Automate anacanthopusoides, Wang, Yan-Rong & Sha, Zhong-Li, 2017

Wang, Yan-Rong & Sha, Zhong-Li, 2017, Description of two new species of the genus Automate De Man, 1888 (Crustacea: Decapoda: Caridea) from the South China Sea, Zootaxa 4238 (1) : -

Automate anacanthopusoides sp. nov.

( Figs. 1–2 )

Automate anacanthopus .— Ledoyer 1970: 127, 149, pl. 17, 24A.

Material examined. Holotype, MBM 270274, 1 ovigerous female (CL 4.9mm, TL 13.7mm), Beibu Gulf, depth 42m, Baolin Zhang Coll., 11 November 1960. Paratype, MBM 210082, 1 ovigerous female (CL 4.2mm, TL 13.5mm), Beibu Gulf, depth 29.9m, Xiutong Ma Coll., 4 December 1959. MBM 210101, 1 ovigerous female (CL 4.1mm, TL 13.4mm), Beibu Gulf, depth 55m, Fuzeng Sun Coll., 13 January 1962. MBM 270166, 1 male (CL 2.2mm, TL 7.8mm), Beibu Gulf, depth 51m, Baolin Zhang Coll., 4 November 1960. MBM 270170, 1 male (CL 4.2mm, TL 13.5mm), Beibu Gulf, depth 21m, Khuêch Coll., 19 October 1962. MBM 210095, 1 male (CL 2.6mm, TL 7.7mm); 1 ovigerous female (CL 4.2mm, TL 11.5mm), Beibu Gulf, depth 30.7m, Zhengang Fan Coll., 19 April 1960. MBM 210076, 1 ovigerous female (CL 3.8mm, TL 10.9mm), Beibu Gulf, depth 22m, Fuzeng Sun Coll., 16 February 1960. MBM 210067, 1 ovigerous female (CL 3.8mm, TL 11.1mm), Beibu Gulf, depth 58m, Fuzeng Sun Coll.. MBM 210099, 2 males (CL 3.6–4.1mm, TL 11.1–12.9mm), Beibu Gulf, depth 58m, Khuêch Coll., 12 October 1962. MBM 210076, 1 ovigerous female (CL 4.8mm, TL 13.5mm), Beibu Gulf, depth 26m, Fuzeng Sun Coll., 8 February 1960. MBM 210071, 1 ovigerous female (CL 4.1mm, TL 12.9mm), Beibu Gulf, depth 65.5m, Zhengang Fan Coll., 21 April 1960. MBM 210061, 1 ovigerous female (CL 4.2mm, TL 13.1mm), Beibu Gulf, depth 57m, Baolin Zhang Coll., 13 July 1960. MBM 210085, 1 ovigerous female (CL 4.1mm, TL 12.8mm), Beibu Gulf, depth 57m, Khuêch Coll., 18 August 1962. MBM 270243, 1 ovigerous female (CL 3.9mm, TL 12.3mm), Beibu Gulf, depth 24.5m, Xiutong Ma Coll., 3 December 1959. MBM 210078, 1 ovigerous female (CL 2.9mm, TL 8.7mm), Beibu Gulf, depth 65.5m, Zhengang Fan Coll., 21 April 1960. MBM 210066, 1 ovigerous female (CL 2.7mm, TL 8.5mm), Beibu Gulf, depth 49m, Zhengang Fan Coll., 19 April 1960. MBM 270169, 1 ovigerous female (CL 4.1mm, TL 12.7mm), Beibu Gulf, depth 28m, Hôńg Coll., 14 February 1960. MBM 210059, 1 male (CL 2.7mm, TL 8.5mm), Beibu Gulf, depth 52m, Zhengang Fan Coll., 14 February 1960. MBM 210059, 1 ovigerous female (CL 2.2mm, TL 7.5mm), Beibu Gulf, depth 40.5m, Fuzeng Sun Coll., 19 April 1960. MBM 270275, 1 male (CL 4.1mm, TL 12.5mm), Beibu Gulf, depth 35m, Shoupeng Shen Coll., 19 October 1960.

Description. Carapace glabrous. Frontal region of carapace ( Figs. 1 A, B, 2O, K) with moderately shallow orbital concavity on either side of rostrum. Rostrum triangular, tip far not reaching to level of antero-lateral margin of carapace, not covering eye-stalks; rostral carina and orbital hoods absent. Eye-stalls ( Figs. 1 A, B, 2O, K) exposed dorsally and laterally; cornea developed. Pterygostomian angle ( Fig. 1 A) rounded, continuous with branchiostegal; cardiac notch conspicuous.

Antennular peduncle ( Figs. 1 B, 2O, K) slender; visible part of first segment about 3 times as long as wide, dorso-mesial margin with one small, somewhat anteriorly curved spine, ventro-mesial carina not terminating anteriorly in acute tooth; second segment much longer than visible part of first segment; stylocerite acute, far not reaching distal end of first segment of antennular peduncle. Antenna ( Fig. 1 A) with basicerite bearing strong ventro-lateral tooth; carpocerite slender, distinctly overreaching distal end of antennular peduncle; scaphocerite ( Figs. 1 B, 2K, O) oval, reaching to about middle of second segment of antennular peduncle, lateral margin slightly concave, disto-lateral tooth distinctly beyond anterior margin of blade.

Mandible ( Fig. 2 E) with two-segmented palp; incisor process bearing distally 4 blunt, strong, large teeth; molar process well developed. Maxillule ( Fig. 2 F) with two endites, distal endite with numerous large spine-like setae on mesial margin, basal endite with one spine-like setae on distal margins; palp bilobed, upper lobe rounded, without seta, lower lobe with two robust seta. Maxilla ( Fig. 2 G) with slender tapering palp; distal endite bilobed, densely setose medially; proximal endite with single lobe, lanceolate, distally with setae; scaphognathite well developed. First maxilliped ( Fig. 2 H) with two-segmented palp; distal endite with medial margin slightly concave, with dense setae; proximal endite small; exopod with well-developed flagellum, distally with long setae; palp twosegmented. Second maxilliped ( Fig. 2 I) with dactylar segment narrow, medial margin with moderately short spiniform setae; propodal segment slightly elongate, rounded distally, distomedial border with long setae; carpus short; coxa with large epipod; exopod with long flagellum, distally with long setae. Third maxilliped ( Fig. 2 J) slender; arthrobranch normally developed; coxa with hook-like epipod, exopod short, tip hardly reaching to midlength of antepenultimate segment; antepenultimate near as long as ultimate segment, superior margin with several moderately short setae; penultimate segment about half length of antepenultimate segment; ultimate segment about 9 times as long as greatest depth, with numerous transverse rows of stiff setae on ventral surface, spine unarmed on distal and dorsal surface.

First pereiopod ( Figs. 1 A, C–G, 2L, P, Q) robust and strongly asymmetrical in shape and size. Major cheliped with ischium bearing one curving row of small spines on mesial face, and one robust spine on dorsal distal margin; merus about twice as long as wide at middle, bearing transverse rows of short setae on ventro-mesial margin; carpus vase-shaped, dorsal surface with one moderately deep transverse groove near distal margin, and ventrodistal surface with one robust spine; palm rectangular, inner margin of about half length bearing densely long setae; fingers distinctly shorter than palm, bearing 1–2 large teeth on cutting edge, inner margin half-length of pollex on mesial face tuberculate and lower margin slightly rugose. Minor cheliped ( Figs. 1 E–G, 2L) with ischium, merus and carpus similar to that of major cheliped; merus about twice as long as wide at middle; carpus about half-length of chela; fingers crossing, cutting edge of dactylus bearing two inconspicuous teeth near tip.

Second pereiopod ( Figs. 1 A, 2A) extremely slender; carpus five-segmented, second segment longer than other segments, ratio of segments from proximal to distal approximately equal to 1.0: 3.0: 1.4: 1.1: 1.4. Third pereiopod ( Fig. 2 B) moderately stout, ischium bearing one spine on ventral margin; merus about five times as long as wide, unarmed; carpus longer than half-length of merus, disto-ventral margin without spines; propodus about 3/5 length of merus, ventral margin bearing long robust setae, without spine; dactylus conical, longer than half-length of propodus, slightly curved, bearing several short setae near tip. Fourth pereiopod ( Fig. 2 C) similar to third pereiopod, but moderately slender. Fifth pereiopod ( Fig. 2 M) similar to third and fourth pereiopod, propodus bearing rows of transverse setae on ventral margin.

Pleon ( Fig. 1 A) with first to fifth pleura rounded postero-ventrally. Telson ( Fig. 2 D) much shorter than uropods, 1.3 times as long as wide at base, dorso-lateral margin bearing two pair of moderately small spines, anterior and posterior pair situated about 1/2 and 3/4 length of telson, respectively; posterior margin slightly convex, bearing two pairs of distal spines, with mesial about seven times as long as lateral.

Second pleopod ( Fig. 2 N) without appendix masculine both sexes. Uropod ( Fig. 2 D) with endopod slightly longer than exopod; exopod with postero-lateral corner sub-acute tooth, slightly produced, accompanied with one spine; diaeresis sinuous, without distinct projection and tooth.

Etymology. “ anacanthopusoides ” meaning the present new species is morphologically similar to the congeneric species A. anacanthopus De Man, 1910 .

Distribution. Present only known from Beibu Gulf, the South China Sea; probable also from Tulear, Madagascar.

Remarks. Anker & Komai (2004) divided the genus Automate into three informal species groups: A. dolichognatha species group, A. evermanni species group and A. hayashii species group. Automate anacanthopusoides sp. nov. is assigned to the A. evermanni species group for having the following features: the rostrum very short; the ventromesial carina on the first segment of the antennular peduncle unarmed; the stylocerite not reaching the distal margin of the basal segment of the antennular peduncle; the scaphocerite narrow; the second maxilliped with podobranch; the palm of the major chela sub-rectangular; the propodus of the third pereiopod without spine; the dactylus of the third pereiopod sub-spatulate; the uropodal endopod slightly exceeding the exopod, and the diaeresis on the uropodal exopod devoid of teeth. The A. evermanni species group contains another five species exclude the new species: A. evermanni Rathbun, 1901 , A. rectifrons Chace, 1972 , A. rugosa Coutière, 1902 , A. branchialis Holthuis & Gottlieb, 1958 and A. anacanthopus De Man, 1910 . The combination of the following features differentiates A. anacanthopusoides sp. nov. from above five species: the rostrum small but present; the lateral margin of the antennal scale sinuous; the distolateral tooth of antennal scale slender, and far overreaching the distal margin of blade; the ventral margin of the major chela bearing deep notch.

The new species is most similar to A. anacanthopus . The original description of A. anacanthopus was not accompanied with illustrations, but subsequently De Man (1911) published somewhat diagrammatic figures of this species. Nevertheless, the major cheliped of the holotype of A. anacanthopus was lost. Bruce (1990) provided the illustration of the major chela based on specimen collected from Hong Kong. According to the original description and illustrations by De Man (1911) and Bruce (1990), A. anacanthopusoides sp. nov. differs from A. anacanthopus by the scaphocerite more reduced, not reaching end of the second segment of antennular peduncle ( De Man 1911, Plate I, Fig. 3 ); the merus of the minor cheliped near twice as long as wide, not reaching 3 times as long as wide ( De Man 1911, Plate I, Fig. 3 B); the carpus of the minor cheliped longer than half length of the merus, rather than only 2/5 length of the merus; the minor chela about twice as long as carpus, rather than more than 3 times longer than it ( De Man 1911, Plate I, Fig. 3 C), and the illustration does not show the spines on the inner side of the ischium of the minor cheliped, the transverse rows of setae on the inner side of the merus of the minor cheliped as well; the cutting edge of the dactylus of the minor chela only bearing two inconspicuous teeth near the tip rather than with small teeth along its whole length, and the cutting edge of the pollex not dentate at base and the tip ( De Man 1911, Plate I, Fig. 3 C; Bruce 1990, Fig. 9B); the lower margin of the major chela with one rather deep notch rather than only slightly concave ( Bruce 1990, Fig. 9A), that illustration also does not show the rugose lower margin of the pollex and the conspicuous processes on the inner side of the pollex. As the characters of the chelipeds always were taken as important features to distinguish species of the Alpheidae , the present specimens were taken as a new species in the paper.

Ledoyer (1970) provided several illustrations of the A. anacanthopus based on specimens from Tulear ( Madagascar), which were similar to the present new species in the deep notch on the lower margin of the major chela; the ratio of the carpus and the chela of the minor cheliped, and in the shape of the merus of the minor cheliped. Thus, the specimens described by Ledoyer (1970) could be the present new species.

Figures

FIGURE 1. Automate anacanthopusoides sp. nov., holotype, female (MBM 270274), CL 4.9 mm. A, body in lateral view; B, anterior margin of carapace, dorsal view; C, left major cheliped; inner view; D, same, outer view; E, right minor cheliped, inner view; F, same, chela, outer view; G, same, fingers, outer view. Scale bars: a = 2 mm; b, e – g = 0.5 mm; c, d = 1 mm.

FIGURE 2. Automate anacanthopusoides sp. nov., holotype, female (MBM 270274), CL 4.9 mm. A, left second pereiopod; B, right third pereiopod; C, right fourth pereiopod; D, left uropod and telson; E, left mandible; F, left maxillule; G, left maxilla; H, left first maxilliped; I, left second maxilliped; J, maxilliped. paratype, female (MBM 210082), CL 4.2 mm. K, anterior margin of carapace, dorsal view; L, minor cheliped, outer view; M, fifth pereiopod; N, second pleopod. paratype, female (MBM 210101), CL 4.1 mm. O, anterior margin of carapace, dorsal view; P, major cheliped, inner view; Q, same, fingers, outer view. Scale bars: a – o, q = 0.5 mm; p = 1 mm.

FIGURE 3. Automate dolichognatha De Man, 1888, female (MBM 270027), CL 4.1 mm. A, anterior margin of carapace, dorsal view; B, same, lateral view; C, D, major cheliped; E, right second pereiopod; F, right third pereiopod; G, same, propodus and dactylus; H, right fourth pereiopod; I, same, propodus and dactylus; J, right fifth pereiopod; K, same, propodus and dactylus; L, right second pleopod; M, telson and right uropod; N, left mandible; O, left maxillule; P, left maxilla; Q, left first maxilliped; R, left second maxilliped; S, left third maxilliped. Scale bars: a, b, f – r = 0.5 mm; c – e = 1 mm.