cornea, anterior end reaching to 0.6 times length of basal segment of antennular peduncle (Fig. 5A). Antennular peduncle 0.35–0.62 (median 0.49) times as long as carapace; basal segment 1.38–1.67 (median 1.67) times as long as second segment, second segment 1.2–1.33 (median 1.33) times as long as third segment (Fig. 5B). Stylocerite mostly reaching beyond the end of basal segment, sometimes to the middle of second segment of antennular peduncle (Fig. 5B). Scaphocerite ovate, reaching beyond distal end of antennular peduncle, 2.64–3.13 (median 2.73) times as long as wide (Fig. 5C).</p><p>Sixth abdominal somite 0.37–0.51 (median 0.46) times length of carapace, 1.25–1.77 (median 1.4) times as long as fifth somite, 0.95–1.08 (median 1.0) times length of telson. Telson length 1.77–1.92 (median 1.91) times as long as proximal wide, distal margin round with median projection, with 4–5 pairs of dorsal spinules and one pair of dorso-subdistal spinules; distal end with four pairs of spines, lateral pair slightly longer than intermediate pairs (Fig. 5D, E). Preanal carina high, with few setae, lacking a spine (Fig. 5F). Uropodal diaeresis with 19–20 movable spinules, outermost one as long as lateral angle (Fig. 5G).</p><p>Incisor process of mandible ending in one row of six irregular teeth, molar process truncated (Fig. 5H). Lower lacinia of maxillula broadly rounded, upper lacinia elongated, with a number of distinct teeth and setae on inner margin, palp short and stout with few simple setae at tip (Fig. 5I). Upper endites of maxilla subdivided, palp short, scaphognathite tapering posteriorly, with numerous long, curved setae at posterior margin (Fig. 5J). Distal end of palp of first maxilliped triangular, with a short projection; flagellum of the exopod very elongated, endopod high, reaching 0.67 times length of the flagellum of exopod (Fig. 5K, L). Podobranch of second maxilliped incompletely reduce to a lamina with few fingerlike projections (Fig. 5M). Third maxilliped reaching to end of antennular peduncle, ending in single terminal claw, exopod reaching to 0.3 times length of penultimate segment; ultimate segment as long as penultimate segment (Fig. 5N). Branchial formula as is typical for genus, five pairs of pleurobranchs well developed; three pairs of arthrobranchs, two on third maxillipeds, with second pair strongly reduced in size, one pair on first pereopod; one pair of podobranchs on second maxilliped strongly reduced.</p><p>Epipod present on first four pereopods. First pereopod short, robust, reaching the end of basal segment of antennular peduncle; chela 2.07–2.40 (median 2.2) times as long as wide, 1.45–1.6 (median 1.5) times length of carpus; tips of fingers rounded, without hook; dactylus 0.75–0.95 (median 0.83) times as long as palm; carpus excavated anteriorly, 1.31–1.67 (median 1.5) times as long as wide, 0.75–0.88 (median 0.8) times length of merus; merus 2.75–3.8 (median 2.78) times as long as wide, 1.21–1.29 (median 1.25) times longer than chela, longer than ischium (Fig. 6A). Second pereopod long, slender, reaching to end of antennular peduncle; chela 2.67–3.09 (median 2.82) times as long as wide, 0.77–0.86 (median 0.78) times length of carpus; tips of fingers rounded, without hook; dactylus 1.57–1.78 (median 1.67) times as long as palm; carpus 4.25–5.0 (median 4.89) times as long as wide, as long as merus; merus 5.0–5.86 (median 5.45) times as long as wide, longer than ischium (Fig. 6B). Third pereopod slender, reaching beyond end of scaphocerite by its dactylus, terminating in one claw, with four or five accessory spines on flexor margin, dactylus 2.25–2.5 (median 2.47) times as long as wide (terminal claw and spines on flexor margin included), propodus 8.4–9.33 (median 8.98) times as long as wide, 3.89–4.2 (median 4.19) times as long as dactylus; carpus 4.71–5.54 (median 4.88) times as long as wide, 0.76–0.83 (median 0.78) times as long as propodus, 0.51–0.58 (median 0.54) times as long as merus; merus 5.56–6.36 (median 6.05) times as long as wide, bearing three strong, movable spines on posterior margin of outer surface; ischium with a small spinule (Fig. 6C, D). Fifth pereopod slender, reaching to end of second segment of antennular peduncle, dactylus 2.25–2.5 (median 2.47) times as long as wide (terminal claw and spines on flexor margin included), terminating in one large claw, with 28–45 spinules on flexor margin; propodus 11.78–12.57 (median 12.13) times as long as wide, 4.89–5.3 (median 4.90) times length of dactylus; carpus 4.0–4.6 (median 4.15) times as long as wide, 0.5–0.57 (median 0.54) times as long as propodus, 0.63–0.66 (median 0.64) times as long as merus; merus 5.06–5.47 (median 5.13) times as long as wide, bearing 3–4 strong, movable spines on posterior margin of outer surface (Fig. 6E, F).</p><p>Endopod of male first pleopod extending to 0.8 times exopod, rectangular in shape, anterior region folding backwards, 2.86–3.33 (median 3.09) times as long as proximal width, inner margin concave, outer margin slightly convex, rounded distally, long plumose setae on outer and distal margins, medium-length setae on inner margin; with appendix interna distinctly exceeding terminal margin of endopod (Fig. 6G, H). Appendix masculina of male second pleopod slender, reaching to proximal 0.7 times endopod length, 8.0 times as long as distal width, rod-shaped, with some short spinules on outer surface and some long spinules on distal surface; appendix interna at the middle of appendix masculina, extending about 0.6 times length of appendix masculina (Fig. 6I, J).</p><p>Habitat. This new species was found in a streamlet with mixed sand, gravel, and bedrock substratum, and clear flowing water from the forest (Fig. 7).</p><p>Colouration (from a colour photograph taken immediately after collection). Few irregular small black spots are present on the ventrolateral parts of the carapace. Five transverse black stripes which are irregularly broken at five abdominal somites (Fig. 8).</p><p>Etymology. The new species is named ‘ pacbo ’ after the type locality name: Pac Bo, Ha Quang, Cao Bang Province, northeast Vietnam. The name is used as a noun in apposition.</p><p>Remarks. Phylogenetic analysis of Vietnamese atyid shrimps indicates that Caridina pacbo, new species, is closest to C. pseudoserrata Dang &amp; Do, 2007, both described from Cao Bang Province (see below). Caridina pacbo, new species, can be distinguished from C. pseudoserrata by these characters: the rostrum reaches the middle or close to the end of basal segment of the antennular peduncle (vs. rostrum reaches middle of second segment of the antennular peduncle in C. pseudoserrata); the teeth on the rostrum are small (vs. moderate size in C. pseudoserrata); the chela of the first pereopod is 2.07–2.40 times as long as wide (vs. 1.8 times as long as wide in C. pseudoserrata); the dactylus of the chela is shorter than the palm (vs. equal or slightly longer than palm in C. pseudoserrata); the chela of the second pereopod is 2.67–3.09 times as long as wide (vs. 2.25 as long as wide in C. pseudoserrata); and the appendix interna distinctly exceeds the terminal margin of the endopod of the male first pleopod (vs. reaching to anterior margin of endopod or slightly exceeding it in C. pseudoserrata) (Figs. 5, 6; cf. Dang &amp; Do, 2007a: figs. 1, 2).</p><p>Caridina pacbo, new species, can be included in the C. serrata group because of a long stylocerite extending beyond the distal end of the basal antennular peduncle, the presence of dorsal teeth on the carapace, and the endopod of the male pleopod having a distinctive appendix interna (see Cai &amp; Ng, 1999). However, C. pacbo, new species, differs from C. serrata in: the first pereopod chela being 2.07–2.40 times as long as wide (vs. 2.0 times as long as wide in C. serrata); the first pereopod merus being 1.21–1.29 times longer than the chela (vs. as long as chela in C. serrata); and the endopod of the male first pleopod being 2.86–3.33 times as long as its proximal width (vs. 2.5 times as long as proximal width in C. serrata) (Figs. 5, 6; cf. Cai &amp; Ng, 1999: figs. 2, 3).</p><p>Caridina pacbo, new species, can be easily distinguished from C. nguyeni Li &amp; Liang, 2002, which was also described from Cao Bang province, by its shorter rostrum, reaching to the middle or close to the end of the basal segment of the antennular peduncle (vs. reaching to the end of the third segment of antennular peduncle in C. nguyeni); fewer number of teeth on the rostrum, armed dorsally with 8–17 teeth including 2–6 teeth on the carapace, ventrally with 0–3 teeth (vs. armed dorsally with 20–25 teeth including 9–12 teeth on carapace, ventrally with 4–6 teeth in C. nguyeni); and the dactylus of the fifth pereopod bearing 28–45 spinules on its flexor margin (vs. 25–27 spinules in C. nguyeni) (Figs. 5, 6; cf. Li &amp; Liang, 2002: figs. 1, 2).</p><p>The type locality of C. pacbo, new species, is close to Bama County, Guangxi Province, China, where C. bamaensis Liang &amp; Yan, 1983, was described. Caridina bamaensis is similar to C. pacbo, new species, in the shape of the rostrum and the endopod of male first pleopod. However, the new species can be distinguished from C. bamaensis by: the rostrum sometimes reaching near the end of the basal segment of the antennular peduncle, with teeth on both dorsal and ventral margins (vs. not reaching near the end of basal segment of the antennular peduncle, without teeth on both dorsal and ventral margins in C. bamaensis); the stylocerite mostly reaching beyond the end of basal segment of the antennular peduncle, or sometimes to the middle of second segment of antennular peduncle (vs. only reaching to the end of basal segment of the antennular peduncle in C. bamaensis); the carpus of second pereopod is as long as the merus (vs. longer than merus in C. bamaensis); and the inner margin of the endopod of the male first pleopod is slightly concave (vs. strongly concave in C. bamaensis) (Figs. 5, 6; cf. Liang &amp; Yan, 1983: figs. 1–10).</p><p>Caridina pacbo, new species, also looks similar to another species, Paracaridina zijinica Liang, 2002, described from Zijin County, Guangdong, China, in the shape of the rostrum and the endopod of male first pleopod. However, the new species differs in the branchial formula being complete with nine pairs of branchials (vs. branchial formula is incomplete with eight pairs of branchials, the base of the first pereopod without arthrobranchiae in P. zijinica), the rostrum possessing 2–6 teeth on the carapace behind posterior margin of orbital margin (vs. without teeth in P. zijinica), and the teeth on the rostrum being smaller (vs. moderate size in P. zijinica) (Figs. 5, 6; cf. Liang, 2002: fig. 3).</p><p>The shapes of the rostrum, chela of first pereopod, endopod of male first pleopod, appendix masculina of male second pleopod, and appendix interna of the new species show similarities with Caridina cucphuongensis Dang in Dang, Thai &amp; Pham, 1980. However, compared to C. cucphuongensis, the new species is easily separated by the shorter rostrum, which reaches beyond the middle or close to the distal end of the basal segment of the antennular peduncle (vs. reaching proximal part to sometimes middle of second segment of antennular peduncle in C. cucphuongensis); the smaller rostral teeth (vs. relatively large in C. cucphuongensis); the most posterior tooth of dorsal rostrum-carapace teeth row being close to the second most posterior tooth (vs. far from the second tooth in C. cucphuongensis); the scaphocerite being 2.64–3.13 times as long as wide (vs. 2.50 times as long as wide in C. cucphuongensis); and the endopod of the male first pleopod being 2.86–3.33 times as long as proximal width (vs. 2.5 times as long as proximal width in C. cucphuonensis) (Figs. 5, 6; cf. Dang et al., 1980: fig. 230).</p><p>Molecular taxonomy of Vietnamese atyid shrimps. All sequenced individuals of Caridina tricincta, new species, cluster within all examined Vietnamese (and Chinese) atyids, which form a rather distinct clade with some Chinese species (Fig. 9A, B). Genetic divergence within and among the three sequenced populations (ZMB 29641, ZMB 30360, ZMB 30363) (Fig. 9A, Table 2) of C. tricincta, new species, is rather low with a maximum intraspecific divergence (p-distance) of 1.5% (COI) and 0.4% (16S), respectively (Tables 3, 4). In contrast, it is well isolated from its congeners with a minimum sequence divergence (p-distance) of 15.1% (COI) and 6.7 % (16S), respectively, supporting that C. tricincta, new species, is distinct from all examined species (Tables 3, 4).</p><p>Caridina pacbo, new species, is possibly sister species to C. pseudoserrata (Fig. 9A). It is well isolated from C. pseudoserrata with a sequence divergence (p-distance) of 8.7–8.8% (COI), and from all other Vietnamese species in the dataset by a minimum divergence of 12.2%, supporting that C. pacbo, new species, is distinct from all examined species. Genetic distances (uncorrected, p-distance) for the COI and 16S dataset are provided in Tables 3 and 4, respectively.</p><p>The phylogenetic trees (Fig. 9) do provide little to no resolution of the relationships of Vietnamese atyids. Both new species are represented in the COI tree, while Caridina pacbo, new species, could not be sequenced for 16S. However, this was to be expected given the limited taxonomic coverage of the dataset, and that a phylogeny of Vietnamese atyids has not been the aim of this paper. Rather, we intended to use a second independent suite of characters to seek support for the morphological differences found, in line with an integrative taxonomy approach (Padial et al., 2010). The trees clearly show that the two new species described here are distinct from any of the Vietnamese and Chinese species examined in our phylogeny (and the species that are not represented for lack of samples and thus, sequences are morphologically rather distinct). As outlined in the introduction, no study on Vietnamese atyids thus far has gone beyond using morphological data, which makes it – also considering the lower quality of some older drawings – difficult to reliably identify species. By providing DNA sequences of two gene fragments commonly used for species delimitation purposes, we hope to contribute towards a more sustainable approach to atyid taxonomy in Vietnam and surrounding areas.</p></div>	https://treatment.plazi.org/id/767087EFC8514847B7A0FA84205CF7C2	Public Domain	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.		Plazi	Do, Van Tu;Rintelen, Thomas von;Dang, Van Dong	Do, Van Tu, Rintelen, Thomas von, Dang, Van Dong (2020): Descriptions of two new freshwater shrimps of the genus Caridina H. Milne Edwards, 1837 (Crustacea: Decapoda: Atyidae) from northern Vietnam. Raffles Bulletin of Zoology 68: 404-420, DOI: 10.26107/RBZ-2020-0057
