Latreillia pennifera Alcock 1900

Latreillia pennifera Alcock, 1900

(Figs 10; 11)

Latreillia pennifera Alcock, 1900a: 118. — Alcock 1901: 71, pl. 7, fig. 27, 27a, 27b. — Kensley 1981: 37. — Williams 1982: 244, figs 3e, 6b, c, 7b, c, 8 (synonymy and references). — Guinot 1991: fig. 11.

TYPE MATERIAL. — No holotype designated; deposit of type material unknown (probably Zoological Survey of India, Calcutta).

TYPE LOCALITY. — Myanmar (= Burma), Andaman Sea, Gulf of Martaban, 14°26’S, 96°23’E, 122 m.

MATERIAL EXAMINED. — Somalia. Anton Brunn, stn 444, 09°36’N- 09°40’N, 51°01’E- 51°03’E, 16.XII. 1964, 80 m, 1 ♂ (USNM 172333). — Stn 445, 09°41’N, 51°03’E, 16.XII.1964, 1 ♂ (USNM 172331).

Seychelles. Percy Sladen Trust Expedition, stn F 8, 62 m, 20.X.1905, 1 ♂ (USNM 41049). — Stn F 3, 71 m, 20.X.1905, 1 ovig. ♀ (USNM 41050).

? Mozambique. Anton Brunn, stn 372-L, 25°07’N, 34°34’E, 112 m, 19.VIII.1964, 1 juv. ♂ (MNHN 172332).

South Africa. Dry specimens from mixed lot examined by Williams (1982), mostly collected in South Africa and Mozambique, 4 ovig. ♀♀ (SAM-A1352, 1453, 6792, 8214).

Madagascar. Mitsio I., 60 m, A. Crosnier coll., II.1960, 1 ♂, 1 ♀ (MNHN-B 28472). — Fort- Dauphin (= Tôlañaro), 90 m, A. Crosnier coll., 25.X.1958, 1 ♂, 1 ♀ (MNHN-B 28473).

Thailand. Andaman Sea, Te Vega, stn 80, off Similan Is., 08°46’S, 97°46’E, 122-127 m, 4.XI.1963, 1 ♂, 1 ♀ (USNM).

Philippine Islands. South China Sea, MUSORSTOM 3, stn CP 121, 12°08’N, 121°18’E, 74-84 m, 3.VI.1985, 1 ♂, 2 ovig. ♀♀ (MNHN-B 28110).

Indonesia. Strait of Makassar, CORINDON, stn CH 206, 01°06’S, 117°45’E, 85 m, 30.X.1980, 1 ♂ (MNHN-B 28111).

New Caledonia. LAGON, stn 696, 21°28.9’S, 166°11.9’E, 57- 41 m, 10.VIII.1986, 1 ♀ (MNHN-B 28112). — Stn 933, 20°44.9’S, 164°14.9’E, 90- 100 m, 27.IV.1988, 1 ♂ (MNHN-B 28113).

Kandjar dredgings, 22°40’ - 22°50’S, 167°10’ - 167°30’E, 200-350 m, P. Tirard coll., 7-10.X.1986, 1 ovig. ♀ (MNHN-B 28183).

SMIB 5, stn DW 88, 22°18.6’N, 168°40.2’E, 350 m, 13.IX.1989, 1 ♂ (MNHN-B 28114).

Passe de Koumac, 20°40.70’S, 164°14.70’E, 65-70 m, 24.X.1993, 1 ♂ (MNHN-B 28115).

BATHUS 3, stn CP 847, 23°03’S, 166°58’E, 405- 411 m, 1.XII.1993, 2 ♂♂, 1 unknown sex (MNHN- B 28318).

DISTRIBUTION. — Indian Ocean (South Africa to the Andaman Sea) and the western Pacific Ocean (Philippine Islands to New Caledonia) (Fig. 11). Depth: 37-411 m.

DIAGNOSIS. — Dorsal surface of gastric region of carapace lacking spine (Fig. 10). Gastric region slender, length 0.35-0.45 of carapace length. Supraocular spines slightly shorter or nearly equal than ocular peduncles. Hepatic swellings not topped by tubercle or spine. Merus of each third maxilliped without tubercle or spine on ventral surface. Abdomen of adult males with all somites distinct; middorsal protuberance on somite 1, acute spine on somite 2. Abdomen of adult females with middorsal protuberance on somite 1, acute spine on each somite 2, 3 (Fig. 10); somites 4-6 broad and fused with proximal spines laterally near articulation with somite 3. Propodus of each last pair of walking appendage (P5) equal or longer than carpus; dactylus of P5 trailing, not forming subchela; distal portion of propodus without spinules (see Williams 1982: fig. 7b, c).

Colour: Carapace “reddish with longitudinal stripes of dark red, the ocular peduncles, chelipeds and legs are closely cross-banded with red, and the retina of the eyes is purplish black” (Alcock 1901: 72).

REMARKS

Latreillia pennifera is close to L. metanesa in its general morphology but easily distinguished by its last pair of pereopods (P5), each having a non-toothed, slender, and trailing dactylus that does not form a subchela (see Williams 1982: fig. 7b, c). In contrast, L. metanesa has a toothed dactylus that forms a subchela against a spined propodus (Fig. 6). Specimens of L. pennifera that lack the P5 are best separated by the absence of a tubercle, tooth, or acute spine on the meri of the third maxillipeds. In L. metanesa there is a tubercle (which varies from a slightly raised area to a high, obtuse tubercle) on the meri.

Castro P. et al.

Other characters that are not always reliable are supraocular spines shorter than the ocular peduncles, absence of a dorsal spine in juveniles and small adults, and a spine or small tubercle on each hepatic swelling. The structure of the male first pleopods is not a reliable character. Although shown as short and with straight borders by Williams (1982: fig. 3e), it can be identical to that of L. metanesa: more slender and slightly curved (Williams 1982: fig. 3d), or long and curved (Williams 1982: fig. 3c, as “near L. manningi ”). No juvenile specimens of L. pennifera were identified during this investigation so it can be speculated that, if a dorsal spine is present, juveniles may be undistinguishable from those of L. metanesa.

L. pennifera has been recorded from slightly shallower depths (37-411 m) than in the other Indowest Pacific species of Latreillia with which it may occur sympatrically: L. metanesa (60-650 m) and L. valida (30-731 m).

Size

Maximum size: ♂ cl 10.4 mm, ♀ cl 12.3 mm (Williams 1982).