Arcania undecimspinosa De Haan 1841
- Dataset
- Description of two new species of Arcania Leach, 1817, from the western Pacific Ocean and redescriptions of A. undecimspinosa De Haan, 1841, and A. elongata Yokoya, 1933 (Crustacea: Brachyura: Leucosiidae)
- Rank
- SPECIES
Classification
- kingdom
- Animalia
- phylum
- Arthropoda
- class
- Malacostraca
- order
- Decapoda
- family
- Leucosiidae
- genus
- Arcania
- species
- Arcania undecimspinosa
description
Redescription. Carapace rounded, dorsal surface covered somewhat sparsely by columnar granules, granules larger at gastric to intestinal regions (Figs. 1 a, 2, 3 a); pterygostomial, subepatic regions evenly covered with rounded granules (Fig. 2 b). Front divided into 2 triangular lobes by obtuse triangular gap, lobes not strongly produced, weakly rounded in some large individuals (Figs. 1 a, 2 a). Carapace with subhepatic, anterolateral, lateral, posterolateral, posterior, intestinal spines. Anterolateral spines smallest, followed in size by subhepatic spine, other spines of almost same length. Only branchiocardiac groove distinct. Antennular fossae oblique, antenna excluded from antenular fossa by plate extended from posterior margin of antennullar basal segment, plate with triangular lobe anteriorly, seta posteriorly. Mesial end of infraorbital margin forming dorsoventrally compressed, sharp, triangular spine. Anteromesial corner of pterygostomial region, anterolateral margin of buccal cavern forming laterally compressed triangular spines fitting distal part of exopod of closed mxp 3; distance between spines relatively narrow due to slender exopod of mxp 3. Eyes fitting within orbit, only corneal part slightly exposed. Mxp 3 (Figs. 2 b, 3 b) sparsely covered with rounded granules; merus length about two-fifths of ischium; ischium, merus each with longitudinal groove on mesial third, half; female merus with longitudinal row of setae along longitudinal groove. Exopod narrowed at level of proximal two-fifths of merus, gap between narrowed part of exopod, merus thus fitting triangular spine of anterolateral margin of buccal cavern. Thoracic sternites 4 – 7 (Fig. 1 b) covered with rounded granules; granulation sparser than pterygostomial region. Sternal button of abdominal holding on anterior end of thoracic sternite 5 at lateral slope of thoracic cavity, button fitting proximolateral cup of somite 6. Penis coxal. Vulva on mesial end of thoracic suture 5 / 6, on somite 6 but extending mesial end of suture 5 / 6 anteriorly (Fig. 6); posterolateral part of vulva swollen; opening narrowed laterally, entire mesially. Chelipeds (Fig. 2 a) moderately long, subequal. Merus slender, shorter than chela, entirely covered with rounded granules, granules smaller on lower surface. Carpus, palm sparsely covered with minute granules, carpus smooth without knob on external margin. Fingers slender, gape absent when closed, with 14 – 18 almost equidistantly placed, small teeth with much smaller teeth throughout. Ambulatory legs slender; merus longest of articles, covered with minute rounded granules. Carpus, propodus covered with minute granules. Dactylus mesiolateraly depressed in cross-section, with sharp keels on mid-lines of mesial, lateral surfaces, keel on lateral surface flanked by rows of setae. Abdomen (Fig. 1 b) with sparse, rounded granules; somites 3 – 5 fused, with proximolateral protuberances on external surface, each protuberance not distinctly larger than central part between two protuberances. Lateral margins of somite 6 convex in large individuals. G 1 (Figs. 4 a – c, 5) slender, nearly straight, slightly curved dorsally in mesial view; distal part only slightly upcurved in mesial view, lateral margin wrapping onto mesial margin submedially, forming pipe-like opening. G 2 (Fig. 4 d) short, opening facing dorsally in situ. Coloration. Body and cheliped merus pinkish dorsally, with a pair of reddish lines and semicircular marks on the dorsal surface (Takeda et al. 2011: fig. 9 – 26). Geographical distribution. Japan (Pacific coast: from Sagami Bay to Kochi; Kyushu: Ariake, Nagasaki [type locality]); Korea (Namcheon-dong, Jinhae-gu); China (Qingdao; Tsimei; Fukien; Hangzhou; Kwangtung; Cheung Chau Island, Hong Kong); Taiwan (Donggang). (De Haan 1844; Shen 1931; Sakai 1937; Miyake 1983; Huang 1989; present study).
discussion
Remarks. Arcania undecimspinosa De Haan, 1841, was described from material collected at Nagasaki, western Kyushu, Japan. Yamaguchi & Baba (1993) and Fransen et al. (1997) listed 15 syntypes, of which five specimens are preserved in ethanol and the rest are dried. The ethanol-preserved specimens comprise three males (two of which are confirmed by the presence of fragmented male thoracic sternites), one female, and one individual (sex unknown). Yamaguchi & Baba (1993) indicated that the ethanol-preserved lot contained a lectotype and paralectotypes, but they did not note nor indicate which individual was selected as lectotype. Since Yamaguchi & Baba’s (1993) lectotype designation is invalid, the lectotype is here designated for a male (RMNH. CRUS. D. 790; 16.5 × 16.5 mm) form the ethanol-preserved specimens (Figs. 1, 4). The lectotype is in a relatively good condition, allowing the observation of the G 1 (Fig. 4 a – c). Arcania undecimspinosa is characterized by a rounded carapace (Figs. 1 a, 2, 3 a), front with triangular lobes with an almost regular triangular gap between the lobes (Figs. 1 a, 2 a, 3 a), distinct marginal spines in the carapace (Figs. 1 a, 2 a, 3 a), dorsal surface of the carapace being rather sparsely covered by columnar granules (granules larger from gastric to intestinal regions) (Fig. 2 b), almost straight G 1 with pipe-like distal end (Figs. 4 a – c, 5) and a vulva consisting of a narrowed lateral end and with an entire mesial margin (Fig. 6).
materials_examined
Material examined. Lectotype: RMNH. CRUS. D. 790, 1 male, 16.5 × 16.5 mm, Nagasaki, Kyushu, Japan, coll. H. Bürger, 1825 – 1834. Paralectotypes: RMNH. CRUS. D. 56126, 1 female, 19.2 × 19.2 mm, 3 individuals (sex unknown), 20.3 × 19.9, 21.1 × 21.1 mm, data same as lectotype. Additional material. Japan: USNM 26280, 1 male, 21.1 × 21.1 mm, 1 female, 21.2 × 21.2 mm, 1 ovig. female, 19.9 × 20.3 mm, Nagasaki, Hizen, Kyushu, coll. Jordan & Snyder, 1900. — USNM 45833, 1 ovig. female, 19.7 × 20.2 mm, Nagasaki, Kyushu, exchange with Imperial Tokyo University. — NSMT-Cr 8371, 1 female, 16.7 × 16.2 mm, Ariake Sea, Kyushu, coll. Sep. 1958. — NSMT-Cr 8200, 1 male, 19.9 × 19.1 mm, Ariake, Kyushu, coll. N. Yoshikawa, 15 June 1982. — NSMT-Cr 8009, 1 male, 16.5 × 15.6 mm, off Jogajima, coll. E. Tsuchida, 11 Mar. 1982. — USNM 1199103, 1 male, Shizuoka, Suruga Bay, Seno Umi, Albatross, stn. D. 3702, 7 May 1900. — USNM 63676, 1 ovig. female, 26.3 × 25.9 mm, Misaki, Japan, coll. A. S. Pearse (bought from Kuma-san), 1930. — NSMT- Cr 3839, 1 female, 24.5 × 23.3 mm, Mikawa-Isshiki, Mikawa Bay, coll. 15 Jan. 1966. — USNM 134198, 19.6 × 18.5 mm, 8.8 mi off Nomasaki, Honshu Island, stn. Alb. D- 3725, 13 faths. (ca. 23.8 m), 15 May 1900. — RUMF- ZC- 2574, 1 female, 12.6 × 9.9 mm, Takehara City, Hiroshima, 15 m, coll. D. Uyeno, 14 Oct. 2007. — NSMT-Cr 4397, 2 males, ca 25.9 × 25.1 mm, 1 female, 28.2 × 27.2 mm, Mimase, Kochi, coll. Y. Koyama, 11 May 1973. — USNM 18873, 1 female, 13.2 × 13.1 mm, Japan, coll. Mr. Sakamoto (passed through Garrett Droppers). Korea: MADBK 171803 - 017, 1 male, 30.3 × 28.7 mm, 1 female, 22.0 × 21.9 mm, Jinhae-gu, Changwon-si, Gyeongsangnam-do, 1 Aug. 1968. — MADBK 171803 - 016, 1 male, 30.1 × 30.8 mm, 2 ovig. female, 29.8 × 30.2, 30.8 × 30.2 mm, Namcheon-dong, Suyeong-gu, Busan, 10 July 1968. China: ZRC 2002.0495, 4 males, 27.2 × 26.7 — 31.0 × 29.8 mm, 1 ovig. female, 31.6 × 31.8 mm, Tuandao, off Qindao, coll. P. K. L. Ng via fishermen, 23 – 28 Aug. 2002. — USNM 57771, 2 males, 23.9 × 24.8, 31.7 × 31.1 mm, 1 female, 32.1 × 35.1 mm, 1 juv. female (damaged), Tsimei (= Jimei, Fujian), coll. S. F. Light, June 1923. Taiwan: ZRC 1997.0382, 1 male, 18.3 × 16.7 mm, Donggang, Pingtung, coll. P. K. L. Ng, 5 Aug. 1996.
Name
- Homonyms
- Arcania undecimspinosa De Haan 1841