Paguristes doederleini, Komai, 2001

Komai, 2001, review of the north-western Paci ® c species of the genus Paguristes Decapoda: Anomura: Diogenidae), I. Five species initially reported Ortmann (1892) from Japan, Journal of Natural History 35 (3), pp. 357-428 : 415-425

Paguristes doederleini sp. nov.

(®gures 28±31)

Paguristes setosus: Ortmann, 1892: 281 , pl. 12, ®gure 9; Makarov, 1938: 167, ®gure 67; 158, ®gure 67. Not Paguristes setosus (H. Milne Edwards, 1848) .

Paguristes setosus: Alcock, 1905: 156 (part); Gordan, 1956: 324 (part).

Paguristes kagoshimensis: Balss, 1913: 40 . Not Paguristes kagoshimensis Ortmann, 1892 [5 Paguristes digitalis Stimpson, 1858 ].

Paguristes puniceus: Miyake, 1978: 37 (part). Not Paguristes puniceus Henderson, 1896 .

Paguristes incomitatus: Miyake, 1978: 41 (part).

Material examined. HOLOTYPE. OOE Katsuyama Ukishima Islet, Uchibo coast of Boso Peninsula, 150±200 m; 10 April 1997; gill net for scampi; coll. T. Komai; male (SL 6.8 mm); CBM-ZC 4907.

PARATYPES. OOE Shionomisaki , Kii Peninsula, 300 m; October 1996; dredge; coll. S. Nagai; one female (SL 6.6 mm), parasitized by rhizocephalan; CBM-ZC 3563. Data as for holotype; three males (SL 5.0± 5.6 mm), one female (SL 4.7 mm); CBM-ZC 4908. OOE Tateyama Bay , Boso Peninsula, 35ss00.57¾N, 139ss41.45¾E , 100± 258 m; TRV Shin’yo-maru cruise to Izu Islands , stn 16; 24 October 1996; dredge; coll. T . Komai; one male (SL 3.2 mm); CBM-ZC 4909. Okinoyama Bank , Sagaminada , 35ss00.07¾N, 139ss40.30¾E, 98±100 m; TRV Shin’ yo-maru cruise to Izu Islands, stn 18; 24 October 1996; dredge; coll. T . Komai; one ovigerous female (SL 3.0 mm); CBM-ZC 4910. Same data as CBM-ZC 4909; two males (SL 3.5, 4.2 mm), one ovigerous female (SL 3.4 mm); CBM-ZC 5226. Goronba , Sagami Bay , 110±200 m; 21 January 1958; one female (SL 3.7 mm); reported by Miyake (1978) as Paguristes puniceus , det. no. 198; NSMT-CrR 1413. Amadaiba , 110±150 m; 17 January 1958; one male (SL 4.9 mm); reported by Miyake (1978) as P. puniceus , det. no. 216; NSMT-CrR 1480. 4 km westsouth-by-west of Jogashima Islet , 20±195 m; 13 February 1966; one male (SL 4.7 mm); reported by Miyake (1978) as P. puniceus , det. no. 611; NSMT-CrR 2395. Higashi-Ohne , Sagami Bay , 120 m; 13 June 1968; one male (SL 6.0 mm); reported by Miyake (1978) as P. puniceus , det. no. 349; NSMT-CrR 3592. 3 km oOE westsouth-by-west of Jogashima Islet , Sagami Bay , 90±95 m; 13 March 1971; one male (SL 5.9 mm); reported by Miyake (1978) as P. puniceus , det. no. 683; NSMT-CrR 3718. OOE 2 km south-west of Kamegisho , Sagami Bay , 100±150 m; 17 March 1961; one female (SL 4.3 mm); reported by Miyake (1978) as Paguristes incomitatus , det. no. 431; NSMT-CrR 1879. Sagami Bay , 180 m; 1881; coll. L. DoÈderlein; two males (SL 4.9, 7.3 mm); reported by Ortmann (1892) as Paguristes setosus ; MZS 398 (spirit) . Sagami Bay , 500 m (stn 16); 1904±1905; coll. F. Doēin; one male (SL 5.9 mm); reported by Balss (1913) as Paguristes kagoshimensis, No. 2464 ; ZSM 234 /1.

Description. Thirteen pairs of biserial phyllobranchiae.

Shield (®gure 28A) 1.1±1.2 times longer than broad; anterolateral margins sloping; anterior margin between rostrum and lateral projections concave; posterior margin truncate; dorsal surface rugose with low, irregular elevations on gastric region either side of mid-line and scattered small spines and tufts of long setae laterally. Rostrum short, triangular, weakly curved ventrally, slightly falling short of or slightly over-reaching lateral projections; terminating bluntly, with setae distally; dorsal surface with broad median elevation; lateral margins smooth. Lateral projections obtusely triangular, occasionally with small marginal spine. Branchiostegites (®gure 28C) calci®ed anteriorly and dorsally, anterior margins each with few small spines.

Ocular peduncles (®gure 28A) moderately slender (5.5±6.0 times longer than width of cornea), about 0.6±0.7 times as long as shield, cylindrical, weakly ināted basally, cornea not dilated; dorsal surfaces each with tuft of long setae proximally. Ocular acicles subtriangular, terminating in simple, sometimes elongate, acute spine or two small spines; mesial margins unarmed, lateral margins unarmed or armed with one small spinule; separated by 0.5±0.7 basal width of one acicle.

Antennular peduncles (®gure 28A, B) when fully extended slightly overreaching distal margins of corneas by 0.3±0.5 length of ultimate segment. Ultimate segment moderately slender, about 1.4±1.5 times longer than penultimate segment, unarmed, with row of sparse long setae on dorsal surface. Penultimate segment without ventral spine. Basal segment with spine on dorsolateral margin of statocyst lobe, laterodistal margin with spinule, ventromesial distal angle produced, terminating in acute spine.

Antennal peduncles (®gure 28A, C) moderately short, reaching 0.7±0.8 length of ocular peduncles by distal margin of ®fth segment; with supernumerary segmentation. Fifth segment unarmed. Fourth segment occasionally with small spine at dorsodistal margin. Third segment with ventromesial distal angle strongly produced, terminating in strong spine. Second segment with dorsolateral distal margin weakly produced, terminating in small simple or bi®d spine, lateral margin with few small spines and tufts of long setae, mesial margin unarmed; dorsomesial distal angle with small spine, mesial half elevated. First segment with unarmed laterodistal margin, lateral face unarmed; ventromesial distal margin strongly produced, but unarmed. Antennal acicles moderately long, slightly falling short of distal margin of ®fth segment, with numerous long setae; terminating in strong simple or bi®d spine; ināted basally; mesial margin with two to four strong spines proximally, lateral margin unarmed or with one to three small to strong spines distally. Antennal ¯agella (®gure 28D) 1.4±1.5 times longer than shield, not exceeding tips of chelipeds, composed of 20±25 articles; with long setae on distal margin every three articles.

Endopod of maxillule (®gure 28E) broad, without bristle on mesial margin; internal lobe distinctly produced, with ®ve bristles on rounded distal margin; external lobe very well developed, elongate, strongly recurved, distolateral corner with ®ve setae. Third maxilliped (®gure 28F) with basis and ischium partially fused; ischium (®gure 28G) with well developed crista dentata, composed of moderately slender corneous teeth, ventrodistal margin with one spine but dorsolateral corner unarmed; merus with three to ®ve moderately strong spines, becoming weaker distally, dorsodistal margin unarmed; carpus unarmed on dorsodistal margin; dactyl moderately short.

Chelipeds (®gure 29A±D) moderately short, equal or slightly subequal with left cheliped stouter. Chela subtriangular in dorsal view, 1.9±2.1 times longer than wide. Dactyl 2.0±2.3 times longer than palm; cutting edge with row of small calcareous teeth in proximal 0.7±0.8 and row of strong corneous teeth in distal 0.2±0.3, terminating in strong corneous claw; overlapped by ®xed ®nger; dorsomesial margin with row of moderately small, conical, corneous-tipped spines, decreasing in size distally, dorsal surface with some moderately small corneous-tipped spines and spinulose tubercles proximally and scattered tufts of long stiOE setae; mesial face protuberan t ventrally, with scattered numerous corneous-tipped spinules or corneous spinules and scattered tufts of short setae; ventral surface unarmed, with tufts of stiOE setae. Palm distinctly shorter than carpus; dorsomesial margin with three or four strong, corneous-tipped spines, dorsal surface sloping to lateral surface without delineation of dorsolateral margin, with several irregular rows of moderately strong, corneous-tipped spines, decreasing in size on ®xed ®nger; mesial surface with few low protuberances, accompanied by tufts of long setae, mesiodistal margin unarmed; lateral surface with scattered spinulose tubercles and few tufts of stiOE setae; ventral surface well ināted, with row of spinulose tubercles accompanied by tufts of long setae on midline, extending onto ®xed ®nger, and few protuberances or tubercles laterally and mesially. Fixed ®nger not noticeably deēxed; lateral margin with row of moderately strong corneous-tipped spines, decreasing in size distally; ventral face somewhat depressed at base; cutting edge with row of small calcareous teeth in distal 0.7±0.8, terminating in strong corneous claw; with narrow hiatus when closed. Carpus about 0.7±0.8 times as long as merus; dorsomesial margin with row of four or ®ve strong, conical, corneous-tipped spines, increasing in size distally; dorsal surface with single or double row of moderately strong, corneous-tipped spines in midline and scattered tufts of long setae, dorsodistal margin produced, occasionally with moderately small spine laterally; dorsolateral margin with row of moderately strong spines, increasing in size distally; mesial surface with low protuberances and tufts of setae along dorsal and distal margins; lateral surface with some scattered moderately small tubercles, accompanied by tufts of setae dorsally, laterodistal margin with few small spines dorsally; ventral face unarmed. Merus moderately deep; dorsal surface with row of small spinulose tubercles accompanied by tufts of long setae, and subdistal, spinulose transverse ridge, extending onto lateral and mesial faces, dorsodistal margin with row of small spines (one spine occasionally enlarged); mesial surface nearly smooth, with few very short setae, ventromesial margin with row of moderately strong, corneous-tipped spines and sparse setae; lateral surface with scattered small tubercles and very short setae, ventrolateral margin with small spine near distal corner and small tubercles in proximal 0.8; ventral face unarmed, with short to long setae. Ischium with row of small spinulose tubercles, increasing in size distally, on ventromesial margin, ventrolateral distal angle with small spine. Coxa unarmed.

Second pereopods (®gure 30A, B) moderately long. Dactyls long, 1.5±1.7 times longer than propodi; weakly curved in lateral view, nearly straight or slightly twisted in dorsal view; terminating in strong, curved, corneous claw; dorsal surfaces each with row of small to moderately small corneous-tipped spines, becoming smaller distally, partially obscured by numerous tufts of long setae; mesial faces each with two rows of tufts of setae dorsally and ventrally and few small corneous spines proximally; lateral faces with two sparse rows of tufts of setae dorsally and ventrally; ventral surfaces each with row of 20±25 small corneous spines, increasing in size distally, ¯anked by two rows of tufts of long stiOE setae. Propodi distinctly longer than carpi; dorsal surfaces each with row of strong, corneous-tipped spines mesially, partially obscured by tufts of long setae, dorsodistal margins each with prominent spine; mesial surfaces with scattered tufts of long setae and two irregular rows of rounded, often vertically elongate, protuberances ventrally; lateral surfaces each with row of low protuberances, accompanied by tufts of long setae near dorsal and ventral margins and tufts of short setae on midline; ventral surfaces each with row of low protuberance s bearing corneous spinules and tufts of long setae, ventrodistal margins each with row of small corneous spinules. Carpi moderately long; dorsal surfaces each with double row of strong, corneous-tipped spines mesially and tufts of long setae; mesial surfaces nearly smooth, with few very short setae; lateral faces strongly convex, each with shallow longitudinal sulcus lined with tufts of stiOE setae and submedian row of tufts of stiOE setae; ventral surfaces with few short setae, ventrodistal margins with long setae. Meri strongly compressed laterally; dorsal surfaces each with row of spinules laterally in proximal half and numerous long setae; mesial surfaces with few tufts of setae; lateral surfaces with few small spinulose tubercles dorsally and ventrally; ventral surfaces each with row of small spines or spinules mesially and numerous long setae, both ventromesial distal and ventrolateral distal margins unarmed. Ischia with spinule and numerous setae on dorsal surfaces; ventral surfaces with row of spinules mesially and numerous setae. Coxae unarmed.

Third pereopods (®gure 30C, D) generally similar to second in setation. Dactyls with single or double row of small corneous spines on dorsal surfaces mesially; mesial surfaces each with single or double row of small corneous spines ventral to midline; ventral surfaces each with row of 20±25 small corneous spines, ¯anked by two rows of tufts of long setae. Propodi protuberant on dorsal surfaces, sometimes with few small corneous spinules distally; mesial surfaces with few sparse small corneous spines on midline and irregular double row of rounded protuberances ventrally, obscured by numerous tufts of long setae; ventral surfaces protuberant. Carpi each with dorsodistal spine and occasionally additional small spine on dorsal surface; mesial faces with few tufts of setae; lateral surfaces each with small subdistal spine. Meri with few spinules on dorsal surfaces proximally; mesial surfaces unarmed; lateral surfaces with few tufts of short setae; ventral surfaces slightly protuberant, ventromesial distal and ventrolateral distal margins smooth, unarmed. Coxa unarmed on dorsal and ventral margins; females with paired gonopores.

Fourth pereopods (®gure 28H) thickly setose on dorsal and ventral faces. Dactyl (®gure 28I) weakly curved, terminating in strong corneous claw; dorsal surface unarmed; ventral surface with row of four or ®ve corneous teeth laterally and slender membraneous tube-like preungual process arising from base of claw. Propodus moderately stout, with nearly straight ventral margin; dorsal surface unarmed; propodal rasp composed of three or four rows of small corneous scales, fewer proximally, extending to 0.7 ±0.8 length of ventral margin. Carpus with moderately strong dorsodistal spine.

Fifth pereopods chelate, setose. Coxae in males each with gonopore.

First and second pleopods in males paired, modi®ed. First pleopod (®gure 31A±C) with double or triple row of long setae on mesial face of basal segment. Inferior lamella strongly twisted, with blunt longitudinal ridge on ventral surface, continuous with proximolateral margin; distal margin broadly rounded, with single row of moderately strong, hooked corneous spines; mesial margin with numerous bristles. External lobe well developed, broadly rounded distally, distinctly over-reaching inferior lamella. Internal lobe large, rounded, separated from external lobe by wide notch; margins with thick, long setae.

Second pleopod (®gure 31D, E) with basal segment somewhat ¯attened, with few setae proximally. Endopodite ¯attened, weakly twisted, margins bluntly edged, with row of long setae on ventrolateral margin and one plumose seta at midlength of dorsal margin; tuft of stiOE setae at ventrodistal angle. Appendix masculina moderately broad, slightly twisted, not noticeably elongate distally; articulation suture discernible only on mesial face; distal margin rounded; exterior (lateral) surface faintly sulcate, with numerous short to long bristles dorsally and distally; ventral margin convex, without bristles or setae in proximal 0.3; interior (mesial) face not sulcate, with few bristles near dorsal margin.

Third to ®fth pleopods of males unpaired, exopods very well developed, endopods rudimentary.

Females with ®rst pleopods (®gure 31F) paired; articulation between basal and distal segments obscure; basal segments not ināted basally; distal segment as broad as and slightly longer than basal segment. Second to ®fth pleopods unpaired; second to fourth pleopods with both rami well developed, exopods much longer than endopods, multiarticulated, endopods incompletely biarticulated; ®fth pleopod much shorter than preceding pleopods, with exopod well developed, not articulated, endopod vestigial.

Brood pouch (®gure 31G) moderately large, subtriangular, margins smooth, with long plumose setae. Second and third abdominal tergites moderately calci®ed on left, contiguous, with moderately long setae on left margins; fourth abdominal tergite widely separated from third tergite, with moderately long setae.

Uropods strongly asymmetrical; protopods each with few small corneous-tipped spines on posteroventral margin.

Telson (®gure 28J) with posterior lobes somewhat asymmetrical, left larger than right; generally rounded; separated by deep, narrow median cleft; transverse indentations deep; terminal margins rounded, left with six strong spines, right with ®ve or six weaker spines. Anterior lobes unarmed on lateral margins.

Coloration. In life: shield generally orange±red, paler on gastric region. Ocular peduncles solid orange ±red. Ultimate segment of antennule light yellow to light orange; penultimate and basal segments with tinge of red dorsally. Antennal peduncles generally orange ±red; ®fth segment light orange; ¯agella light orange or yellow, without bands. Chelipeds generally orange ±red, spines or tubercles paler. Ambulatory pereopods generally orange ±red; dactyls becoming paler distally; propodi and meri white distally.

Size. Largest male: SL 7.3 mm; largest female: SL 6.6 mm; ovigerous female: SL 3.0 mm.

Habitat. Gastropod shells.

Distribution. Known only from the Paci®c coast of Japan from Boso Peninsula to Kii Peninsula; 90 ± 500 m.

Etymology. The species is named for Ludwig DoÈderlein in recognition of his contributions to the study of the marine fauna of Japan.

Remarks. The presence of strong spines on the terminal margins of the telson provides evidence that this new species should be placed in group A of the genus ( McLaughlin and Provenzano, 1974b). This new species appears close to P. puniceus Henderson, 1896 , P. incomitatus Alcock, 1905 , and P. miyakei Forest and McLaughlin, 1998 . From P. puniceus , it diOEers in the shorter, less setose antennal ¯agellum and the presence of a median row of spines on the carpus of the cheliped. The less setose shield and the longer antennal ¯agella separate P. doederleini from P. incomitatus . According to Alcock (1905), the shield of P. incomitatus is tomentose, the hairs, which are not long, are matted into little tufts with sand and mud. The antennal ¯agellum is 1.4±1.5 times longer than the shield in P. doederleini , while it is shorter than the shield in P. incomitatus . The new species is immediately distinguished from P. miyakei by the shorter antennular peduncles, much more setose mesial faces of the ambulatory propodi and the presence of a ventral row of small corneous spines on the mesial faces of the dactyls of the third pereopods.

As reported by Forest and McLaughlin (1998), Paguristes setosus (H. Milne Edwards, 1848) , a species endemic to New Zealand, has been a source of taxonomic confusion for more than 150 years. It was brie¯y described by H. Milne Edwards (1848) only as very similar to Paguristes pilosus (H. Milne Edwards, 1836) ; the type locality was indicated as New Guinea. The ensuing confusion over the true identity of P. setosus was initiated in part by H. Milne Edwards himself through his incorrect indication of New Guinea as the type locality of the species, and additional misinterpretations and errors by virtually all subsequent authors have compounded the problem. Ortmann (1892) recorded P. setosus from Sagami Bay, and later Yokoya (1933) and Miyake (1978) have identi®ed particular specimens from Japanese waters as this species. Although Ormtann’s (1892: pl. 12, ®gure 9) illustration of the shield and cephalic appendages is very diagrammatic, his description clearly showed that he was not dealing with true P. setosus as he stated that the chelipeds were similar. In P. setosus , the chelipeds are greatly dissimilar with the left being much larger than the right (H. Milne Edwards, 1848; Forest and McLaughlin, 1998). Yokoya (1933) reported P. setosus from several localities around Japan but provided only a reference to Ortmann’s description and ®gure. Makarov (1938; 1962) paraphrased Ortmann’s German text and reproduced Ortmann’s illustration ( Makarov, 1938: 167, ®gure 67; 1962: 158, ®gure 67), but indicated that he had no personal knowledge of the species. Miyake (1978: 27, text-®gure 8a,b) presented a rather detailed description of a species he referred to Paguristes setosus . Forest and McLaughlin (1998) re-examined four of ®ve specimens examined by Miyake (1978), and they established a new species, P. miyakei , for three of the four specimens. Although they suggested that the fourth specimen conceivably might be P. setosus sensu Ortmann (1892) , its taxonomic status remained undetermined. The fourth specimen was said to be diOEerent from P. miyakei but was consistent with Ortmann’s P. setosus in the antennular peduncles that overreached the distal margins of the corneas by only half the length of the ultimate segment, rather than by nearly the entire length of that segment.

I have been able to examine the two male specimens identi®ed as P. setosus by Ortmann (1892) in the collection of the MuseÂe Zoologique, Strasbourg ( MZS 398). The two specimens are clearly diOEerent from P. miyakei . They are referred to P. doederleini described herein. I have re-examined the small male specimen reported by Miyake (1978) as P. setosus and subsequently examined by Forest and McLaughlin (1998) (NSMT-CrR 860; Miyake det. no. 84) and found that the specimen actually represents P. brachytes Komai, 1999 .

The present study has also shown that the male specimen identi®ed as P. kagoshimensis by Balss (1913: 40) ( ZSM 234/1) actually represents P. doederleini . Additionally, during the re-examination of Miyake’s (1978) material of Paguristes , I have found that three species, including P. doederleini , were confounded as P. puniceus Henderson, 1896 . Eleven of the 16 specimens have been available to me for re-examination. The following ®ve specimens are referable to P. doederleini : NSMT-CrR 1413, 1480, 2395, 3592 and 3718 (see Material examined). The ovigerous female NSMT-CrR 2968 (Miyake det. no. 616) is P. miyakei , and it closely ®ts Miyake’s (1978) text-®gure 39a±d. The ®ve male specimens, NSMT-CrR 909 (Miyake det. no. 103), 939 (no. 108), 979 (no. 119), 981 (no. 121) and 1583 (det. no. 611) belong to an undescribed species, which is similar to Paguristes japonicus Miyake, 1961 . The description of the colour given by Miyake is consistent with P. doederleini . It has been revealed that a female specimen identi®ed as Paguristes incomitatus by Miyake (1978) (NSMT-CrR 1879; Miyake det. no. 431) also belongs to P. doederleini (see Material examined).

Miyake (1978) proposed an informal P. setosus species group for the species characterized by the relatively long antennal ¯agellum, which is subequal to or longer than the carapace, the absence of spines on the terminal margins of the telson, and the presence of closely-set spinules on the distal margin of the inferior lamella of the male ®rst pleopod. However, as discussed above, P. setosus sensu Miyake (1978) possesses spines on the terminal margins of the telson, and thus the name of the group proposed by Miyake (1978) will lead to confusion. Further, Miyake’s group agrees with group B of McLaughlin and Provenzano (1974b), which is characterized by the absence of spines on the terminal margins of the telson. In order to avoid needless confusion, Miyake’s species group name should not be used.