Periclimenaeus nobilii Bruce, 1974

Bruce, A. J., 2006, Pontoniine shrimps (Decapoda: Palaemonidae) from the island of Socotra, with descriptions of new species of Dactylonia Fransen, 2002 and Periclimenoides Bruce, 1990, Zootaxa 1137, pp. 1-36 : 19-20

Periclimenaeus nobilii Bruce, 1974

Figure 1 C–D

Periclimenaeus nobilii Bruce, 1974: 1577 –1581, Figures. 13f, 14.

Material examined: 1ɗ, MAP­070, ST­017, 12°39.398’N 53°24.117’E, Ras Asfar, North of Shuab, N of Shuab, NW­coast, 10–11 m, 9 March 1999, NHCY. (2) 1 ɗ, MAP­070B, ST­017, 12°39.398’N 53°24.117’E, Ras Asfar, N of Shuab, NW coast, 10–11 m, 9 March 1999, NHCY. (3) 1ɗ, 1 ovig. Ψ, MAP­139, ST­068, 12°41.062’N 54°04.508’E, Hawlaf Bay, E of Hadibo, N coast 12–14 m, 19 March 1999, SMF 29207.

Host: (1), dead coral; (2), no data. Presumably from tunicate host (Ascidiacea)..

Regional records: No previous regional records.

General distribution: Type locality: Red Sea, without precise locality. Also reported only from La Réunion: (Bruce, 1983) and New Caledonia ( Bruce, 1991).

Remarks: Specimen (1), CL 2.6 mm, lacks the minor second pereiopod. It has a rostral dentition of 2/0, with rostrum depressed, acute, distally up­curved, with the posterior part strongly carinate and slightly eaved ( Figure 1 C), reaching to middle of intermediate segment of antennular peduncle.

Specimen (2), CL 6.0 mm, has a similar rostrum. It lacks the major second pereiopod and all ambulatory pereiopods, so cannot be identified with certainty. The minor second pereiopod chela is 1.4 times the CL and has the dactylus about 0.36 of the palm length, subequal to the fixed finger length, with a feebly sinuous denticulate cutting edge, bearing about 60 minute denticles, with the teeth on the distal third distinctly larger than the proximal teeth. The cutting edge of the fixed finger is deeply channelled, a character probably overlooked in the original description. The telson corresponds with the description of P. nobilii (see below).

Specimens (3), CLs male 1.9 mm, ovigerous female 2.0 mm, are similar, without second pereiopods and with few ambulatory pereiopods. The male third pereiopod has a particularly long and slender acute basal process on the dactylar corpus ( Figure 1 D).

The form of rostrum in all specimens closely resembles that of the P. nobilii holotype (Bruce, 1974, figure 14d) which has two dorsal teeth, posteriorly strongly carinate, reaching to well beyond the anteroverted cornea, to the distal border of the intermediate antennular peduncular segment, with a convex ventral margin, and in specimen (2), the dactyl of the minor chela also scarcely over­reaches the fixed finger, with a similar dentition.

Figures

FIGURE 1. Conchodytes meleagrinae Peters, F­ 061, ST­ 189 / 190, (A), second pereiopod, fingers. (B), same, cutting edges. Periclimenaeus nobilii Bruce, MAP­ 139, ST­O 68, ovigerous female. (C), anterior carapace and appendages, lateral. Male. (D), third pereiopod, distal propod and dactyl. Periclimenaeus sp., aff. nobilii Bruce, MAP­ 070 A, ST­ 017, female. (E), third pereiopod, propod and dactyl. (F), same, distal propod and dactyl. G, telson.