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Neorhynchoplax chipolini sp. nov. A, B, F, paratype female (NMNS7878-2); C-E, holotype male (NMNS7878-1);
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A new hymenosomatid crab, Neorhynchoplax chipolini sp. nov., is described from Taiwan. Of the 32 known species of Neorhynchoplax, only five other species possess a posterolateral tooth on the carapace and unarmed ambulatory dactyli as in N. chipolini sp. nov.: i.e. N. attenuipes. Neorhynchoplax chipolini sp. nov., however , differs from these conge...
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... chipolini sp. nov. Description. Carapace subcircular (range of L/W ratio: 0.94-1.09), surrounded by a distinct rim, not disrupted at base of rostrum; dorsal surface smooth and concave, distinct cervical, thoracic and gastrocardiac grooves present; cervical grooves reaching anterolateral margins, thoracic grooves reaching posterolateral border, with four deep pits at junction of hepatic, prebranchial and gastric areas and junction of postbranchial and cardiac areas near posterolateral border (Fig. 1A). Rostrum distinctly tridentate, lateral teeth triangular with blunt tip, directed anteriorly; median tooth styliform, distinctly bent downwards ( . Third maxilliped longitudinally slender, not fully covering buccal field when closed; ischium shorter than subovate merus; exopod straight, tip reaching to distal margin of merus, flagellum long, anteromesial margin with one tubercle (Fig. 2C, D). Chelipeds elongate, subequal (in male) to equal (in female); merus long, unarmed; carpus subovate; propodus slightly (in female) to moderately (in male) inflated, lower surfaces smooth with irregular mesh-like pattern, margins with rows of setae; dactylus longer than palm, outer and inner surfaces with scattered pubescence, denser along margins, cutting edges of fingers with 4 large teeth, several minute teeth distally and one small tooth proximally, narrow gap present at base of fingers when fully closed (Fig. 2E, F). Ambulatory legs slender (Fig. 1A); inner and outer surfaces with several scattered long setae; distodorsal margin of ischium with one small tubercle (Fig. 3A); dorsal and ventral margins of ischium, merus, carpus and propodus lined with numerous very short curved setae, with many scattered longer setae; distodorsal margin of merus and carpus with a small tuft of short setae; dactylus laterally flatten, falcate, unarmed, sharply tapering distally, lateral surfaces (except for distal part) with few scattered long setae, dorsal and ventral margins with one row of medium setae and several scattered long setae, distal part gently curved, surfaces and margins without setae (Fig. 3B). Pleon subtriangular in male, ovate in mature female, surface with scattered setae, denser along margins; male pleonal somite 1 slightly longer and narrower than somite 2, somites 3-5 fused, fused somites constituting about 60% of pleon+pleotelson length, pleotelson trapezoidal (Fig. 3C). G1 with stout base, slightly bent, upcurved, tapering gradually into narrow distal end; an S-shaped groove present on inner surface of G1; middle portion of G1 with 2 slender setae, subdistal portion of G1 with 3 stout setae processes, median one strongest, longest (Fig. 3D, E). Female pleon oval (range of L/W ratio: 0.79-1.30), somite 1 slightly broader than somite 2 and about same length; somites 3-5 fused, with lateral sutures barely visible, constituting about 80% of pleon+pleotelson length, pleotelson slightly curved toward pleon, broad triangular, lateral margins slightly concave (Fig. 3F); eggs lined against inner surface of pleon and individually kept in sockets (Fig. ...
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... chipolini sp. nov. Description. Carapace subcircular (range of L/W ratio: 0.94-1.09), surrounded by a distinct rim, not disrupted at base of rostrum; dorsal surface smooth and concave, distinct cervical, thoracic and gastrocardiac grooves present; cervical grooves reaching anterolateral margins, thoracic grooves reaching posterolateral border, with four deep pits at junction of hepatic, prebranchial and gastric areas and junction of postbranchial and cardiac areas near posterolateral border (Fig. 1A). Rostrum distinctly tridentate, lateral teeth triangular with blunt tip, directed anteriorly; median tooth styliform, distinctly bent downwards ( . Third maxilliped longitudinally slender, not fully covering buccal field when closed; ischium shorter than subovate merus; exopod straight, tip reaching to distal margin of merus, flagellum long, anteromesial margin with one tubercle (Fig. 2C, D). Chelipeds elongate, subequal (in male) to equal (in female); merus long, unarmed; carpus subovate; propodus slightly (in female) to moderately (in male) inflated, lower surfaces smooth with irregular mesh-like pattern, margins with rows of setae; dactylus longer than palm, outer and inner surfaces with scattered pubescence, denser along margins, cutting edges of fingers with 4 large teeth, several minute teeth distally and one small tooth proximally, narrow gap present at base of fingers when fully closed (Fig. 2E, F). Ambulatory legs slender (Fig. 1A); inner and outer surfaces with several scattered long setae; distodorsal margin of ischium with one small tubercle (Fig. 3A); dorsal and ventral margins of ischium, merus, carpus and propodus lined with numerous very short curved setae, with many scattered longer setae; distodorsal margin of merus and carpus with a small tuft of short setae; dactylus laterally flatten, falcate, unarmed, sharply tapering distally, lateral surfaces (except for distal part) with few scattered long setae, dorsal and ventral margins with one row of medium setae and several scattered long setae, distal part gently curved, surfaces and margins without setae (Fig. 3B). Pleon subtriangular in male, ovate in mature female, surface with scattered setae, denser along margins; male pleonal somite 1 slightly longer and narrower than somite 2, somites 3-5 fused, fused somites constituting about 60% of pleon+pleotelson length, pleotelson trapezoidal (Fig. 3C). G1 with stout base, slightly bent, upcurved, tapering gradually into narrow distal end; an S-shaped groove present on inner surface of G1; middle portion of G1 with 2 slender setae, subdistal portion of G1 with 3 stout setae processes, median one strongest, longest (Fig. 3D, E). Female pleon oval (range of L/W ratio: 0.79-1.30), somite 1 slightly broader than somite 2 and about same length; somites 3-5 fused, with lateral sutures barely visible, constituting about 80% of pleon+pleotelson length, pleotelson slightly curved toward pleon, broad triangular, lateral margins slightly concave (Fig. 3F); eggs lined against inner surface of pleon and individually kept in sockets (Fig. ...
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... chipolini sp. nov. Description. Carapace subcircular (range of L/W ratio: 0.94-1.09), surrounded by a distinct rim, not disrupted at base of rostrum; dorsal surface smooth and concave, distinct cervical, thoracic and gastrocardiac grooves present; cervical grooves reaching anterolateral margins, thoracic grooves reaching posterolateral border, with four deep pits at junction of hepatic, prebranchial and gastric areas and junction of postbranchial and cardiac areas near posterolateral border (Fig. 1A). Rostrum distinctly tridentate, lateral teeth triangular with blunt tip, directed anteriorly; median tooth styliform, distinctly bent downwards ( . Third maxilliped longitudinally slender, not fully covering buccal field when closed; ischium shorter than subovate merus; exopod straight, tip reaching to distal margin of merus, flagellum long, anteromesial margin with one tubercle (Fig. 2C, D). Chelipeds elongate, subequal (in male) to equal (in female); merus long, unarmed; carpus subovate; propodus slightly (in female) to moderately (in male) inflated, lower surfaces smooth with irregular mesh-like pattern, margins with rows of setae; dactylus longer than palm, outer and inner surfaces with scattered pubescence, denser along margins, cutting edges of fingers with 4 large teeth, several minute teeth distally and one small tooth proximally, narrow gap present at base of fingers when fully closed (Fig. 2E, F). Ambulatory legs slender (Fig. 1A); inner and outer surfaces with several scattered long setae; distodorsal margin of ischium with one small tubercle (Fig. 3A); dorsal and ventral margins of ischium, merus, carpus and propodus lined with numerous very short curved setae, with many scattered longer setae; distodorsal margin of merus and carpus with a small tuft of short setae; dactylus laterally flatten, falcate, unarmed, sharply tapering distally, lateral surfaces (except for distal part) with few scattered long setae, dorsal and ventral margins with one row of medium setae and several scattered long setae, distal part gently curved, surfaces and margins without setae (Fig. 3B). Pleon subtriangular in male, ovate in mature female, surface with scattered setae, denser along margins; male pleonal somite 1 slightly longer and narrower than somite 2, somites 3-5 fused, fused somites constituting about 60% of pleon+pleotelson length, pleotelson trapezoidal (Fig. 3C). G1 with stout base, slightly bent, upcurved, tapering gradually into narrow distal end; an S-shaped groove present on inner surface of G1; middle portion of G1 with 2 slender setae, subdistal portion of G1 with 3 stout setae processes, median one strongest, longest (Fig. 3D, E). Female pleon oval (range of L/W ratio: 0.79-1.30), somite 1 slightly broader than somite 2 and about same length; somites 3-5 fused, with lateral sutures barely visible, constituting about 80% of pleon+pleotelson length, pleotelson slightly curved toward pleon, broad triangular, lateral margins slightly concave (Fig. 3F); eggs lined against inner surface of pleon and individually kept in sockets (Fig. ...
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... chipolini sp. nov. Description. Carapace subcircular (range of L/W ratio: 0.94-1.09), surrounded by a distinct rim, not disrupted at base of rostrum; dorsal surface smooth and concave, distinct cervical, thoracic and gastrocardiac grooves present; cervical grooves reaching anterolateral margins, thoracic grooves reaching posterolateral border, with four deep pits at junction of hepatic, prebranchial and gastric areas and junction of postbranchial and cardiac areas near posterolateral border (Fig. 1A). Rostrum distinctly tridentate, lateral teeth triangular with blunt tip, directed anteriorly; median tooth styliform, distinctly bent downwards ( . Third maxilliped longitudinally slender, not fully covering buccal field when closed; ischium shorter than subovate merus; exopod straight, tip reaching to distal margin of merus, flagellum long, anteromesial margin with one tubercle (Fig. 2C, D). Chelipeds elongate, subequal (in male) to equal (in female); merus long, unarmed; carpus subovate; propodus slightly (in female) to moderately (in male) inflated, lower surfaces smooth with irregular mesh-like pattern, margins with rows of setae; dactylus longer than palm, outer and inner surfaces with scattered pubescence, denser along margins, cutting edges of fingers with 4 large teeth, several minute teeth distally and one small tooth proximally, narrow gap present at base of fingers when fully closed (Fig. 2E, F). Ambulatory legs slender (Fig. 1A); inner and outer surfaces with several scattered long setae; distodorsal margin of ischium with one small tubercle (Fig. 3A); dorsal and ventral margins of ischium, merus, carpus and propodus lined with numerous very short curved setae, with many scattered longer setae; distodorsal margin of merus and carpus with a small tuft of short setae; dactylus laterally flatten, falcate, unarmed, sharply tapering distally, lateral surfaces (except for distal part) with few scattered long setae, dorsal and ventral margins with one row of medium setae and several scattered long setae, distal part gently curved, surfaces and margins without setae (Fig. 3B). Pleon subtriangular in male, ovate in mature female, surface with scattered setae, denser along margins; male pleonal somite 1 slightly longer and narrower than somite 2, somites 3-5 fused, fused somites constituting about 60% of pleon+pleotelson length, pleotelson trapezoidal (Fig. 3C). G1 with stout base, slightly bent, upcurved, tapering gradually into narrow distal end; an S-shaped groove present on inner surface of G1; middle portion of G1 with 2 slender setae, subdistal portion of G1 with 3 stout setae processes, median one strongest, longest (Fig. 3D, E). Female pleon oval (range of L/W ratio: 0.79-1.30), somite 1 slightly broader than somite 2 and about same length; somites 3-5 fused, with lateral sutures barely visible, constituting about 80% of pleon+pleotelson length, pleotelson slightly curved toward pleon, broad triangular, lateral margins slightly concave (Fig. 3F); eggs lined against inner surface of pleon and individually kept in sockets (Fig. ...
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... chipolini sp. nov. Description. Carapace subcircular (range of L/W ratio: 0.94-1.09), surrounded by a distinct rim, not disrupted at base of rostrum; dorsal surface smooth and concave, distinct cervical, thoracic and gastrocardiac grooves present; cervical grooves reaching anterolateral margins, thoracic grooves reaching posterolateral border, with four deep pits at junction of hepatic, prebranchial and gastric areas and junction of postbranchial and cardiac areas near posterolateral border (Fig. 1A). Rostrum distinctly tridentate, lateral teeth triangular with blunt tip, directed anteriorly; median tooth styliform, distinctly bent downwards ( . Third maxilliped longitudinally slender, not fully covering buccal field when closed; ischium shorter than subovate merus; exopod straight, tip reaching to distal margin of merus, flagellum long, anteromesial margin with one tubercle (Fig. 2C, D). Chelipeds elongate, subequal (in male) to equal (in female); merus long, unarmed; carpus subovate; propodus slightly (in female) to moderately (in male) inflated, lower surfaces smooth with irregular mesh-like pattern, margins with rows of setae; dactylus longer than palm, outer and inner surfaces with scattered pubescence, denser along margins, cutting edges of fingers with 4 large teeth, several minute teeth distally and one small tooth proximally, narrow gap present at base of fingers when fully closed (Fig. 2E, F). Ambulatory legs slender (Fig. 1A); inner and outer surfaces with several scattered long setae; distodorsal margin of ischium with one small tubercle (Fig. 3A); dorsal and ventral margins of ischium, merus, carpus and propodus lined with numerous very short curved setae, with many scattered longer setae; distodorsal margin of merus and carpus with a small tuft of short setae; dactylus laterally flatten, falcate, unarmed, sharply tapering distally, lateral surfaces (except for distal part) with few scattered long setae, dorsal and ventral margins with one row of medium setae and several scattered long setae, distal part gently curved, surfaces and margins without setae (Fig. 3B). Pleon subtriangular in male, ovate in mature female, surface with scattered setae, denser along margins; male pleonal somite 1 slightly longer and narrower than somite 2, somites 3-5 fused, fused somites constituting about 60% of pleon+pleotelson length, pleotelson trapezoidal (Fig. 3C). G1 with stout base, slightly bent, upcurved, tapering gradually into narrow distal end; an S-shaped groove present on inner surface of G1; middle portion of G1 with 2 slender setae, subdistal portion of G1 with 3 stout setae processes, median one strongest, longest (Fig. 3D, E). Female pleon oval (range of L/W ratio: 0.79-1.30), somite 1 slightly broader than somite 2 and about same length; somites 3-5 fused, with lateral sutures barely visible, constituting about 80% of pleon+pleotelson length, pleotelson slightly curved toward pleon, broad triangular, lateral margins slightly concave (Fig. 3F); eggs lined against inner surface of pleon and individually kept in sockets (Fig. ...
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... chipolini sp. nov. Description. Carapace subcircular (range of L/W ratio: 0.94-1.09), surrounded by a distinct rim, not disrupted at base of rostrum; dorsal surface smooth and concave, distinct cervical, thoracic and gastrocardiac grooves present; cervical grooves reaching anterolateral margins, thoracic grooves reaching posterolateral border, with four deep pits at junction of hepatic, prebranchial and gastric areas and junction of postbranchial and cardiac areas near posterolateral border (Fig. 1A). Rostrum distinctly tridentate, lateral teeth triangular with blunt tip, directed anteriorly; median tooth styliform, distinctly bent downwards ( . Third maxilliped longitudinally slender, not fully covering buccal field when closed; ischium shorter than subovate merus; exopod straight, tip reaching to distal margin of merus, flagellum long, anteromesial margin with one tubercle (Fig. 2C, D). Chelipeds elongate, subequal (in male) to equal (in female); merus long, unarmed; carpus subovate; propodus slightly (in female) to moderately (in male) inflated, lower surfaces smooth with irregular mesh-like pattern, margins with rows of setae; dactylus longer than palm, outer and inner surfaces with scattered pubescence, denser along margins, cutting edges of fingers with 4 large teeth, several minute teeth distally and one small tooth proximally, narrow gap present at base of fingers when fully closed (Fig. 2E, F). Ambulatory legs slender (Fig. 1A); inner and outer surfaces with several scattered long setae; distodorsal margin of ischium with one small tubercle (Fig. 3A); dorsal and ventral margins of ischium, merus, carpus and propodus lined with numerous very short curved setae, with many scattered longer setae; distodorsal margin of merus and carpus with a small tuft of short setae; dactylus laterally flatten, falcate, unarmed, sharply tapering distally, lateral surfaces (except for distal part) with few scattered long setae, dorsal and ventral margins with one row of medium setae and several scattered long setae, distal part gently curved, surfaces and margins without setae (Fig. 3B). Pleon subtriangular in male, ovate in mature female, surface with scattered setae, denser along margins; male pleonal somite 1 slightly longer and narrower than somite 2, somites 3-5 fused, fused somites constituting about 60% of pleon+pleotelson length, pleotelson trapezoidal (Fig. 3C). G1 with stout base, slightly bent, upcurved, tapering gradually into narrow distal end; an S-shaped groove present on inner surface of G1; middle portion of G1 with 2 slender setae, subdistal portion of G1 with 3 stout setae processes, median one strongest, longest (Fig. 3D, E). Female pleon oval (range of L/W ratio: 0.79-1.30), somite 1 slightly broader than somite 2 and about same length; somites 3-5 fused, with lateral sutures barely visible, constituting about 80% of pleon+pleotelson length, pleotelson slightly curved toward pleon, broad triangular, lateral margins slightly concave (Fig. 3F); eggs lined against inner surface of pleon and individually kept in sockets (Fig. ...
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... Of the 10 species of Neorhynchoplax having unarmed ambulatory dactyli, five have a tooth on the posterolateral margins of the carapace as in N. chipolini sp. nov. These are N. attenuipes, N. falcifera, N. sinensis, N. tuberculata, and N. venusta (Kemp 1917: 258, fig. 6; Chopra & Das 1930: 423, text- fig. 10; Shen 1932: 59, text- fig. 33; Dai & Yang 1991: 117, fig. 60; Takeda & Miyake 1971: 158, fig. 1a; Pretzmann 1975: 607, pl fig. 3I; Lucas & Davie 1982: 404, fig. 1; Naruse et al. 2008: 439, fig. 7a; Ng 2015: 195, figs 1A, ...
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... Of the 10 species of Neorhynchoplax having unarmed ambulatory dactyli, five have a tooth on the posterolateral margins of the carapace as in N. chipolini sp. nov. These are N. attenuipes, N. falcifera, N. sinensis, N. tuberculata, and N. venusta (Kemp 1917: 258, fig. 6; Chopra & Das 1930: 423, text- fig. 10; Shen 1932: 59, text- fig. 33; Dai & Yang 1991: 117, fig. 60; Takeda & Miyake 1971: 158, fig. 1a; Pretzmann 1975: 607, pl fig. 3I; Lucas & Davie 1982: 404, fig. 1; Naruse et al. 2008: 439, fig. 7a; Ng 2015: 195, figs 1A, ...
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... biology. Lucas (1980) noted that several species of Neorhynchoplax (as Elamenopsis) have eggs smaller than 0.3 mm diameter. The eggs of Neorhynchoplax chipolini sp. nov. are larger (0.43?0.02 mm, n=6, paratype NMNS7878-5), although it carries as many eggs (carapace width 4.3 mm, 76 eggs) in one brood as N. aspinifera (carapace width 3.0 mm, 77 eggs) (Lucas 1980: 216). It is worth mentioning that eggs of N. chipolini sp. nov., which are lined against the inner surface of abdomen, are individually kept in sockets (Fig. 3G). This protective structure was also observed in N. mangalis (Ng, 1988) and N. yaeyamaensis (cf. Ng & Chuang 1996: 60 fig 1E). noticed females of N. sinensis carry large eggs and suggested they may also be ovoviviparous as are females of N. mangalis ( Ng et al. 1999: ...
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... sinensis from mainland China has a horizontally protruded median rostral tooth and the cervical grooves are completely connected on the anterior carapace (Shen 1932: 59, text- fig. 33), whereas N. chipolini sp. nov., has the median rostral tooth bent downwards and cervical grooves not connected on the anterior carapace (Fig. 1A, B). Unlike N. chipolini sp. nov., N. sinensis has no tubercle on the inner anterolateral margin of the first exopod article of the third maxillipeds (Naruse, pers. comm.; Fig. 2C, D). Moreover, N. chipolini sp. nov. has 2 setae in the middle part of the G1 (Fig. 3D, E), but that of N. sinensis is bare (Shen 1932: 61, text-fig. ...
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... sinensis from mainland China has a horizontally protruded median rostral tooth and the cervical grooves are completely connected on the anterior carapace (Shen 1932: 59, text- fig. 33), whereas N. chipolini sp. nov., has the median rostral tooth bent downwards and cervical grooves not connected on the anterior carapace (Fig. 1A, B). Unlike N. chipolini sp. nov., N. sinensis has no tubercle on the inner anterolateral margin of the first exopod article of the third maxillipeds (Naruse, pers. comm.; Fig. 2C, D). Moreover, N. chipolini sp. nov. has 2 setae in the middle part of the G1 (Fig. 3D, E), but that of N. sinensis is bare (Shen 1932: 61, text-fig. ...
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