Larval morphology of some New Zealand shallow water shrimps (Crustacea, Decapoda, Caridea) of the families Crangonidae, Hippolytidae and Palaemonidae

Abstract

Larvae of 12 species of New Zealand shallow water Caridea representing the families Crangonidae, Hippolytidae, and Palaemonidae, are described in detail: Pontophilus australis (Thomson)(zoeae 1-5, postlarva 1), Pontophilus chiltoni Kemp (zoeae 1-5, postlarva 1), Pontophilus hamiltoni Yaldwyn (zoea 1), Pontophilus pilosoides Stephensen (zoea 1)(family Crangonidae); Alope spinifrons (H. Milne-Edwards) (zoea 1, with notes on later larvae), Hippolyte bifidirostris (Miers) (zoeae 1-8, postlarva 1), Hippolyte multicolorata Yaldwyn (zoeae 1-8), Nauticaris marionis Bate (zoea 1), Tozeuma novaezealandiae Borradaile (zoea 1) (family Hippolytidae); Palaemon (Palaemon) affinis H. Milne-Edwards (zoeae 1-10, postlarva 1), Periclimenes (Harpilius) yaldwyni Holthuis (zoea 1, with notes on later larvae), Periclimenes (Periclimenes) sp. (zoea 1, with notes on later larvae) (family Palaemonidae). Additional information is given concerning the life history of each species,including notes on fecundity, egg size, and breeding period. Larvae of each species are compared with those of the same genera and families described in the literature, and affinities are discussed in relation to the classification of the adults. Characters common to larvae of the families Crangonidae, Hippolytidae, and Palaemonidae, and to larvae of the genera Hippolyte, Tozeuma, and Palaemon, are defined in the light of current knowledge. Larvae of Palaemon affinis collected from the plankton were compared with those reared concurrently in the laboratory. In zoeae 2-5, planktonic larvae were generally larger than laboratory reared larvae, and in zoeae 3-5 were more developed. Planktonic larvae later than zoea 5 did not fall into discrete larval forms. Those of similar size and with similarly developed pleopods as laboratory reared larvae generally had much lower setal counts. These differences are discussed in relation to the identification of larvae of other species from the plankton. A guide to the identification of New Zealand shallow water Caridea is provided.