Fig. [286].—Phoxichilidium femoratum, Rathke, Britain. A, The animal with its legs removed; B, leg and chela.
Fam. 8. Phoxichilidiidae.—Appendage I. well-developed; II. absent; III. present only in the male, having a few simple spines in a single row. The last character is conveniently diagnostic, but nevertheless the Phoxichilidiidae come very near to the Pallenidae, with which, according to Schimkewitsch and others, they should be merged; the two families resemble one another in the single row of spines on the ovigerous legs and in the extension of the cephalic segment over the base of the proboscis.
Phoxichilidium, M.-E. (1840): appendage III. 5–jointed; five or six species (Mediterranean, North Atlantic, Arctic, Australia, Japan). Anoplodactylus, Wilson (1878): appendage III. 6–jointed; auxiliary claws absent or very rudimentary; about twelve species, cosmopolitan, of which many were first referred to Phoxichilidium. A. neglectus, Hoek, comes from 1600 fathoms off the Crozets. Oomerus stigmatophorus, Hesse (1874), from Brest, seems to belong to one or other genus, but is unrecognisable. Anaphia, Say (1821), is in all probability identical with Anoplodactylus, and if so the name should have priority. Halosoma, Cole (1904), is an allied genus from California.
Fig. [287].—Anoplodactylus petiolatus, Kr., Britain. A, Dorsal view; B, side view.
Fam. 9. Phoxichilidae.[[439]]—Appendage I. and II. absent; appendage III. present only in the males, 7–jointed, with minute scattered spines; auxiliary claws well-developed; body and legs slender. The only genus is Phoxichilus (auctt., non Latreille, Chilophoxus, Stebbing, 1902); the type is P. spinosus, Mont. (non Quatrefages), from the N. Atlantic, and P. vulgaris, Dohrn, P. charybdaeus, Dohrn, and P. laevis, Grube, are all very similar. Endeis gracilis, Philippi (1843), is probably identical with P. spinosus, or one of its close allies. There are also known P. meridionalis, Böhm, P. mollis, Carp., and P. procerus, Loman, from the East Indies; P. australis, Hodgson, from the Antarctic; P. böhmii, Schimk., of unknown locality; and forms ascribed to P. charybdaeus by Haswell and by Schimkewitsch from Australia and Brazil.
Fam. 10. Pycnogonidae.—Appendages I. and II. absent; appendage III. present only in the male, 9–jointed, with small, simple spines; auxiliary claws absent or rudimentary; body and legs short, thick-set.
The only genus is Pycnogonum, Brünnich (1764) (Polygonopus, Pallas, 1766); the type is P. littorale, Ström, of the N. Atlantic (0–430 fathoms), to which species have also been ascribed forms from various remote localities, e.g. Japan, Chile, and Kerguelen. P. crassirostre, G. O. Sars, a northern and more or less deep-sea form, is distinct, and so also are P. nodulosum and P. pusillum, Dohrn, from Naples. P. stearnsi, Ives, from California, is like P. littorale, except for the rostrum, which resembles that of P. crassirostre. P. magellanicum, Hoek, P. magnirostre, Möbius, both from the Southern Ocean; P. microps, Loman, from Natal, and four others described by Loman from the East Indies, are the other authenticated species. Of P. philippinense, Semper, I know only the bare record; and P. australe, Grube, is described only from a larval form with three pairs of legs. P. orientale, Dana (first described as Astridium, n.g.), is also described from an immature specimen, and more resembles a Phoxichilus.