Mesolamprops denticulatus Ledoyer, 1983

Corbera, Jordi, 2012, Rare and new cumaceans (Crustacea, Peracarida) from the southern margin of the Cap Ferret Canyon (Bay of Biscay), ZooKeys 235, pp. 73-85 : 74-76

Mesolamprops denticulatus Ledoyer, 1983 Fig. 1C

Mesolamprops denticulata - Ledoyer 1983, pp. 73-74, fig. 4; Ledoyer 1987, p. 68, fig. 5.

Mesolamprops sp. A - Elizalde et al. 1993, p. 250.

Mesolamprops denticulatus - Cartes et al. 2003, p. 749; Shalla and Bishop 2007, p. 1196.

Material examined.

Cap Ferret Canyon, Bay of Biscay, ESSAIS I: stn TS01, 44°33.30'N, 2°08.30'W, 346-347 m, 21/04/89, 2 pread. female. ESSAIS II: stn TS04, 44°34.380'N, 2°10.18'W, 484-485 m, 18/05/89, 1 pread. female. ECOFER I: stn TS05, 44°35.57'N, 2°11.21'W, 522-523 m, 1/07/89, 2 pread. female, 1 pread. male, 1 adult male. J.-C. Sorbe leg.

Remarks.

Mesolamprops denticulatus was described from the Mediterranean Sea by Ledoyer (1983), who identified the main diagnostic characteristics of the adult male (the flagellum of antenna 2 extending only to the end of thorax and two pairs of pleopods). Ledoyer also noted the difficulty of distinguishing the females of this species from those of two nearby species, Hemilamprops normani Bonnier, 1896 and Hemilamprops cristatus (Sars, 1870). Nevertheless, a detailed comparative study of the telson and uropod structures has allowed us to establish the main differences. In Mesolamprops denticulatus the telson has only 3-4 pairs of lateral setae (Fig. 1A); it is shorter than in Hemilamprops , and the terminal setae scarcely reach the distal end of the uropod peduncle; the central terminal seta is longer than the remaining two. Moreover, during the same developmental stage, Mesolamprops denticulatus remains smaller than Hemilamprops normani ,based on measurements takenin preadult females (carapace length: 1.13 vs 1.93 mm).

Distribution.

Mesolamprops denticulatus was for a long time considered an endemic Mediterranean species until Shalla and Bishop (2007) reported the presence of this species in the Faeroe-Shetland Channel. In addition, Elizalde et al. (1993) recorded an undetermined Mesolamprops species from the Bay of Biscay, and recently a study of this same material confirmed that this specimens belongs to Mesolamprops denticulatus (Corbera and Sorbe in prep.). In the Mediterranean Sea, Mesolamprops denticulatus is distributed between depths of 170 and 570 m ( Ledoyer 1983, 1987; Cartes et al. 2003), which is a bathymetric distribution pattern similar to that the observed in the Faeroe-Shetland Channel (259-753 m), as well as in the Bay of Biscay (346-708 m).