Pachygrapsus plicatus, (H. MILNE EDWARDS, 1837)

Flores, Augusto A. V., Paula, José & Dray, Tiago, 2003, First zoeal stages of grapsoid crabs (Crustacea: Brachyura) from the East African coast, Zoological Journal of the Linnean Society 137 (3), pp. 355-383 : 368-373

PACHYGRAPSUS PLICATUS (H. MILNE EDWARDS, 1837)

(FIGS 11,12)

Dimensions: TT 0.80 mm ± 0.02, CW 0.37 mm ± 0.02, CL 0.46 mm ± 0.02.

Carapace ( Fig. 11a ): without a distinct postero-dorsal protuberance as found in P. minutus .

Antennule ( Fig. 11b ): with 2 terminal setae.

Antenna ( Figs 11a,c ): protopodal process with 2 rows of spines of increasing size towards the tip.

Maxillule ( Fig. 12f ): coxal endite with 6 (4 sparsely plumose, 1 simple, 1 plumodenticulate) setae; basial endite with 5 (1 subterminal, plumodenticulate; 1 stout, terminal sparsely plumose; 2 stout, terminal plumodenticulate; 1 stout, terminal denticulate) setae.

First maxilliped ( Fig. 12h ): basis with 8 setae (arranged 2 sparsely plumose; 2 sparsely plumose; 2 sparsely plumose; 2 sparsely plumose); endopod 5- segmented with 1 (sparsely plumose), 2 (sparsely plumose), 1 (plumodenticulate), 2 (plumodenticulate), 5 (1 subterminal simple + 4 terminal plumodenticulate) setae.

Second maxilliped ( Fig. 12i ): basis with 4 setae (arranged 1 sparsely plumose, 1 sparsely plumose, 1 sparsely plumose, 1 sparsely plumose); endopod 3-segmented with 0, 1 (denticulate), 5 (1 subterminal simple + 1 subterminal denticulate, 2 terminal sparsely plumose, 1 terminal simple) setae.

Abdomen ( Figs 11a, d ): somite 2 with 1 pair of dorsolateral processes directed anteriorly, somite 3 with 1 pair of dorsolateral processes directed ventrally; lateral processes absent in somite 4; postero-lateral processes in somites 2–5, small in somite 2, and conspicuous, bearing distinct lobes in somites 3–5.

Telson ( Figs 11d,e ): with 2 postero-lateral pairs of spines of similar size; spinules distributed over margins and distal half of forks, except the tips; forks small, divergent.

Figures

Figure 11. Pachygrapsus plicatus (H. Milne Edwards). First zoeal stage: (a) lateral view; (b) antennule; (c) antenna; (d) dorsal view of abdomen; (e) detail of telson. Scale bars as in Figure 1.

Figure 12. Pachygrapsus plicatus (H. Milne Edwards). First zoeal stage: (f) maxillule; (g) maxilla; (h) first maxilliped; (i) second maxilliped. Scale bars as in Figure 2.