Hispidolambrus mironovi (Zarenkov, 1990)

Mclay, Colin L., 2009, Revision of the crab genus Garthambrus Ng, 1996, with the description of two new genera and discussion of the status of Tutankhamen Rathbun, 1925 (Crustacea: Brachyura: Parthenopidae), Zootaxa 2122, pp. 1-50 : 33-35

Hispidolambrus mironovi (Zarenkov, 1990) nov. comb.

( Figs 16 , 17 )

Asterolambrus mironovi Zarenkov, 1990: 233 , fig. 11.

Parthenope (Platylambrus) mironovi — Garth 1993: 792, fig. 6. – Parin et al. 1997: 163 (list). Parthenope mironovi — Parin et al. 1997: 217.

Garthambrus mironovi — Ng 1996: 156, 158. – Ng & Tan 1999: 122 (key).

Type material. SYNTYPES: 1 ovig. female (CL 32.0 mm), Bolshaya Seamount, stn 1921; 1 male (CL 20.2 mm), 1 female (CL 19.4 mm), Bolshaya Seamount, stn 1924; 1 male (CL 17.2 mm), Kupol Seamount, stn 1992; 1 female (CL 26.5 mm), Ichthyologists Seamount, stn 1996; 1 male (CL 21.8 mm), Kupol Seamount, stn 2038; 1 male (CL 30.0 mm), Kupol Seamount, stn 2029. The precise localities were not given in the original description. Garth (1993) examined a male specimen from station 1992 and designated it as a paratype. He noted that this specimen is from the Ichythologists Seamount, but the locality of station 1992 should be from the Kupol Seamount (Zarenkov, 1990: 233). Garth (1993) also gave the carapace measurement of the male specimens (32.0 x 22.3 mm), but the carapace length is different from that given by Zarenkov (1990) which is CL= 17.2 mm. The discrepancy could be due to whether the long spine-like teeth on the posterior margins in the carapace length were added to the measurements taken by Garth (1993).

Material examined. Shoal Guyot: Scripps Institute of Oceanography Downward Expedition, Station HD–73, 25°44’S, 85°25’W, 228 m, rock dredge, 26 Jan 1958: 1 male 42.5 x 26.8 mm (damaged) ( LACM CR 19582671; ex. AHF 5821).

Diagnosis. Dorsal surface of carapace tuberculate, tubercles stellate, without deep lacunae; supra-orbital region spinose. Protogastric, mesogastric, epibranchial, mesobranchial and cardiac regions with large spines, tubercle or spines not fusing together to form smooth ridges or plates. Frontal projection short, less than one quarter carapace length. Epibranchial marginal teeth sharp. Anterior epibranchial margin divided into two sections: anterior section arcuate posterior section straight. Mesobranchial margin without a raised smooth triangular patch. Sub-orbital spine produced, spine tip extending beyond anterior outer corner of antennal article 2. Sub-branchial region densely tuberculate, tubercles paxilliform, stellate. Cheliped merus, carpus outer margins spinose. Upper margin of P5 merus, carpus, propodus spinose; posterior surface spinose.

Distribution. Known only from the type locality, Nazca and Sala y Gómez submarine ridges, Eastern Pacific. Specimens of this species had been collected from between 162 to 800 m (Zarenkov, 1990; Garth, 1992).

Remarks. The crushed and dried specimen from the Los Angeles County Museum that was examined was collected almost at the same place where the type material was taken.

Hispidolambrus mironovi has distinctively spiny carapace and ambulatory legs. It also has a CW/CL ratio 1.5–1.6, similar to Garthambrus stellatus . Garthambrus stellatus can be distinguished from H. mironovi by not having spines on the carapace and chelipeds, while granules on the carapace are stellate. There is also no distinct notch on the anterior epibranchial margin on G. stellatus , which is present in H. mironovi and divides this margin into two sections. We have not been able to examine the gonopods of this species, but there are two illustrations of these in Zarenkov (1990, his Fig. 11 ) and Garth (1993, his Fig. 6 f) and since there are some minor differences we reproduce both here as Fig. 16 .

Hispidolambrus mironovi probably grow to a reasonably large size: Garth (1993) reported a male 42.5 x 26.8 mm from the Guyot Shoal, near San Félix I. ( Chile) on the Juan Fernandez Ridge. Zarenkov (1990) recorded an ovigerous female CL = 32.0 mm (using the CW/CL ratio of other specimens, 1.5, that would estimate the CW as being around 48 mm) from the Bolshaya Seamount. Of all the species dealt with herein H. mironovi is found closest to continental South America. Its distribution ranges from Sala y Gomez to San Félix I., both island groups being part of Chile.

Figures

FIGURE 6. Gonopods. Garthambrus darthvaderi sp. nov.: A, B, holotype, male 19.9 x 14.0 mm (MNHN), New Caledonia, BIOCAL, stn DW 44, 22 ° 47 ’ S, 167 ° 14 ’ E, 440 – 450 m, 30 Aug 1985. — Garthambrus lacunosus (Rathbun, 1906): C, D, holotype, male 30.9 x 21.8 mm (USNM 29842), Hawaiian Is, west coast of Hawaii, Kawaihae. — Garthambrus posidon Ng, 1996: E, F, male 35.3 x 23.8 mm (MNHN), Madagascar; A, C, left G 1; B, D, left G 2; E, right G 1; F, right G 2. Scale bar = 1 mm.

FIGURE 11. Garthambrus darthvaderi sp. nov.: holotype, male 19.9 x 14.0 mm (MNHN), New Caledonia, BIOCAL, stn DW 44, 22 ° 47 ’ S, 167 ° 14 ’ E, 440 – 450 m, 30 Aug. 1985. A, dorsal view; B, front view; C, side view.

FIGURE 16. Gonopods. Hispidolambrus mironovi (Zarenkov, 1990) nov. comb: A, B, male 42.5 x 26.8 mm (LACM CR 19582671; ex. AHF 5821), Shoal Guyot, Eastern Pacific (after Garth 1992: fig. 6 f) (scale bar = 1 mm); C, D, male CL = 30 mm, Kupol Seamount, RV Professor Shtockman, stn 2029, 9 May 1987 (no scale bar available) (after Zarenkov, 1990: fig. 11). A, C, right G 1; B, D, right G 2.

FIGURE 17. Hispidolambrus mironovi (Zarenkov, 1990): male 42.5 x 26.8 mm (LACM CR 19582671; ex. AHF 5821), Shoal Guyot, Eastern Pacific (after Garth 1992: fig. 6 a) (scale bar = 10 mm).