Polycheles typhlops Heller, 1862

Ahyong, Shane T. & Chan, Tin-Yam, 2004, Polychelid Lobsters Of Taiwan (Decapoda: Polychelidae), Raffles Bulletin of Zoology 52 (1), pp. 171-182 : 179-181

Polycheles typhlops Heller, 1862

( Figs. 1 D-F, 4H, 5A, B)

Polycheles typhlops Heller, 1862: 392 , pl. 1 figs. 1-6 [type locality: off Sicily]; Chan & Yu, 1989: 166, pl. 1; 1993: 105.

Pentacheles agassizii A. Milne Edwards, 1880: 65 [type locality: off Grenada].

Polycheles doderleini Riggio, 1885: 103 , pl. 3 figs. 1-5 [type locality: Palermo].

Pentacheles hextii Alcock, 1894: 237 [type locality: Andaman Sea].

Polycheles intermedius Balss, 1914: 599 [type locality: between Iceland and the Hebrides].

Material examined. – Tai-Shi fishing port, I-Lan County, NE Taiwan: 1 ovigerous female (cl. 54.3 mm), 1 female (cl. 53.6 mm), ( NTOU), commercial trawler, 4 Sep.1989; 1 female (cl. 26.5 mm), ( NTOU), commercial trawler, 20 Jul.1990; 1 female (cl. 29.8 mm), ( NTOU), commercial trawler, Dec.1990; 1 male (cl. 24.3 mm), ( NTOU), commercial trawler, 20 Oct.1995; 3 males (cl. 32.2-33.2 mm), 2 ovigerous females (cl. 49.0- 56.3 mm), 3 females (cl. 26.0- 56.6 mm), ( NTOU), commercial trawler, 11 Mar.1997; 1 male (cl. 46.8 mm), ( ZRC 2001.0125 ), coll. P. Ng, 6 Nov.2000. Nangfangao fishing port, I-Lan County , NE Taiwan: 2 males (cl. 20.8-39.7 mm), ( NTOU), commercial trawler, 16 Mar.1985; 3 males (cl. 34.3-38.9 mm), 1 ovigerous female (cl. 59.4 mm), 2 females (cl. 29.3-32.5 mm), ( NTOU), commercial trawler, 22 May.1990; 1 male (cl. 41.3 mm), 1 female (cl. 24.4 mm), ( NTOU), commercial trawler, 19 Jun.1991; 1 ovigerous female (cl. 53.1 mm), 1 female (cl. 34.9 mm), ( NTOU), commercial trawler, 21 May.1992; 1 female (cl. 41.4 mm), ( ZRC 2001.0146 ), commercial trawler, coll. P. Ng, 22 May.1998; 3 males (cl. 34.4-43.6 mm), 3 females (cl. 45.4-49.2- 49.4 mm), ( ZRC 2001.0144 ), commercial trawler, P. Ng et al., 28 May.1997. SW Taiwan: 1 ovigerous female (cl. 49.9 mm), ( NTOU), 22º12.92’N, 120º25.93’E, 316-477 m , TAIWAN 2001 CD137, 23 Nov.2001. Tong-Kang fishing port, Ping-Tong County, SW Taiwan: 2 males (cl. 32.3-35.5 mm), ( NTOU), commercial trawler , 23 Mar.1985; 1 female (cl. 46.3 mm), ( NTOU), commercial trawler , 25 Feb.1995; 1 male (cl. 32.3 mm), ( NTOU), commercial trawler , 14 May.1995; 2 males (cl. 34.5-36.1 mm), 2 females (cl. 36.4-41.8 mm), ( ZRC 2001.0145 ) , coll. P. Ng et al. Pratas (Dong-Sha Islands): 1 male (cl. 43.8 mm), ( NTOU), commercial trawler , Jun.1991. Taiwan , no specific locality: 1 female (cl. 50.4 mm), ( NTOU), 1993. Mediterranean Sea: 2 females (cl. 22.7-26.6 mm), ( NTOU, exchanged from B. S. Galil ), Israel , 25 Jan.1995; 1 male (cl. 20.6 mm), 1 female (cl. 21.4 mm), ( NTOU, exchanged from B. S. Galil ), Israel, 1500 m , 7 Dec.1995; 1 female (cl. 43.4 mm), ( SAM), Genova Gulf, Primavera, Italy, 200-300 m , 1933.

Remarks. – Polycheles typhlops is currently attributed a near worldwide distribution, ranging throughout the Indo-West Pacific and both sides of the Atlantic. Four nominal species are currently included in the synonymy of P. typhlops with three from the Atlantic ( P. agassizii , P. doderleini , P. intermedius ) and one from the Indo-West Pacific ( P. hextii ).

The Taiwanese specimens agree in most respects with the Mediterranean specimen and Galil’s (2000) figure of an Atlantic specimen, but differ chiefly in the ornamentation of the second to fifth abdominal tergites and telson. In the Taiwanese specimens ( Fig. 5A ), the anterior and posterior margins, and lower lateral surfaces of the abdominal tergites 2-5 are strongly tuberculate or denticulate, the pleura are distinctly granulate with distinctly denticulate margins (more pronounced in males) and the submedian carinae of the telson are distinctly granulate. In the distinct abdominal ornamentation, the present specimens agree closely with Alcock’s (1894) P. hextii from the Andaman Sea, which is presently regarded as synonymous with P. typhlops . In contrast to the Taiwanese specimens, the Mediterranean specimens examined here and Galil’s (2000) figured Atlantic specimen have sparsely tuberculate anterior and posterior margins of the second to fifth abdominal tergites, the lower tergal surfaces lack tubercles and the pleura are only sparsely tuberculate ( Fig. 5B ). The submedian carinae of the telson in Atlantic specimens are minutely instead of distinctly tuberculate as in large Taiwanese specimens.

It is noteworthy that eastern and western Australian specimens of P. typhlops in the collections of the Australian Museum agree with the Taiwanese specimens in the strong tergal ornamentation but generally have less denticulate pleural margins. The aforementioned differences between the few Atlantic and Pacific specimens suggests P. typhlops might represent a species complex. If this proves the case, P. hextii will have to be resurrected for at least part of the Pacific material. The present specimens are referred to P. typhlops , however, until types of all nominal synonyms of P. typhlops and more specimens from all regions can be studied to assess the stability or degree of variation in the abdominal granulation.

Distribution. – Widespread throughout the Indo-West Pacific and both sides of the Atlantic; 77-2055 m ( Galil, 2000).

Figures

Fig. 5. Second abdominal tergite and pleuron, right lateral. A, Polycheles typhlops Heller, 1862 (Nangfangao fishing port, ZRC 2001.0144, ovigerous female cl. 49.4 mm). B, Polycheles typhlops Heller, 1862 (Genova Gulf, Mediterranean Sea, SAM, female cl. 43.4 mm). Scale = 5 mm.