LATREILLIIDAE STIMPSON, 1858

Castro, Peter, Williams, Austin B. & Cooper, Lara L., 2003, Revision of the family Latreilliidae Stimpson, 1858 (Crustacea, Decapoda, Brachyura), Zoosystema 25 (4), pp. 601-634 : 604-605

KEY TO GENERA AND SPECIES OF LATREILLIIDAE STIMPSON, 1858

1. Last pair of pereopods (P5) smooth, without conspicuous setae on propodus ( Fig. 2 ); propodus of P5 half or less than half total length of carpus .................. Eplumula (2)

— Last pair of pereopods (P5) with conspicuous setae along full length of propodus, giving it feather-like appearance ( Fig. 1 ); propodus of P5 clearly more than half total length of carpus .................................................................................... Latreillia (3)

2. Absence of spine on each branchial region of carapace of adults. Dorsal surface of gastric region of carapace (“neck”) without a spine except in large females; ventral surface of meri of third maxillipeds without a spine or tubercle ( Fig. 3A ) except some large females; Australia, New Caledonia, and New Zealand................ E. australiensis

— Acute spine on each branchial region of carapace of adult females. Dorsal surface of gastric region of carapace (“neck”) always with a spine; ventral surface of meri of third maxillipeds with an acute spine, particularly in females; acute spine on each branchial region of adult females; Japan to the Philippine Islands...... E. phalangium

3. Dactyli of last pair of pereopods (P5) trail, not forming subchelae ( Figs 10 ; 12 ) .... 4

— Dactyli of last pair of pereopods (P5) forming subchelae by closing against distal portion of propodi, which have spinules ( Fig. 6 ) ........................................................ 5

4. Dorsal surface of gastric region of carapace with spine. Gastric region short in relation to rest of body, its length less than 0.35 of carapace length ( Fig. 12 ); Indo-west Pacific region .............................................................................................. L. valida

— Dorsal surface of gastric region of carapace without spine (prominence may be present). Gastric region slender in relation to rest of body, its length more than 0.35 of carapace length ( Fig. 10 ); Indian Ocean and western Pacific .................. L. pennifera

5. Abdominal somites 4-5 of males fused; Atlantic coast of southern South America .... .............................................................................................................. L. williamsi

— Abdominal somites 4-5 of males distinct, not fused................................................ 6

6. Dorsal surface of gastric region of carapace with well defined spine in juveniles and many small adults; Indo-west Pacific and eastern Pacific regions ............ L. metanesa

— Dorsal surface of gastric region of carapace without well defined spine, rarely in juveniles and small adults, although prominence may be present; Mediterranean Sea and eastern and western Atlantic Ocean............................................................ L. elegans

Figures

FIG. 2. — Eplumula australiensis (Henderson,1888), New Caledonia, station data unrecorded, ♀, dorsal view,right pereopods omitted.

FIG. 1. — Terminology used to describe the carapace and pereopods in members of the family Latreilliidae.

FIG. 3. — Scanning electron micrographs of right third maxillipeds; A, Eplumula australiensis (Henderson, 1888), station data unrecorded; B, Latreillia elegans Roux, 1830, Massachusetts, station data unrecorded; C, Latreillia metanesa Williams, 1982, New Caledonia, CHALCAL 2, stn DW 83, 200 m, juv. ♀ 7.5 × 4.4 mm (MNHN-B 28131); D, Latreillia valida de Haan, 1839, Philippine Islands, station data unrecorded.

FIG. 10. — Latreillia pennifera Alcock, 1900, New Caledonia, station data unrecorded, ♀, dorsal view, left pereopods omitted.

FIG. 12. — Latreillia valida de Haan, 1839, New Caledonia, Vauban trawlings, stn 04, 400 m, ♂ 10.4 × 6.2 mm (MNHN-B 28072), dor-

FIG. 6. — Latreillia metanesa Williams, 1982, station data unrecorded, ♂, dorsal view, left pereopods omitted.