Pugettia ferox, Ohtsuchi & Kawamura, 2019

Ohtsuchi, Naoya & Kawamura, Tomohiko, 2019, Redescriptions of Pugettia quadridens (De Haan, 1837) and P. intermedia Sakai, 1938 (Crustacea: Brachyura: Epialtidae) with description of a new species, Zootaxa 4672 (1), pp. 1-68 : 34-46

Pugettia ferox n. sp.

[New Japanese name: Oh-yotsuha-mo-gani]

( Figs. 26–38 )

Pugettia quadridens .— Shen 1932: 49, pl. 2, fig. 2, text-figs. 26–30; 1937: 287–289, text fig. 5b, c, e, h.— Vinogradov 1950: 235, pl. 42, fig. 149.— Shen & Dai 1964: 39, unnumbered figure.— Kobyakova 1966: 213, pl. 41, fig. 1.— Levin 1976: 54, fig. 107.— Griffin & Tranter 1986: 97 (in part), fig. 28e, f.— Dai & Yang 1991: 129–130, pl. 14(4), fig. 66(2).— Muraoka 1998: 24 (in part).— Marumura & Kosaka 2003: 32 (in part).— Nunomura 2010: 52–53 (in part).— Lee et al. 2014: 47, figs. 3A, 4A.— Ko & Lee 2015: 19, figs. 1B, 2A, B, pls. 11, 12 [not Pisa (Halimus) quadridens De Haan, 1837 ]

Pugetti [sic.] quadridens .— Sakai 1938: 255–257 (in part), text-fig. 28b. [not Pisa (Halimus) quadridens De Haan, 1837 ]

part).— Kim & Kim 1998: 302–303, figs. 1, 2 [not Pugettia quadridens intermedia Sakai, 1938 ]

Pugettia quadridens quadridens .— Kim 1973: 529 (key), 530–532, pl. 53 fig. 194.— Kim & Kim 1998: 303–304.— Miyake 1983: 35, pl. 12, fig. 2; 1998: 35, pl. 12, fig. 2.— Honma & Muraoka 1992: 41, fig. 2E.— Ariyama 1995: 1, 3, fig. 3. [not Pisa (Halimus) quadridens De Haan, 1837 ]

Pugettia quadridens intermedia .— Ikeda 1981: 15 (in part).— Kim & Kim 1998: 302–303, figs. 1, 2 [not Pugettia quadridens intermedia Sakai, 1938 ]

Pugettia intermedia .— Marumura & Kosaka 2003: 32 (in part). [not Pugettia quadridens intermedia Sakai, 1938 ]

Pugettia pellucens .— Marumura & Kosaka 2003: 32 (in part) [not Pugettia quadridens pellucens Rathbun, 1932 ]

Pugettia incisa .— Nunomura 2010: 52 (in part) [not Pisa (Halimus) incisa De Haan, 1837 ]

? Pugettia quadridens .— Miers 1879: 23 (in part).— Rathbun 1902: 28 (in part).— Doflein 1902: 655.— Balss 1924: 24 (in part).— Yokoya 1933: 148 (in part). [see Discussion]

Material examined. Holotype: male (40.0 × 32.1 mm) (NSMT-Cr 26069), 2–4 m, Akahama, Otsuchi Bay , Iwate, SCUBA +hand, coll. K. Nakamoto, 14 Feb. 2017.

Allotype: female (27.9 × 22.6 mm) (NSMT-Cr 26070), boulder zone, 5 m, off Horai-jima Islet , Otsuchi Bay, SCUBA +hand, coll. K. Fukuda, 27 Feb. 2013.

Paratypes: Three males (27.4 × 23.3–33.7 × 28.2 mm) , 1 female (21.8 × 17.7 mm) (RUMF-ZC-4975), same data as allotype ; 1 male (30.7 × 26.3 mm) (NSMT-Cr 26071), boulder zones, 5 m, Akahama, Otsuchi Bay , Iwate, SCUBA +hand collection, coll. K. Nakamoto, 24 Jan. 2017 ; 3 males (5.5 × 3.8–25.1 × 20.1 mm), 1 female (17.2 × 13.6 mm) (NSMT-Cr 26072), Sargassum yezoense beds, 5 m, same locality and date as previous, SCUBA +hand, coll. N. Ohtsuchi ; 3 males (22.8 × 18.3–39.3 × 33.9 mm) (NSMT-Cr 26073), 1 male (40.3 × 33.5 mm) ( CBM-ZC 14879 ), with Sargassum sp., 2 m, Akkeshi Bay , Hokkaido, baited trap, coll. S. Houki & K. Fukuda, 1 Sep. 2012 ; 1 male (8.8 × 6.2 mm), 1 female (10.1 × 7.2 mm) ( CBM-ZC 14878 ), red algal turfs, 4–5 m, Tomarihama, Oshika Peninsula , Miyagi, coll. N. Ohtsuchi, 24 Aug. 2011 ; 2 males (15.1 × 11.5, 19.8 × 14.7 mm), 3 females (15.4 × 11.6–22.8 × 18.3 mm), 1 ovigerous female (17.5 × 13.9 mm) ( CBM-ZC 14880 ), near low tidal mark, algal turfs of A. paradoxa, Oarai, Kashima Sea , Ibaraki, hand collection, coll. N. Ohtsuchi & S. Houki, 8 May 2012 .

Non-types: Japan. Eight males (12.7 × 8.9–32.0 × 22.3 mm), 6 females (15.1 × 11.0–28.6 × 22.8 mm), 1 ovigerous female (28.2 × 23.0 mm) (NSMT-Cr 11233), Soya Strait, Hokkaido, T. Miyauchi, 13 Jul. 1991 ; 2 males (20.0 × 15.8, 32.7 × 27.6 mm), 1 female (25.7 × 21.5 mm) ( CBM-ZC 10791 ), Kabutoiwa, Shakotan Peninsula , Hokkaido, SCUBA diving, coll. T. Komai, 26 Aug. 2007 ; 1 male (39.4 × 33.4 mm) (NSMT-Cr 26076), Sakae-ura, Saroma Lake , Hokkaido, coll. S. Chiba, 9 May 2016 ; 2 females (28.7 × 23.5, 11.7 × 9.4 mm) (OMNH-Ar 10708), Notoro Lake , Hokkaido, coll. S. Chiba, 7 Oct. 2016 ; 2 males (6.2 × 4.4, 9.5 × 7.1 mm), 1 female (10.4 × 7.8 mm), 1 female (with a rhizocephalan parasite, 15.6 × 11.6 mm) (SMBL-Ar 1452), Abashiri , Hokkaido, coll. T. Yam, 12 Aug. 1960 ; 4 males (17.3 × 13.0–22.0 × 15.9 mm), 1 female (20.8 × 16.3 mm) (NSMT-Cr 3262), same locality as previous, coll. S. Sato, 30 Aug. 2008 ; 1 male (16.5 × 13.3 mm) (OMNH-Ar 10709), Cape Shiretoko , Hokkaido, coll. S. Chiba, 2 Nov. 2013 ; 1 male (24.5 × 18.3 mm) ( CBM-ZC 10819 ), 2–5 m, Bunkichi Bay, Shiretoko Peninsula , Hokkaido, coll. T. Komai, 16 Sep. 2008 ; 2 males (33.3 × 27.7, 36.2 × 29.4 mm) (NSMT-Cr 10261), 2–3 m, Goyoumai, Kushiro , Hokkaido, coll. H. Hayashi, 7 Dec. 1977 ; 3 males (17.9 × 13.9–32.0 × 25.9 mm), 1 female (28.4 × 23.7 mm) (RUMF-ZC-4981), Off Aikappu, Akkeshi Bay , Hokkaido, epibenthic sled, coll. T. Yorisue, S. Hamano, H. Katsuragawa & R. Yoshida, 9 Sep. 2015 ; 3 males (25.9 × 20.3–32.4 × 25.4 mm) (RUMF-ZC-4982), same locality and date as previous, trap, coll. T. Yorisue, S. Hamano, H. Katsuragawa & R.Yoshida ; 2 males (32.1 × 26.4, 36.2 × 29.3 mm) (RUMF-ZC-4983), pier of Akkeshi Marine Station, Akkeshi Bay , Hokkaido, trap, coll. R. Yoshida, 15 Sep. 2015 ; 3 females (9.7 × 6.6–11.0 × 8.3 mm) (SMBL-Ar 1453), Shirikishinai , Hokkaido, coll. T. Yam, 30 Aug. 1960 ; 1 male (24.2 × 22.9 mm) (WMNH-Na-Cr 0312-1), Hokkaido, coll. S. Nagai, Jul. 1981 ; 2 males (13.9 × 9.6, 21.8 × 17.8 mm), 2 females (11.2 × 8.3, 22.9 × 18.1 mm) (NSMT-Cr 17720), Miyako Bay , Iwate, coll. S. Koyama, 29 Aug. 1937 ; 1 female (28.0 × 21.7 mm), 3 ovigerous females (18.3 × 13.4–22.8 × 17.5 mm) (NSMT-Cr 17729), Funakoshi Bay, Shimohei , Iwate, coll. S. Koyama, 2–30 Aug. 1937 ; 1 male (13.2 × 8.9 mm) (NSMT-Cr 8389), 50 m, Otsuchi Bay , Iwate, coll. M. Takeda, 21 Jul. 1982 ; 4 males (8.3 × 5.8–19.1 × 13.8 mm), 1 female (13.7 × 9.5 mm), 1 juvenile (5.6 × 3.5 mm) (NSMT-Cr 8390), 38 m, Otsuchi Bay , Iwate, coll. M. Takeda, 21 Jul. 1982 ; 1 female (13.2 × 9.4 mm) (NSMT-8391), 17.5 m, Otsuchi Bay , coll. M. Takeda, 21 Jul. 1982 ; 1 male (9.2 × 7.0 mm) (OMNH-Ar 10706), Akahama, Otsuchi Bay , understory of Saccharina japonica var. diabolica beds, 2–4 m, SCUBA +air-lifting sampler, coll. M. Kodama, 26 Nov. 2015 ; 1 male (4.4 × 3.1 mm) (OMNH-Ar 10705), same locality as previous, understory of Phyllospadix iwatensis beds, 2–4 m, SCUBA +air-lifting sampler, coll. M. Kodama, 25 Feb. 2016 ; 1 male (5.4 × 3.7 mm) (OMNH-Ar 10707), same locality and habitat as previous, SCUBA +air-lifting sampler, coll. M. Kodama & J. Hayakawa, 16 May 2017 ; 1 male (31.8 × 24.4 mm) (NSMT-Cr 17682), Ohya, Motoyoshi-cho, Motoyoshi-gun , Miyagi, coll. Ibayashi, 10 Mar. 1933 ; 1 female (24.9 × 18.9 mm) (NSMT-Cr 17674), Baba, Karakuwa-machi, Motoyoshi-gun , Miyagi, coll. S. Ohfuchi, 10 Mar. 1933 ; 1 female (9.9 × 7.3 mm) (RUMF-ZC-4978), red algal turfs, 4–5 m, Tomarihama, Oshika Peninsula , Miyagi, SCUBA +air-lifting sampler, coll. T. Kawamura & H. Takami, 29 Jul. 2010 ; 1 female (12.0 × 9.2 mm) (RUMF-ZC-4979), same habitat and locality as previous, SCUBA +air-lifting sampler, coll. T. Kawamura & H. Takami, 10 Nov. 2010 ; 1 male (6.7 × 4.8 mm) (RUMF-ZC- 4980), same habitat and locality as previous, SCUBA +air-lifting sampler, coll. T. Kawamura & H. Takami, 24 Aug. 2011 ; 3 females (8.4 × 6.3–8.7 × 6.4 mm) (RUMF-ZC-4976), 1 female (10.1 × 7.2 mm), 4 ovigerous females (16.7 × 12.7–21.0 × 17.8 mm) (RUMF-ZC-4977), same habitat, locality, and sampling method as previous, coll. N. Ohtsuchi, 24 Aug. 2011; 3 males (22.1 × 17.8–25.5 × 21.5 mm), 1 female (19.9 × 16.0 mm), 1 ovigerous female (19.1 × 15.6 mm) ( CBM-ZC 14881 ), 5 m, boulder zone, Tomarihama, Oshika Peninsula , SCUBA, coll. T. Kawamura & N.-I. Won, 9 Jul. 2011 ; 9 males (15.7 × 12.4–25.2 × 19.6 mm), 1 female (12.9 × 9.7 mm), 1 ovigerous female (20.8 × 15.5 mm) (NSMT-Cr 17637), Nakanosaku, Ena, Iwaki , Fukushima, coll. S. Ohfuchi & H. Kakuda, 3 Aug. 1932 ; 7 males (12.5×9.1–23.6× 19.3 mm) (NSMT-Cr 26075), near low tidal mark, Sargassum sp. beds on rocky reef, Nagasaki, Iwaki , Fukushima, hand collection, coll. N. Ohtsuchi, 2 Feb. 2017 ; 3 males (19.2 × 15.3–23.1 × 19.4 mm), 3 females (21.3 × 17.4–22.4 × 18.0 mm) ( CBM-ZC 14882 ), near low tidal mark, Ahnfeltia paradoxa turf on rocky reef, Misaki, Iwaki , Fukushima, hand collection, coll. N. Ohtsuchi, 2 Feb. 2017 ; 2 females (31.3 × 24.4, 35.0 × 29.3 mm) (NSMT-Cr 19866), Onahama, Iwaki , Fukushima, coll. H. Kakuda, 20 Jun. 1931 ; 1 male (32.8 × 28.8 mm) (WMNH-Na-Cr 0312-1), Choshi, Boso Peninsula , 80 m, coll. T. Watanabe, 1988 ; 2 males (17.0 × 13.5, 20.7 × 17.2 mm) ( CBM-ZC 14884 ), intertidal, Gelidium elegans turfs, Inubosaki Light , hand collection, coll. N. Ohtsuchi & S. Houki, 9 May 2012 ; 1 male (27.3 × 22.3 mm) ( CBM-ZC 2230 ), Tomiyama Fishery Port , Minami-Boso-shi, Chiba, rafts for aquaculture, hand collection, coll. T. Komai, 25 Dec. 1995 ; 4 males (26.5 × 21.6–18.1 × 13.1 mm), 5 ovigerous females (13.1 × 10.3–18.4 × 14.2 mm) (KPMNH- 110366 – 110374), Sagami Bay ; 1 female (34.4 × 29.0 mm) (WMNH-Na-Cr 0314-1), Hayama , coll. S. Nagai, 6 May 1973 ; 1 male (17.2 × 13.6 mm) (NSMT-Cr 26074), near low tidal mark, S. fusiforme beds, rocky beach behind Morito Shrine, Hayama, Sagami Bay , hand collection, coll. N. Ohtsuchi, 29 Apr. 2009 ; 2 males (18.3 × 14.1, 11.2 × 8.4 mm) (OMNH-Ar 6294), Oura, Takeno-cho, Kinosakigun , Hyogo, coll. R. Yamanishi, 25 Jul. 1999 ; 1 male (30.4 × 24.9 mm) (OMNH-Ar 3048), Tanagawa, Misaki-cho , Sennan-gun, Osaka, 28 Jul. 1986 ; 1 male (17.8 × 13.1 mm) (OMNH-Ar 6023), Tanigawa, Misaki-cho, Sennan-gun , Osaka, coll. H. Ariyama, 24 May 1994 (figured in Ariyama 1995) ; 1 male (27.9 × 22.9 mm) ( CBM-ZC 14885 ), ca. 50–80 m, off Kitaura Port, Oga Peninsula, Akita Prefecture, Northern Japan , gill-net, coll. M. Marumura, 23 Nov. 1994 ; 1 male (12.7 × 12.0 mm), 1 female (8.5 × 5.5 mm) (TOYA-Cr 10454), Nozaki, Notojima-cho , Ishikawa, coll. H. Nambu, 25 Jul. 1990 ; 2 males (16.0 × 12.2, 8.0 × 5.7 mm), 2 females (5.9 × 4.3, 8.2 × 5.9 mm) (TOYA-Cr 17320), Miyazaki Fishery Port, Miyazaki, Asahi-cho , Toyama, coll. H. Nambu, 11 Nov. 2008 ; 1 male (18.1 × 14.9 mm) (ZMUC-CRU-20232), Nagasaki, coll. James Jordan, 1 Jul. 1911 (figured in Griffin & Tranter 1986).

North China. One ovigerous female (18.0 × 14.2 mm) ( MBM 160494), Yantai , coll. Yang Jing, 1 Jul. 1957 ; 1 female (20.2 × 15.3 mm) ( MBM 160497), Xishawang , Yantai, 22 Mar. 1975 ; 1 male (23.2 × 18.5 mm) ( MBM 160514 ), exact locality unknown, 12 Feb. 1960 ; 1 male (20.3 × 15.5 mm), 1 female (20.4× 18.8 mm) ( MBM 160515 ), Changxing Island , coll. Fangzeng Sun, 6 Oct. 1956 ; 4 males (10.1 × 7.4–15.8 × 12.1 mm) ( MBM 160513 ), Kong tong Island, Yantai, Shanton, North China , 7 Apr. 1951 .

Description. Male. Full-grown males (18.1–40.5 mm PCL, including holotype and paratypes). Carapace ( Fig. 26A ) pyriform, 1.1–1.3 longer than width (PCL/CW = 1.2±0.0, N = 19), surface smooth to naked eyes but closely covered with microscopic setae; gastric, cardiac, branchial, intestinal regions unclearly separated from each other. Gastric region ( Fig. 26C ) moderately elevated, always anteriorly with oblique row of dense hooked setae on either side of midline ( Figs. 26A, C , 37G ); mesogastric, metagastric, protogastric region on both sides each with subacute protuberance ( Figs. 26A , 37G ). Hepatic, cardiac, branchial regions moderately elevated; cardiac region separated from branchial region on each side by irregularly rugose groove ( Figs. 25C , 37G ); mesobranchial regions elevated, as high as cardiac regions, with 2–3 (2 in general) obtuse tubercles apically, mesial one larger than lateral ones ( Figs. 26A , 37G ); metabranchial regions faintly elevated, with low, obtuse tubercle. Intestinal region ( Fig. 26A, C ) moderately elevated, with obtuse protuberance apically, separated from cardiac region.

Pseudorostral spines ( Figs. 26A , 27A ) short, length 0.1–0.2 of post-pseudorostral carapace length (PRL/PCL = 0.2±0.0, N = 20), each with two rows of dense, hooked setae on proximal two-third dorsally, single row of long setae on proximal 0.8 mesially; lateral margins subparallel. Preorbital spine ( Figs. 26A , 28A, B ) slender, generally compressed dorsoventrally, directed anterolaterally, acuminate at tip, with row of slender setae on mesial margin ( Fig. 28A ). Supraorbital eave ( Figs. 26A , 28A, B ) moderately extended laterally, lateral margin sinuous. Orbital hiatus ( Figs. 26A , 28A ) deep, rounded, triangular concavity. Postorbital lobe ( Figs. 26A , 27A , 28A ) small, triangular, shorter than preorbital spine, weakly compressed dorsoventrally, directed anteriorly or anterolaterally, weakly incurved distally. Hepatic lobe ( Figs. 26 , 27A , 28A ) not demarcated from hepatic region, broad, triangular, immediately narrowed distally, more than twice longer than postorbital lobe (HpL/PoL = 2.4±0.3, N = 15), compressed dorsoventrally, directed anterolaterally, acuminate at tip, variably incurved distally ( Fig. 37 ). Anterolateral carapace margin ( Figs. 26A , 27A ) always with rows of sparse, hooked setae; lateral surface inferior to anterolateral margin with 3–5 (3 in general) spines. Epibranchial spine ( Fig. 26A ) longer than postorbital lobe, shorter than hepatic lobe, directed anterolaterally, weakly incurved, acuminate at tip, positioned at posterior 0.4 of postorostral carapace length (ESL/PCL = 0.4±0.0, N = 18), confluent to posterolateral carapace margin basally. Posterolateral carapace margin ( Fig. 26A ) faintly convex. Posterior carapace margin ( Fig. 26A ) weakly projected roundly.

Subhepatic region ( Fig. 26B ) narrowly exposed in ventral view, with few, sparse, hooked setae. Pterygostomial region ( Fig. 26B ) not particularly inflated, with 4–5 (4 in general) papiliform tubercles along pleural suture. Anterolateral angle of buccal frame ( Fig. 27A ) produced anteriorly, not overlapped by anterolateral angle of merus of third maxilliped when closed, subrectangular in lateral view.

Basal antennal article ( Fig. 28B ) smooth on surface, bearing blunt, faintly granulate longitudinal ridge mesial to midline; mesial margin grooved; distolateral angle moderately produced into spine directed anterolaterally; lateral margin extended laterally, concave, sometimes faintly granulate ( Fig. 28C ), proximal end produced into triangular lobe, separated from posterior orbital margin, with subacute tubercle basally ( Fig. 28B ). Antennal peduncle ( Fig. 28D ) consisting of two articles; penultimate article ( Fig. 28D ) generally subcylindrical, broadened distally, with lateral margin bluntly carinate over entire length, distal end almost twice broader than proximal end; ultimate article ( Fig. 28D ) two-thirds of penultimate article in length, flattened dorsoventrally, slightly broadened distally; penultimate, ultimate articles with few, noticeably long setae on distomesial angle.

Third maxilliped ( Figs. 26B , 28E ) smooth on surface. Ischium with shallow, broad median depression, lateral margin nearly straight. Merus with dilated, faintly upturned anterolateral angle. Exopod almost half of ischium in maximum width, dilated laterally, immediately narrowed in distal two-fifth, mesial margin with blunt angle on distal one-third ( Fig. 28E ).

Chelipeds ( Figs. 26A, B , 29 , 30 ) equal in size, similar in shape. Ischium ( Fig. 26B ) weakly swollen ventrally in distal half; mesial margin obtusely crested, bearing 2–3 (3 in general) teeth, truncate in anterior end; distolateral lobe distinct, compressed, rounded apically. Merus ( Fig. 29 D–G) prismatic, length 2.7 longer than height (2.7±0.1, N = 10); dorsal surface ( Fig. 29 D–F) with broad, longitudinal keel bearing 3–6 distinct (3 in general) teeth, distalmost largest, directed anteriorly; outer surface ( Fig. 29 E–G) faintly rugose, with blunt longitudinal ridge, with 2– 3 (3 in general) rudimentary teeth; ventral surface ( Fig. 29F, G ) with blunt ridge bearing 3–4 (3 in general) low, broad teeth; inner surface ( Fig. 29D, E, G ) depressed, irregularly rugose, with blunt, longitudinal ridge terminated in subtriangular, proximal lobe; distal margin ( Fig. 29 E–G) with 2 prominent knobs at articulation with carpus (outer knob larger than inner), prominent, obliquely erect, subrectangular lobe with moderately long, acute projection on upper side. Carpus ( Fig. 29 A–C) moderately inflated, blunt ridge bearing 2–3 (2 in general) low tubercles on dorsal surface ( Fig. 29A ); outer margin obtusely ridged, irregularly dentate ( Fig. 29A, B ); ventral surface ( Fig. 29C ) uneven; inner margin obtusely crested, irregularly dentate, with acute, proximal lobe ( Fig. 29A ). Chelae ( Fig. 30A ) more than twice longer than height (ChL/ChH = 2.3±0.1, N = 19); palm strongly expanded, upper margin obtusely ridged, lower margin poorly defined; immovable fingers with subpentagonal teeth along distal two-thirds (similar in size); movable finger with low, broad teeth ( Figs. 26A, B , 30A ); both fingers narrowly gaped in proximal half when closed ( Fig. 30A ).

Ambulatory legs ( Figs. 26 , 31 ) decreasing in length posteriorly, surface generally smooth to naked eyes but closely covered with microscopic setae. Meri weakly flattened, each with distinct, upper distal tubercle ( Fig. 31A ), more than six times longer than height in P2 (6.5±0.6, N = 10), more than four times in P3 (4.5±0.4, N = 10). Carpi each with shallow, medial depression on extensor surface ( Fig. 31B ). Propodi weakly flattened, moderately narrowed in flexor half, each with setal tufts on proximal 0.8 on flexor margin in P2, 0.6 in P3–P5 ( Fig. 31A, C ). Dactyli each with two rows of low, calcareous spines on flexor surface ( Fig. 31A, C ).

Thoracic sternites ( Figs. 26B , 32A, B ) smooth on surface, with shallow, broad depression on second to fourth sternite on both side; second sternite with pair of small depression anteriorly (often continuous to shallow depression on second to fourth sternites); third to fourth sternites obtusely ridged medially ( Fig. 32A ); sterno-abdominal cavity weakly ridged, without long setae on anterolateral margins ( Fig. 32B ).

Pleon ( Figs. 26B , 32B ) with six plomeres and telson; third to sixth pleomeres fixed, with distinct suture. Third pleomere broadest, lateral margin oblique; fourth pleomere trapezoid, as long as fifth in midline length; fifth pleomere trapezoid; sixth pleomere rectangular, dilated on distolateral angle, 0.6 of third pleomere in proximal width (0.6±0.0, N = 5); telson triangular.

Shaft of G1 ( Fig. 33A, E ) straight, trilobate in distal one-sixth; dorsal lobe elongate, triangular, with subacute tip, more than twice longer than ventral lobe, curved inwards, elevated basally to form incomplete lobate projection ( Fig. 33 A–D); ventral lobe triangular, with subacute tip, pointing upwards ( Fig. 33 A–D); mesial lobe as long as ventral lobe, projecting anteriorly obliquely, weakly twisted distally ( Fig. 33A, B, D ); hiatus between dorsal, mesial lobes moderately wide ( Fig. 33D ); mesial, lateral margins from dorsal lobe to ventral lobe concave; lateral margin lower than lateral margin of ventral lobe, with median dilation followed by lobule ( Fig. 33 B–D). Shaft of G2 ( Fig. 33H ) stout, narrowed distally, truncated apically; apex with relatively large, acuminate process ( Fig. 33I ).

Adolescent males (11.2–32.4 mm PCL) ( Fig. 35A, B ). Chelae ( Fig. 30B ) proportionally longer (ChL/ChH = 2.8±0.2, N = 30) than in full-grown males ( Table 1 , see also Fig. 35B ), not gaped, both fingers uniformly dentate on cutting margin ( Figs. 30B , 35B ). G1 trilobate apically as in full-grown males.

Immature males (<9.2 mm PCL) ( Fig. 36A, B ). Carapace relatively slender (PCL/CW = 1.4±0.1, N = 5). Chela slenderer (ChL/ChH = 2.9±0.1, N = 3) than in adolescent males ( Table 1 , see also Fig. 36B ), similar to adolescent specimens in dentation on both fingers. G1 incompletely folded, otherwise folded but but provided with rudimentary, mesial lobe projecting anterolaterally ( Fig. 33J, K ).

Female. Full-grown females (12.7–28.7 mm PCL, including allotype and paratypes). Carapace ( Figs. 27B , 34A ) similar to males in general proportion (PCL/CW = 1.3±0.0, N = 16; PRL/PCL = 0.2±0.0, N = 14; ESL/PCL = 0.4±0.0, N = 16) (Student t -test, p> 0.05); mesobranchial region more elevated than in males ( Figs. 27B , 34A, F versus Figs. 26A , 27A ). Cheliped merus slenderer than in males (length/height = 2.9±0.2, N = 10; Student t -test, p <0.01); chelae ( Fig. 30C ) much proportionally longer than in full-grown males (ChL/ChH = 2.8±0.2, N = 30; Student t -test, p <0.01). Tufts of few elongate setae sometimes on midlines of protogastric region, midpoint of epibranchial region, apex of epibranchial spines, summits of cardiac and intestinal regions ( Fig. 38C ). Pleon ( Fig. 34B ) with six pleomeres and telson, expanded (PW6/PW3 = 1.4±0.1, N = 8). Gonopore ( Fig. 32D, E ) comma-shaped, suboval in lateral half, elongate in mesial half.

Adolescent females (9.9–16.9 mm PCL) ( Fig. 35C, D ). Chela slender (ChL/ChH = 2.8±0.0, N = 4), similar to full-grown individuals in dentation. Pleon ovate (PW6/PW3 = 1.3±0.1, N = 7).

Immature females (<11.0 mm PCL) ( Fig. 36C, D ). Carapace relatively slender (PCL/CW = 1.4, N = 8) than in the other ontogenetic stages ( Table 1 , see also Fig. 36C ). Chela slender (ChL/ChH = 2.8±0.1, N = 7). Pleon suboval (PW6/PW3 = 1.1±0.1, N = 9).

Variations. Carapace tends to be broader, from 1.4 to 1.1 in PCL/CW, in relation to size growth ( Figs. 26 , 34–38 ). Tuberculation on gastric, mesobranchial, and metabranchial regions more prominent in larger specimens in the same ontogenetic stage ( Fig. 37A, D, E ); tubercles on mesobranchial region count three, getting more prominent in larger specimens ( Figs. 26 , 37 ). HpL/PoL increases from 1.6 to 3.0 in relation to size growth ( Fig. 39 ). Both fingers of chela sometimes do not contact in distal half ( Fig. 37A ). Ambulatory legs are often provided with sparse, long setae but they tend to be reduced in larger specimens ( Figs. 26 , 35–38 ). Spinulation on ambulatory leg dactyli often reduced in larger specimens probably due to ablasion ( Fig. 31A, C ). Hiatus between dorsal and mesial lobes of G1 variable in width; lobule on subdistal part of lateral margin of G1 variable in size and distinctness (arrowed in Fig. 33D, F ).

Size. Largest male: 40.5 × 34.3 mm; largest female: 35.0 × 29.3 mm; smallest ovigerous female: 16.4 × 12.8 mm.

Coloration in life. The carapace is generally dark red, reddish brown or dark green ( Fig. 38A, C, E, F ); some specimens with some whitish or dark-colored blotches and/or dense speckles ( Fig. 38A, E, F ). The general coloration of the thorax, pleon, chelipeds, and ambulatory legs are white or yellowish brown ( Fig. 38C, D ). The coloration of chelipeds reduced in flexor surface; palms generally dark red to dark green, with scale-like patterning ( Fig. 38A ). Ambulatory legs with whitish band of variable width, on the joint of each articulation and the distal parts of dactyli ( Fig. 38 A–E). Females similar to males in general coloration and patterning ( Fig. 38C, D ). See also Miyake (1983, 1998: pl. 12, fig. 2, as P. quadridens ) and Ko & Lee (2015: pl. 11, as P. quadridens ).

Distribution. Sea of Okhotsk including Kuril Islands, southern Sakhalin coast. Japan, pacific coast from Hokkaido to Kii Peninsula and Osaka Bay; coast of Sea of Japan from Soya Strait to Nagasaki including Peter the Great Bay ( Vinogradov 1950; Levin 1976; Griffin & Tranter 1986; Honma & Muraoka 1992; this study), Korean Peninsula ( Lee et al. 2014), North China ( Shen 1932, 1937; Dai & Yang 1991).

Habitat. Various coastal environments, from the intertidal to 80 m depth: on turfs of small red algae e.g. Ahnfeltiopsis paradoxa , Gelidium elegans , Grateloupia cornea ( Fig. 38F ), and of brown algae, e.g. Sargassum confusum , S. yezoense , Stephanocystis hakodatensis ( Fig. 38E ), among kelp forest of Eisenia bicyclis , Saccharina japonica var. diabolica etc., among seagrass beds of Phyllospadix iwatensis on rocky turfs, boulders, large mussel reefs of Mytilus galloprovincialis Lamarck, 1819 on embankment, and rarely on mud flat.

Decorating materials and epibionts. Various combinations of pieces of red, brown algae, branched colonies of bryozoans or hydrozoans. Large specimens often encrusted by sponges, bryozoans (sometimes Lichenoporidae ), hydrozoans, and barnacles.

Ecological notes. This species had been widely known to predate intensely on juveniles of Ezo Abalone, Haliotis discus hannai Ino, 1953 , and sea urchins, Mesocentrotus nudus (A. Agassiz, 1864) , and Strongylocentrortus intermedius (A. Agassiz, 1864) in captive condition ( Shiraishi 1997; Agatsuma 2001; Hoshikawa 2003, each as P. quadridens ; N. Ohtsuchi & Y. Umezu pers. obs.) and field experiment ( Kawai & Agatsuma 1996, as P. quadridens ). Laboratory observation confirmed they also predate on amphipods (H. Tamura pers. comm.) and hermit crab Pagurus middendorffii Brandt, 1851 ( Matsuo et al. 2015, as P. quadridens ).

Etymology. The species name ferox means “fierce” in Latin alluding to their positive carnivory (see above); used as an adjective.

Remarks. The present new species was discussed by Sakai (1938) as “a local variation” of Pugettia quadridens . Sakai (1938: 257, text-fig. 28) compared the specimens of P. quadridens from Iwate, Pacific coast of northeast Japan, with “typical” specimens from Shimoda, Pacific coast of southeast Japan, and regarded the former as a local variant of P. quadridens . Later, he again noted that specimens of P. quadridens from Akkeshi, Hokkaido, Pacific coast of northernmost Japan is “enormous in size, and postorbital and hepatic teeth are more or less fused together and the gastric, cardiac and intestinal regions are marked with a tubercle, while the branchial region are marked with two distinct tubercles” ( Sakai, 1976: 196). Our specimens, which include many individuals from the coast of Iwate and Akkeshi, agreed with the morphological characters mentioned by Sakai (1938: 257): “the carapace markedly broader and the hepatic lobe more or less fused with the postocular tooth as seen in the case of P. incisa , and very often they form a plate-like expansion as in that species. The tubercles on each region are well marked and the movable finger of chelipeds is uniformly denticulated throughout its whole length, not being armed with the two isolated teeth of the typical form.”. In the present new species, however, the postorbital and hepatic lobes do not form plate-like expansions as seen in P. incisa (cf. Sakai 1938: text-fig. 27) throughout their ontogeny, though they are variably fused among individuals ( Figs. 26 , 34–38 ). This disagreement is probably due to Sakai’s confusion of P. quadridens sensu lato with P. incisa (see synonymy). Our direct comparison added more morphological differences between Sakai’s P. quadridens local variant and P. quadridens sensu stricto (See Species comparisons), and therefore, we have no hesitation to separate both as distinct species.

Figures

FIGURE 25. Pugettia intermedia Sakai, 1938, coloration in life. A, B, E, adolescent males (A, B, OMNH-Ar 10700, 23.4 × 19.6 mm; E, OMNH-Ar 10701, 13.6 × 9.7 mm), Sumoto, Osaka Bay; C, D, full-grown female (OMNH-Ar 10704, 14.7 × 11.5 mm), same locality.

FIGURE 26. Pugettia ferox n. sp. Holotype, full-grown male (40.0 × 32.1 mm, NSMT-Cr 26069), Akahama, Otsuchi Bay. A, overall dorsal view; B, overall ventral view.

FIGURE 27. Pugettia ferox n. sp. Lateral view of carapace.A, holotype, full-grown male (40.0 × 32.1 mm, NSMT-Cr 26069), Akahama, Otsuchi Bay; B, allotype, full-grown female (27.9 × 22.6 mm, NSMT-Cr 26070), off Horai-jima Islet, Otsuchi Bay.

FIGURE 28. Pugettia ferox n. sp.A–C, holotype, full-grown male (40.0 × 32.1 mm, NSMT-Cr 26069), Akahama, Otsuchi Bay. A, B, anterior part of carapace, in right, dorsal (A) and left, ventral view (B); C, orbital region in lateral view (right); D, antenna (left); E, third maxilliped (left). Scales = 2.0 mm.

FIGURE 29. Pugettia ferox n. sp. holotype, full-grown male (40.0 × 32.1 mm, NSMT-Cr 26069), Akahama, Otsuchi Bay.A–C, carpus of right cheliped, dorsal (A), extensor (B), and ventral (C) surfaces; D–G, merus of right cheliped, inner (D), dorsal (E), outer (F), and ventral (G) surfaces.

FIGURE 30. Pugettia ferox n. sp., left chela in outer view. A, holotype, full-grown male (40.0 × 32.1 mm, NSMT-Cr 26069), Akahama, Otsuchi Bay; B, paratype, adolescent male (27.4 × 23.3 mm, RUMF-ZC-4975), off Horai-jima Islet, Otsuchi Bay; C, allotype, full-grown female (27.9 × 22.6 mm, NSMT-Cr 26070), same locality. Scales =5.0 mm.

FIGURE 31. Pugettia ferox n. sp., right ambulatory legs. Holotype, full-grown male (40.0 × 32.1 mm, NSMT-Cr 26069), Akahama, Otsuchi Bay. A, B, first amburatory leg, A, general appearance in upper surface; B, carpus (extensor surface); C, second ambulatory leg, carpus to dactylus (upper surface). Scales = 5.0 mm.

FIGURE 32. Pugettia ferox n. sp. A, B, full-grown, holotype male (40.0 × 32.1 mm, NSMT-Cr 26069), Akahama, Otsuchi Bay; C, D, full-grown, allotype female (27.9 × 22.6 mm, NSMT-Cr 26070), off Horai-jima Islet, Otsuchi Bay; E, full-grown, paratype female (22.8 × 18.3 mm, CBM-ZC 14880), Oarai, Kashima Sea. A, male thoracic plastron; B, male pleon; C, female sterno-pleonal cavity; D, E, female gonopore (left).

FIGURE 33. Pugettia ferox n. sp., male first and second gonopods. A–F, H, I, holotype, full-grown male (40.0 × 32.1 mm, NSMT-Cr 26069, right), Akahama, Otsuchi Bay; E–G, paratype, adolescent male (30.7 × 26.3 mm, NSMT-Cr 26071, left), same locality; J, K, large immature male (9.2 × 7.0 mm, NSMT-Cr 26), Nagane, Otsuchi Bay; A–G, first gonopod in overall mesial view (A, E), tip in mesial (B, F), lateral (C, G), upright (D) views. Scales = 1.0 mm.

FIGURE 34. Pugettia ferox n. sp. Allotype, full-grown female (27.9 × 22.6 mm, NSMT-Cr 26070), off Horai-jima Islet, Otsuchi Bay. A, overall dorsal view; B, overall ventral view.

FIGURE 35. Pugettia ferox n. sp., overall habitus. A, B, paratype, adolescent male (19.8 × 14.7 mm, CBM-ZC 14880), Oarai, Kashima Sea; C, D, paratype, adolescent female (15.4 × 11.6 mm, CBM-ZC 14880), same locality.

FIGURE 36. Pugettia ferox n. sp., overall habitus. A, B, paratype, immature male (8.8 × 6.2 mm, NSMT-Cr 26071), Tomarihama, Oshika Peninsula; C, D, paratype, immature female (10.1 × 7.2 mm, NSMT-Cr 26071), same locality. A, C, dorsal view; B, D, ventral view.

FIGURE 37. Individual variation of Pugettia ferox n. sp. A, full-grown male (18.1 ×14.9 mm, not fully hardened, ZMUC- CRU-20232, examined in Griffin & Tranter 1986 as P. quadridens), Nagasaki, Kyushu; B, adolescent male (17.8 × 13.1 mm, OMNH-Ar 6023, examined in Ariyama 1995 as P. q. quadridens), Osaka Bay; C, adolescent male (22.8 × 18.3 mm, NSMT-Cr 26073), Akkeshi, Hokkaido; D, full-grown male (22.1 × 17.8 mm, CBM-ZC 14881), Tomarihama, Oshika Penninsula; E, fullgrown male (39.3 × 33.9 mm, NSMT-Cr 26073), Akkeshi, Hokkaido. Legs electrically removed in C–E.

FIGURE 38. Pugettia ferox n. sp., coloration in life. A–E, full-grown, paratype male (A, B, E, NSMT-Cr 26072, 25.1 × 20.1 mm) and female (C, D, NSMT-Cr 26072, 17.2 × 13.6 mm), from Sargassum yezoense beds, at Akahama, Otsuchi Bay, on 24 January 2017; F, full-grown female, from Ahnfeltia paradoxa turfs near low tidal mark at Oarai, Kashima Sea, on 8 May 2012.

FIGURE 39. Relationships of relative length of hepatic lobe (HpL/PoL) against post-pseudorostral carapace length (PCL) in Pugettia quadridens (De Haan, 1837), P. intermedia Sakai, 1938, P. ferox n. sp., P. pellucens Rathbun, 1932, and P. vulgaris Ohtsuchi, Kawamura & Takeda, 2014.