Pachygrapsus laevimanus Stimpson, 1858

Poupin, Joseph, Davie, Peter J. F. & Cexus, Jean-Christophe, 2005, A revision of the genus Pachygrapsus Randall, 1840 (Crustacea: Decapoda: Brachyura, Grapsidae), with special reference to the Southwest Pacific species, Zootaxa 1015 (1), pp. 1-66: 18-22

publication ID

http://doi.org/ 10.11646/zootaxa.1015.1.1

publication LSID

lsid:zoobank.org:pub:67DBD7AA-FA11-4F32-811B-0A9EFF4C668F

persistent identifier

http://treatment.plazi.org/id/6C3D8794-ED56-FFEE-6C1C-FD20FC6DFE40

treatment provided by

Felipe

scientific name

Pachygrapsus laevimanus Stimpson, 1858
status

 

Pachygrapsus laevimanus Stimpson, 1858   ( Figures 5a–f View FIGURE 5 , 14b View FIGURE 14 , 15b View FIGURE 15 , 16 View FIGURE 16 )

Pachygrapsus laevimanus Stimpson, 1858: 48   [102] [type locality: Port Jackson, Sydney, Australia] — Stimpson, 1907: 117 (New South Wales). — Holthuis & Gottlieb, 1958: 102 (New South Wales). — Davie, 1998b: 151, photograph (Queensland); 2002: 218 (Queensland, New South Wales, Norfolk I.). — Poore, 2004: 508, fig. 161d, h, 162b (Queensland, New South Wales, Victoria).

Pachygrapsus transversus   — Rathbun, 1907: 29 (Easter I.); 1918: 248 (part, only specimens from Sydney and Easter I.). — Garth, 1973: 324 (Easter I). — Báez & Ruiz, 1985: 105 (Easter I.). [Not P. transversus ( Gibbes, 1850)   ]

Type material

Male neotype 18.0 x 21.7 mm ( AM P7478), herein designated. Pachygrapsus laevimanus   was poorly described by Stimpson (1858) from specimens collected in the vicinity of Sydney. Most of Stimpson’s collections, including the types of P. laevimanus   , were lost in the Chicago fire of 1871. As a result, this species has been ignored for many years and often confused with P. transversus ( Gibbes, 1850)   , a species widely distributed in the Mediterranean, east and west Atlantic, and east Pacific. Because of this long period of confusion, and because even now there is uncertainty over the identity of specimens from Easter I. (see below), we believe that it is necessary to erect a neotype for P. laevimanus   to ensure the future stability of this taxon.

Material Examined

Neotype. Australia. New South Wales: Sydney, 33°52’S, 151°15.5’E, on reef, Rose Bay, Port Jackson , coll. Mel Ward, September 1924, 1 M 18.0 x 21.7 mm ( AM P7478). GoogleMaps  

Other specimens. Australia. New South Wales: Sydney, Manly , leg from AM, 3 M 6.2 x 7.9–8.3 x 10.2 mm, 1 F 6.8 x 8.4 mm ( USNM 43776 View Materials )   ; Sydney , November 1926, among small stones in rock crevices, between tides marks, 1 M 10.6 x 12.6 mm, 1 ov. F 8.5 x 10.6 mm, 1 F 8.0 x 10.0 mm ( MNHN B11083 View Materials ; leg from AM P5D07, part)   ; Sydney, Balmoral Beach, Mosman , coll. L. B. Holthuis, 23 April 1955, 5 M 7.9 x 9.6–12.0 x 14.7 mm, 5 F 6.3 x 7.9–9.6 x 12.1 mm ( RMNH 10424 View Materials )   ; Sydney, Port Jackson , bottle and glass rocks, intertidal under stone and weed, 33°50.9’S, 151°16.2’E, coll. D. J. G. Griffin, 23 October 1968, 1 M 6.7 x 8.4 mm, 1 F 7.0 x 8.7 mm, 1 juv. 3.9 x 4.9 mm, ( AM P17802 View Materials ) GoogleMaps   ; Sydney, Long Bay Coast, rocky reef, between tide marks, purchase #78 S. Kellner, 3 M 6.3 x 7.4– 7.5 x 9.1 mm, 1 ov. F 5.8 x 7.3 mm ( USNM 98830 View Materials )   ; Sydney , ‘ Maulyi’, AM acc. n° 25661, coll. 3 February 1889, 2 M 8.5 x 10.5, 10.5x12.5 ( UNSM 17054 View Materials )   ; Twofold Bay, Murrumbulga point, 37°04.7’S, 149°53.1’E, intertidal rock platform, coll. S. Keable, 25 July 1985, 3 M 7.5 x 9.1–11.9 x 14.7 mm, 2 F 8.0 x 10.1, 9.7 x 12.1 mm ( AM P36075 View Materials ) GoogleMaps   ; mouth of Clarence R., 29°26’S, 153°22’E, coll. A. A. Cameron, 1 ov. F 11.3 x 14.2 mm ( QM W3306) GoogleMaps   . — Lord Howe I.: 31°31’S, 159°04’E, Neds Beach, coll. G. Kelly, 14 September 2003, 5 M 9.6 x 11.7–12.1 x 14.4 mm, 1 ov. F 11.8 x 14.0 mm ( QM W26879 View Materials ) GoogleMaps   ; 31°31’S, 159°04’E, Neds Beach, coll. G. Kelly, 30 August 2003, 1 M 14.3 x 17.4 mm ( QM W26876 View Materials ) GoogleMaps   . — Queensland: Caloundra, Kings Headland , 26°48’S, 153°08’E, rocky shore, under rocks, coll. J. W. Short, M. Bavins, October 1996, 3 F 8.5 x 10.4–13.8 x 16.8 mm ( QM W21818 View Materials ) GoogleMaps   ; Kings Headland , 26°48’S, 153°09’E, rocky shore, under rocks, coll. J. W. Short, 27 September 1996, 1 F 8.7 x 10.5 mm ( QM W21533 View Materials ) GoogleMaps   ; Kings Headland, N. end, Kings Beach , 26°48’S, 153°08’E, rocky shore, coll. M.S.A. party (Brisbane Shell Club), 13 March 1983, 1 F 7.6 x 9.3 mm ( QM W10457 View Materials ) GoogleMaps   ; Kings Headland , 26°48’S, 153°08’E, rocky shore, coll. P. Davie, D. Potter, 30 July 1997, 2 M 11.6 x 14.6, 11.3 x 13.3 mm ( QM W23937 View Materials ) GoogleMaps   ; Moreton Bay , 27°00’S, 153°00’E, 2 M 11.3 x 13.3, 14.7 x 17.9 mm ( QM W12336 View Materials ) GoogleMaps   . — Tasman Sea. Middleton reef: 29°28.5’S, 159°03.7’E, reef flat near wreck of Runic, rubble, dead coral heads, dead Tridacna   , low tide, coll. J. K. Lowry, 4 December 1987, 9 M 3.5 x 4.6–10.3 x 12.9 mm, 7 ov. F 4.5 x 5.8–7.9 x 9.8 mm, 6 F 5.9 x 7.6–8.7 x 11.0 mm ( AM P38221 View Materials ) GoogleMaps   ; 29°25’S, 159°00’E, near wreck of Runic, coll. J. W. Short, R. J. McKay, 9 May 1987, 1 M 10.6 x 13.2 mm ( QM W13048 View Materials ) GoogleMaps   , 1 M 7.1 x 9.2 mm ( QM W13050 View Materials )   . — Elizabeth reef, 29°55.4’S, 159°02.7’E, sand cay, north west lagoon entrance, under stone, low tide, coll. J. K. Lowry, 12 December 1987, 12 M 7.9 x 9.8–11.7 x 14.2 mm, 5 ov. F 6.5 x 8.0–8.2 x 10.2 mm, 4 F 8.3 x 9.8–10.0 x 12.7 mm ( AM P38223 View Materials ) GoogleMaps   ; 29°55’S, 159°00’E, coll. J. W. Short, 6 May 1987, 1 M 12.4 x 14.9 mm ( QM W13051 View Materials ) GoogleMaps   , 4 May 1987, 4 M 4.8 x 5.9–14.3 x 17.4 mm ( QM W13047 View Materials )   .

Norfolk I.: Cemetery Bay , under stones on intertidal rock platform, coll. D. J. G. Griffin, 30 March 1969, 1 M 5.4 x 7.0 mm, 1 F 6.7 x 8.7 mm ( AM P17329 View Materials )   .

Austral Is.: Rapa I., Haurei Bay , intertidal, RV Marara   campaign, coll. J. Poupin, 19 to 21 March 1995, 13 M 6.6 x 7.8–14.0 x 16.8 mm, 4 ov. F 8.0 x 10.0–11.1 x 13.9 mm, 4 F 8.1 x 10.3–13.9 x 17.0 mm ( MNHN B29265 View Materials )   . — BENTHAUS Expedition: Haurei Bay , intertidal, near wharf, among stones and rubbles, coll. J. Poupin, 2 November 2002, 14 M 4.0 x 5.0–14.8 x 17.5 mm, 7 ov. F 6.6 x 8.0–12.8 x 16.0 mm, 7 F 7.1 x 8.6–11.3 x 13.6 mm ( MNHN B29266 View Materials )   ; Haurei Bay , intertidal, coll. A. Warén, 8 November 2002, 2 F 6.3 x 7.7, 6.6 x 7.9 mm ( MNHN B29267 View Materials )   ; 27°37.4'S, 144°18.4’W, north of Anatakuri Bay , 2 m, in sediment under stones, coll. malacologist team, stn 38, 22 November 2002, 1 M 6.3 x 7.6 mm ( MNHN B29268 View Materials ) GoogleMaps   ; Anarua Bay , 27°36.4’S, 144°22.6’W, intertidal, coll. malacologist team stn 87 (possibly 86), 25 November 2002, 1 juv. 2.6 x 3 mm ( MNHN B29269 View Materials ) GoogleMaps   .

Easter I.: shore, coll. RV Albatross, 16 December 1904, 1 F 7.6 x 9.5 mm (UNSM 33186; see remarks).

Description

Carapace 1.2–1.3 times broader than long ( Fig. 5a View FIGURE 5 ). Dorsal surface slightly convex on anterior half, covered with strong transverse striae, smooth or with scarce setae. Median postfrontal lobes distinct, striated; mesogastric, cardiac regions with few short striae (sometimes indistinct on cardiac region); intestinal region flat, almost totally smooth. Lateral margins of carapace convex, slightly convergent posteriorly, armed with single conspicuous tooth posterior to exorbital tooth. Front 0.6 times exorbital width ( Fig. 5b View FIGURE 5 ); anterior margin sinuous, granulate, with shallow sinuses. Orbits subrectangular in dorsal view, about one third as wide as front; infraorbital margin minutely dentate, separated by deep notch from outer orbital tooth ( Fig. 14b View FIGURE 14 ).

Chelipeds equal. Merus striated transversely, inner ventrodistal lobe denticulated, with 2–6 distinct teeth. Carpus smooth on upper surface; with blunt tooth at inner distal angle. Chelae robust, height about half length ( Fig. 5c View FIGURE 5 ). Upper margin rounded, with faint oblique striae proximally, on inner side. Outer face smooth, regularly convex; smaller specimens with weak longitudinal line on outer face of fixed finger, near lower margin. Inner surface of palm smooth. Fingers about two third as long as palm, narrowly gaping, tip corneous, spoon­like, glabrous. Cutting margin of fixed finger with 6–7 triangular teeth, larger medially; moveable finger with 3–4 triangular teeth proximally.

Ambulatory legs robust. Meri with faint transverse ridges on outer surfaces; upper margins with few moveable spines on distal half; P2–P4 with strong dorsodistal tooth, dorsodistal angle of P5 rounded or only with small tooth; lower margins unarmed except for 2–3 spines at distal angles. Dactyli slightly curved, armed with several long moveable spines, terminating in strong corneous claw. P2 propodus with row of setae on dorsal margin. P3 propodus with conspicuous brush of setae on dorsal margin ( Fig. 5d View FIGURE 5 ); on some specimens this brush may be poorly developed or even missing. Lower margin of P5 merus slightly denticulate, usually without sub­median tubercle ( Fig. 5e View FIGURE 5 ), except on few of smallest specimens (less than 8 x 10 mm).

Abdominal tergites and thoracic sternites smooth ( Fig. 5f View FIGURE 5 ). Sixth somite of abdomen plus telson triangular in male. G1 ( Fig. 15b View FIGURE 15 ) stout with distal process horn­like, strongly curved.

Colour: live colour is dark brown to black, slightly paler along transverse striations, often with paler cardiac and intestinal regions and a few small paler patches surrounding the metagastric region; chelae with inner face becoming lighter in colour ventrally and distally with tips of fingers pale.

Measurements: medium size; carapace of specimens examined ranging from: males 3.5 x 4.6–18.0 x 21.7 mm; females 4.5 x 5.8–13.9 x 17.0 mm; smallest ovigerous female was 4.5 x 5.8 mm.

Distribution

Eastern Australia (New South Wales, southern Queensland, Victoria); Tasman Sea (Middleton and Elizabeth Reefs), Norfolk and Lord Howe islands   ; French Polynesia, Austral Is. (Rapa I.);? Easter I. Between latitude 26– 37°S, longitude 149°E – 144°W ( Fig. 16 View FIGURE 16 ) GoogleMaps   .

Habitat

Found in the intertidal zone among small rocks and stones, dead coral, rubble, and seaweeds.

Remarks

Pachygrapsus laevimanus   is morphologically close to P. transversus ( Gibbes, 1850)   of similar size, especially in the shape of the carapace and chelae. The setation of the ambulatory legs, however, differs conspicuously between the two species. There is a brush of setae on the P2 propodus in P. transversus   (obvious in females only), whereas it is located on P 3 in P. laevimanus   . The shape of the G1 is also very different between the two species, with the tip slender and petal­like in P. transversus   instead of stout and horn­like in P. laevimanus   ( Fig. 15b, l View FIGURE 15 ).

Pachygrapsus laevimanus   was poorly described by Stimpson (1858) from specimens collected in the vicinity of Sydney. As a result, this species was ignored for many years and often confused with P. transversus ( Gibbes, 1850)   , a species with a wide distribution in the Mediterranean, east and west Atlantic, and east Pacific. Holthuis & Gottlieb (1958) were the first to point out the existence of P. laevimanus   from specimens collected near Sydney in 1955. Davie (2002) correctly listed P. laevimanus   , giving its distribution as New South Wales, Queensland, and Norfolk I. The specimens collected from Rapa I. greatly extend eastward the distribution of P. laevimanus   . In French Polynesia at least, the species seems to be confined to subtropical latitudes. It is one of the commonest intertidal crabs in Haurei Bay, Rapa I. (28°S) but it has never been observed in the Austral Is., which are situated at more northern latitudes (Raevavae I., 24°S; Tubuai I., 23°S).

Pachygrapsus laevimanus   may also be present much further east on Easter I. at the same latitude as Rapa I. Similarities between the decapods of the two islands have been shown by Poupin (2003). A Pachygrapsus   female collected in 1904 on Easter I. ( USNM 33186) and attributed to P. transversus   by Rathbun (1907) shows that although very similar to P. transversus   of the same size and sex from the Atlantic, it differs slightly in the setation of the ambulatory legs. Females of P. transversus   from the Atlantic have a slight brush of setae on the P2 propodus and no setae on the P3 propodus, whereas on the Easter I. female there is no brush on P2 and a faint one on P3, a characteristic of P. laevimanus   . Unfortunately, no male specimen of P. transversus   was available from Easter I. to confirm this identification. Garth (1973) confirmed the presence of P. transversus   on Easter I. but did not mention the shape of the G1 and did not compare his specimens with P. laevi­ manus. Garth’s Easter I. specimens have not been located in several collections ( CAS, LCMN, SIO, USNM). Other specimens from Easter I. attributed to P. transversus   by Báez & Ruiz (1985), and deposited in the MNHNS collections, were not available for this study. While the morphology of the G1 should confirm the identification, it seems most likely that P. laevimanus   , not P. transversus   , is found in Easter I.

AM

Australian Museum

MNHN

Museum National d'Histoire Naturelle

QM

Queensland Museum

USNM

Smithsonian Institution, National Museum of Natural History

CAS

California Academy of Sciences

SIO

Scripps Institution of Oceanography

Kingdom

Animalia

Phylum

Arthropoda

Class

Malacostraca

Order

Decapoda

Family

Grapsidae

Genus

Pachygrapsus

Loc

Pachygrapsus laevimanus Stimpson, 1858

Poupin, Joseph, Davie, Peter J. F. & Cexus, Jean-Christophe 2005
2005
Loc

Pachygrapsus transversus

Baez, P. & Ruiz, R. 1985: 105
Garth, J. S. 1973: 324
Rathbun, M. J. 1907: 29
1907
Loc

Pachygrapsus laevimanus

Poore, G. C. B. 2004: 508
Davie, P. J. F. 1998: 151
Holthuis, L. B. & Gottlieb, E. 1958: 102
Stimpson, W. 1907: 117
Stimpson, W. 1858: 48
1858