Salmoneus teres Manning & Chace, 1990

Anker, Arthur, 2007, New species and records of alpheid shrimps, genera Salmoneus Holthuis and Parabetaeus Coutière, from the tropical western Atlantic (Decapoda, Caridea), Zootaxa 1653, pp. 21-39 : 32

Salmoneus teres Manning & Chace, 1990

Fig. 5 , 8 a

Salmoneus teres Manning & Chace, 1990: 20 .

Material examined: 1 non-ovig. specimen (male?), MNHN-Na 13712, Guadeloupe, Grand Cul de Sac, under rock on sand-silt bottom, depth about 2 m, hand net, coll. F. Fasquel, Nov 1999.

Description: See Manning & Chace (1990).

Colour: Whitish, semitransparent, brownish inner organs partly visible through carapace ( Fig. 8 a).

Size: The Guadeloupe specimen has CL 4.4 mm, TL 13.1 mm, CL of the Ascension holotype was 2.8 mm ( Manning & Chace, 1990).

Ecology: The single specimen was found under a rock on the silt-sand bottom, at a depth of about 2 m.

Type locality: Ascension Island.

Distribution: Central Atlantic: Ascension Island ( Manning & Chace, 1990). Western Atlantic: Caribbean Sea: French Antilles: Guadeloupe (present study).

Remarks: The present specimen agrees in most features with the holotype of S. teres from Ascension Island ( Manning & Chace, 1990), except for a few minor differences. According to Manning & Chace (1990), the rostrum is “without indication of median rostral carina”, while in the present specimen there is a very slight carina extending to the level of corneas ( Fig. 5 a). The lateral margins of the rostrum are somewhat more convex in the holotype (cf. Manning & Chace, 1990: fig. 10b) compared to those of the Guadeloupe specimen ( Fig. 5 a). The carapace of the Guadeloupe specimen is distinctly pitted ( Fig. 5 a), however, these pits are also present in the type (R. Lemaitre, pers. comm.), although they were not illustrated and their presence was not mentioned by Manning & Chace (1990).

The finding of S. teres in Guadeloupe eliminates this species from the list of endemic decapods of Ascension Island ( Manning & Chace, 1990), and represents a considerable range extension of S. teres from the central Atlantic ( Ascension) to the western Atlantic (eastern Caribbean). Manning & Chace (1990) analyzed the faunal composition of the Ascension decapods and found that of 74 species known from this isolated central Atlantic island, 41 species (55 %) also occur in the western Atlantic. Therefore, more taxa that are currently believed to be endemic to Ascension may eventually be found in the western Atlantic (see also under S. setosus ).

Figures

FIGURE 5. Salmoneus teres Manning & Chace, 1990: non-ovigerous specimen (male?) from Guadeloupe, French Antilles (MNHN-Na 13712): a—frontal region, dorsal view; b—same, lateral view; c—major cheliped, lateral view; dsame, chela, mesial view; e—same, ischium to carpus, mesial view; f—minor cheliped, lateral view; g—second pereiopod, lateral view; h—third pereiopod, lateral view; i—posterior abdominal somites and tail fan, lateral view; j—preanal plate of sixth abdominal somite, ventral view; k—telson, dorsal view. Scale bar = 1 mm.

FIGURE 8. Habitus and colour patterns: a— Salmoneus teres Manning & Chace, 1990, non-ovigerous specimen (male?) from Guadeloupe (MNHN-Na 13712) (photograph by Frédéric Fasquel); b – d— Parabetaeus hummelincki (Schmitt, 1936): b—young female from Bayahibe, Dominican Republic (MNHN-Na 16391); c—ovigerous female from Bermuda (specimen in BAMZ [not examined], photograph by Wolfgang Sterrer); d—ovigerous female from St. Vincent, photographed in situ at a depth of about 8 m; specimen not collected (photograph by Andrew J. Martinez).