Zoology Publications from Victoria University of Wellington—Nos. 78, 79 and 80

Alpheid larval characters

Alpheid larval characters

1. Supraorbital spines when present without spinules (Fig. 1A).
2. Pereiopod 5 develops before pereiopods 3 and 4, terminal spine of dactylus extremely long (extends at least beyond eyes) and provided with spinules distally (Figs. IB, C).
3. Protopod of maxilla with 3 endites only, exopod shorter than endopod in early larvae (Fig. 1H).
4. Endopod of maxillule small and unsegmented.
5. Endopod of maxilliped 1 with two or three incomplete segments (as indicated by setation), never with indication of four segments (Figs. ID, E).
6. Maxillipeds 2-3 and pereiopods raptorial in form, with spiniform serrate and simple setae, dactylus produced into a strong spine (e.g. Figs. IF, G).

Key to larvae of the New Zealand Alpheidae 1
A. Rostrum as long as or longer than antennular peduncle; with supraorbital spines from zoea 2; strong posterolateral spines on abdominal somite 5 from zoea 3; pereiopod 5 not developed until zoea 3 (Fig. 1A) Betaeopsis aequimanus
Rostrum short, does not extend beyond eyes; without supraorbital spines or posterolateral abdominal spines in zoeae 1-3; pereiopod 5 developed in zoea 2 (Fig. IB) B
B. Endopod of maxilliped 1 very small, with two incomplete segments (as indicated by setation) (Fig. ID) Alpheus richardsoni
Endopod of maxilliped 1 with three incomplete segments (as indicated by setation) C
C. Ischium of maxilliped 3 without spiniform seta (Fig. IF) Alpheus socialis
Ischium of maxilliped 3 with spiniform seta (Fig. 1G) Alpheopsis garricki