Strobopagurus sibogae (De (De Saint Laurent, 1972)

Lemaitre, R., 1996, Hermit crabs of the family Parapaguridae (Crustacea: Decapoda: Anomura) from Australia: species of Strobopagurus Lemaitre, 1989, Sympagurus Smith, 1883 and two new genera., Records of the Australian Museum 48 (2), pp. 163-221 : 167-169

Strobopagurus sibogae (De Saint Laurent, 1972)

Fig. 1

Parapagurus sibogae De Saint Laurent, 1972: 116 , figs 10, 23 (type locality: Indonesia, Siboga Exp. sta. 12).

Strobopagurus sibogae .- Lemaitre, 1989: 36.

Holotype. Female ovig. (SL 7.4 mm), Indonesia, Siboga Exp. sta. 12, 07°15'S, 115°15.6'E, 289 m, 14 Mar 1899, colI. M. Weber, ZMA Del 03.l09.

Australian material. WESTERN AUSTRALIA: 1 female ovig. (SL 7.5 mm), NW ofAugustus Is. , 13°33.3'S, 122°54.5'E, FRV Soe /a, 396 - 390 m, 14 Feb 1984, WAM 1320-86 . 4 males (SL 4.6-6.0 mm), 3 females (SL 4.0- 4.9 mm), NW of Collier Bay , 14°16'S, 122°38.3'E, FRV Soela , 302 m, 14 Feb 1984, coll. S. Slack-Smith, WAM 1314 -86 . 2 males (SL 4.7, 6.9 mm), NW of Collier Bay , FRV Soe /a, sta. S01/84/074, 14°16.5'S, 122°34.4'E, 302 m, 14 Feb 1984, coil. S. Slack­Smith, WAM 1316-86 . 1 male (SL 5.2 mm), 1 female (SL 5.8 mm), NW of Leveque , FRV Soe /a, 14°49.0'S, 121°36.I'E, 302 - 300 m, coll. S. Slack-Smith, 12 Feb 1986, WAM . 1 male (SL 8.6 mm), NW of Beagle Bay , FRV Soe /a, 15°13.5'S, 121°08.9'E, 352 m, 11 Feb 1984, WAM 1107 -86 . 2 males (SL 7.8, 8.1 mm), 1 female (SL 5.2 mm), NW of Beagle Bay , 15°20'S, 121°09.6'E, FRV Soela , 300-302 m, 11 Nov 1984, colI. S. Slack-Smith, WAM 1133 -86 . 1 female (SL 7.9 mm), WNW of Lacepede Arch , 15°40.2'S, 120037.3'E, FRV Soela , 10 Feb 1984, WAM . 1 male (SL 5.6 mm), W of Lacepede Arch , 16°55.8'S, 119°53.9'E, FRV Soela , 426 m, 19 Feb 1984, WAM 1307 -86 . 1 male (SL 4.5 mm), 1 female (SL 6.2 mm), W of Lacepede Arch , FRV Soela , sta. SOO1/ 84/105, 16°56.9'S, 119°52.0'E., 432 m, 21 Feb 1984 WAM 1297-86 . 1 female (SL 4.8 mm), W of Lacepede Arch , 16°57'S, 119°51'E, FRV Soe /a, 436 m, 22 Feb 1984, WAM 1099 -86 . 1 female (SL 6.7 mm), W of Broome , FRV Soela , sta. 01/841122, 17°59-54'S, 118°23 -29'E, 390 m, 24 Feb 1984, WAM 863 -86 . 1 male (SL 6.0 mm), North West Shelf , FRV Soela , sta. 0184/29, 18°1O.15'S, 118°14.4'E, 302 m, 2 Feb 1984, colI. T . Ward , NTM Cr 007014. 1 female (SL 4.6 mm), Courageous , sta. 5, 18°08'S, 118°13'E, 350-354 m, 17 Aug 1985, WAM 1011-85 . 1 male (SL 5.2 mm), NNE Cape Lambert , 18°32'S, 117°21'E, FRV Soe /a, 496 -504 m, 8 Apr 1982, WAM 1237 -86 . 4 males (SL 5.0- 6.5 mm), 1 female (SL 5.3 mm), FRV Soela , sta. NWS-7, 18°32.2'S, 117"30.9'E, 392 -400 m, 25 Apr 1982, NTM Cr 010916. 2 males (SL 5.8, 6.0 mm), 1 female (SL 5.3 mm), North West Shelf , FRV Soela , CSIRO cruise 0184, sta. 22, 18°34.3'S, 117°30'E, 202 m, 1 Feb 1984, NTM Cr 000669. 1 male (SL 6.5 mm), Scampi , FRV Soela , sta. NWS-6, 18°41.6'S, 117°18.6'E, 320-360 m, 25 Apr 1983, NTM Cr 010915. 3 males (SL 5.3- 6.3 mm), North West Shelf , FRV Soela , sta. 0184/13, 18°55.3'S, 116°09'E, 403 m, 30 Jan 1984, NTM Cr 006858. 1 male (SL 6.0 mm), FRV Soe /a, CSIRO cruise 0184, 19°15'S, 115°38'E, sta. NNS-36 no, 404 m, 29 Jan 1984, colI. T . Ward , NTM Cr 010914. 1 male (SL 5.5 mm), North West Shelf , FRV Soela, cruise 0184, sta. T/8 , 19°20.2'S, 115°44.1'E, 307 m, 29 Jan 1984, NTM Cr 000670. QUEENSLAND: 1 male (SL 5.0 mm), Marian Plateau , FRV Soela , sta.0685-03, 22°34.8'S, 158°38.7'E, 314-319 m, 16 Nov 1985, NTM er 010917. 1 female ovig. (SL 5.8 mm), E of Gold coast, FRV Kapala , sta. K78-09-05, 550 m, 2 Jun 1978, AM P40419 .

NEW SOUTH WALES: 1 female (SL 4.5 mm), E of Long Reef Point, Sydney, FRV Kapala , sta. K78-26-02, 33°43'S, 151°40'E, 143 m, 5 Dec 1978, AM P40418 . 10 males (SL 2.5- 6.1 mm), 6 females (SL 3.3-4.6 mm), 6 females ovig. (SL 4.5- 5.5 mm), off Newcastle, NZOI Tangaroa , cruise U207, 34°11.1'S, 151°26'E, 198 m, 5 Oct 1982, AM P40416 . 3 males (SL 5.8- 7.5 mm), 1 female ovig. (SL 6.9 mm), 20 mi (37 km) off Wollongong , 238- 274 m, 30 Jul 1968, AM P17613 .

Diagnosis. Shield (Fig. la) convex in lateral view. Rostrum broadly rounded, with short longitudinal dorsal ridge. Ocular peduncles more than half length of shield, widening distally. Ocular acicles terminating in strong spine. Antennular peduncles exceeding distal margin of corneae by slightly more than length of ultimate segment. Antennal peduncles exceeding distal margin of corneae by about 0.3 or less length of 5th segment; 2nd segment with dorsolateral distal angle produced, terminating in strong spine (occasionally bifid), mesial margin with small spine at dorsodistal angle. Antennal acicles exceeding distal margin of corneae by as much as 0.3 length of acicle; mesial margin armed with 5 to 7 spines on proximal half. Sternite of 3rd maxilliped with small spine on each side of midline. Right chela ( Fig. 1c ) with dorsal surface unarmed, dactyl with row of spines on mesial margin; palm with mesial and lateral margins well delimited by row of often strong spines (usually double row on mesial margin). Ambulatory legs ( Fig. 1 d-g) with meri shorter on left side than on right; merus of 2nd pereopod 2.5 times as long as dorsoventral height; merus of 3rd twice as long as dorsoventral height. Fourth pereopod (Fig. lh) with propodus elongate, length of dorsal margin subequal to greatest height; propodal rasp with 1 row of rounded scales. Anterior lobe of sternite of 3rd pereopods unarmed, setose. Uropods and telson (Fig. li) strongly asymmetrical; terminal margin of posterior lobes armed with strong, often curved corneous spines.

Distribution. Western Pacific: Indonesia, China Sea, Japan, and Australia. Depth: 40 to 550 m.

Affinities. This species most closely resembles Strobopagurus gracilipes (A. Milne Edwards, 1891) ; however, the two can be separated using several characters. The spines on the mesial margin of the antennal acicles and the lateral and mesial margins of the right chela are much stronger in S. sibogae than in S. graeilipes. The dorsoventral height of the meri of the 2nd and 3rd pereopods are greater in S. sibogae than in S. graeilipes (the merus length/height ratio of the 2nd and 3rd pereopods is 2.0 and 2.5 respectively in the former, and 3.0 and 3.5 respectively in the latter). The propodus of the 4th pereopod is about as high as long in S. sibogae , whereas in S. graeilipes the propodus is distinctly higher than long (1.5 times as high as long, length measured dorsally).

Figures

Fig. 1. Strobopagurus sibogae (De Saint Laurent, 1972). a, shield and cephalic appendages; b, left cheliped; c, right cheliped; d, right 2nd pereopod, lateral; e, merus of same, lateral; f, right 3rd pereopod, lateral; g, merus of same, lateral; h, propodus and dactyl of left 4th pereopod, lateral; i, telson. Scales = 2 mm (a-c), 3 mm (d-g), 0.5 mm (h), and 1 mm (i). (Male [SL 6.0 mm], Western Australia, WAM 1314 -86).