Pasithoe, Goodsir (1842), which Sars assumes as the type of the family, is here relegated to Ammothea.[[431]] Colossendeis, Jarszynsky (1870) (Anomorhynchus, Miers (1881), Rhopalorhynchus, Wood-Mason (1873)), remains as the only genus commonly accepted: large, more or less slender short-necked forms; world-wide, principally Arctic, Antarctic, and deep-sea; about twenty-five species.[[432]] The largest species, C. gigas, Hoek, from great depths in the Southern Ocean, has a span of about two feet. The North Atlantic C. proboscidea and Antarctic C. australis are very closely related to one another. Carpenter would retain the genus Rhopalorhynchus for R. kröyeri, W.-M. (Andamans), R. clavipes, Carp. (Torres Straits), and R. tenuissimus, Haswell (Australia), all more or less shallow-water species, excessively attenuated, with the second and third body-segments elongated, the caudal segment excessively reduced, the club-shaped proboscis on a slender stalk, and other common characters. Pipetta weberi, Loman (1904), is a large and remarkable form from the Banda Sea, apparently referable, in spite of certain abnormal features, to this family; the proboscis is extraordinarily long and slender; the palps have eight joints, the ovigerous legs eleven.
Fam. 3. Eurycididae (Ascorhynchidae, Meinert).—Appendage I. more or less reduced; appendage II. 10–jointed (absent in Hannonia); appendage III. 10–jointed, clawed, with more than one tow of serrated teeth; proboscis movably articulated and more or less bent under the body; auxiliary claws absent.
Fig. [283].—Eurycide hispida, Kr.; side view.
Eurycide, Schiödte (1857) (Zetes, Kröyer, 1845): Appendage I. with two-jointed scape, without chelae in adult; one species (E. hispida, (Kr.)), from the North Atlantic and Arctic, and two others from the East Indies, recently described by Loman. Barana arenicola, Dohrn (1881), is nearly allied. Ascorhynchus, G. O. Sars (1876) (Gnamptorhynchus, Böhm, 1879; Scaeorhynchus, Wilson, 1881), very similar to Eurycide, with which, according to Schimkewitsch, it should be merged, includes large, smooth, elongated forms, with long neck and expanded frontal region, and a long proboscis lacking the long scape that supports the proboscis in Eurycide; about twelve species, world-wide, mostly deep-water. Barana castelli, Dohrn, from Naples is akin to the foregoing genera, but seems to deserve generic separation from B. arenicola. Ammothea longicollis, Haswell, from Australia, is, as Schimkewitsch has already remarked, almost certainly a Eurycide, as is also, probably, Parazetes auchenicus, Slater, from Japan.
Hannonia typica, Hoek (1880), from Cape Town, is a remarkable form, lately redescribed by Loman. The chelophores are much reduced, the palps are absent; the ovigerous legs are 10–jointed, and clawed; the terminal joints of the latter bear long straight spines, scattered over their whole surface; the proboscis is borne on a narrow stalk, and sharply deflexed. The eggs form a single flattened mass, as in Pycnogonum. While the lack of palps would set this genus among the Pallenidae, the remarkable proboscis seems to be better evidence of affinity with Ascorhynchus and Eurycide.[[433]]
Nymphopsis, Haswell (1881), is a genus of doubtful affinities, placed here by Schimkewitsch. The first appendage is well-developed and chelate; the palps are 9–jointed, the ovigerous legs are 7–jointed, none of the joints being provided with the compound spines seen in Nymphon and Pallene. It is perhaps an immature form. Schimkewitsch has described another species, N. korotnevi, and Loman a third, N. muscosus, both from the East Indies.
Fam. 4. Ammotheidae.—Akin to Eurycididae in having the proboscis more or less movably jointed to the cephalic segment, and appendage I. reduced, non-chelate in the adult; the body is compact and more or less imperfectly segmented; appendage II. 4–9–jointed; appendage III. clawless, and the number of joints sometimes diminished, with a sparse row of serrated spines; auxiliary claws usually present.
Ammothea, Leach (1815) (including Achelia, Hodge (1864) = the old non-chelate individuals): appendage I. very small, 2–jointed; appendage II. 8–9–jointed; caudal segment fused with last body-segment; about eighteen species, four from the South Seas, two or three from the East Indies, the rest mostly Mediterranean and North Atlantic, in need of revision. Ammothea longipes, Hodge, is the young of Achelia hispida, Hodge; and Ammothea magnirostris, Dohrn, is apparently the same species. A. fibulifera, Dohrn, seems identical with Achelia echinata, Hodge (of which A. brevipes, Hodge, is the young), and so probably is A. achelioides, Wilson; Endeis didactyla, Philippi (1843), is very probably the same species. A. uniunguiculata, Dohrn (? Pariboea spinipalpis, Philippi (1843)), has no auxiliary claws. Leionymphon, Möbius (1902), contains nine Antarctic forms, allied to Ammothea (including A. grandis, Pfeffer, and Colossendeis gibbosa, Möb., which two are probably identical), with characteristic transverse ridges on the body, a large proboscis, a 9–jointed palp, and somewhat peculiar ovigerous legs. Cilunculus, Fragilia, and Scipiolus are new genera more or less allied to Leionymphon, described by Loman (1908) from the Siboga Expedition.[[434]] Tanystylum, Miers (1879) (including Clotenia, Dohrn (1881), and Discoarachne, Hoek (1880)), has appendage I. reduced to a single joint or a small tubercle, and appendage II. 4–6–jointed; world-wide; about eight species. Austrodecus glacialis and Austroraptus polaris are two allied Antarctic species, described by Hodgson (1907), the former a curious little form with a pointed, weevil-like proboscis, no chelophores, and 6–jointed palp. Trygaeus communis, Dohrn (1881), from Naples, has a 7–jointed, and Oorhynchus aucklandiae, Hoek (1881), a 9–jointed palp; the former has only seven joints in the ovigerous leg. Lecythorhynchus armatus, Böhm (1879), with rudimentary 2–jointed chelophores, and L. (Corniger) hilgendorfi, Böhm, with small tubercles in their place, both from Japan, have also 9–jointed palps: the former, at least, is apparently an Ammothea. Several insufficiently described genera, Phanodemus, Costa (1836), Platychelus, Costa (1861), Oiceobathes, Hesse (1867), and Böhmia, Hoek (1880), seem to be referable to this group; all have chelate mandibles, and may possibly be based on immature forms.
Goodsir’s Pasithoe vesiculosa[[435]] is, in my opinion, undoubtedly Ammothea hispida, Hodge, and so also, I believe, is his Pephredo hirsuta; P. umbonata, Gould[[436]] (Long Island Sound), is, with as little doubt, Tanystylum orbiculare, Wilson.