Stromboidea

• Aporrhaidae
  • Anchura
    • Anchura wilkinsoni Etheridge jun., 1892

Original Description of Anchura wilkinsoni by Etheridge, 1892, p. 486:

• "Anchura? Wilkinsoni, sp. nov., Pl. 31, figs. 4 and 5. (Compare Alaria or Anchura, sp., Hudleston, Geol. Mag., 1890, vii. (3), p. 242, t. 9, f. 2.) Sp. Char. Shell (without the expanded lip) fusiform, of six or more whorls, angulated in the middle line, the last unequally biangular; last whorl abruptly contracted into the base of the beak below; aperture (?) rhombic oval; the median angular line of all but the last whorl occupied by small, semi-separate nodes; carina of the last whorl without any apparent upward flexure, but below it is a second and finer subparallel keel, which diverges somewhat downwards; general surface covered with revolving striae."

Locus typicus: "Evora Station, twenty-five miles north-east of Blackall (Rowland Morrisby)", Queensland, Australia

Stratum typicum: Cretaceous

• "Obs. The outer lip, with its digitation or digitations, is unknown, and the inner lip not preserved. Through the non-preservation of those portions and the canal, it is difficult to accurately determine the genus to which this shell should be referred. It may be either Aporrhais, Anchura, or Drepanochilus; but from the divergence of the revolving carinae on the last whorl, and thereby probably indicating two digitations of the outer lip, one of the two former is the most likely. In their present condition our specimens are not unlike Dicroloma, Gabb.; but the species may for the present be referred to Anchura provisionally. It is possible that the “ Alaria or Anchura" figured by Mr. Iludleston from South Australia is a different species from A. ? Wilkinsoni. The latter is named in honour of the late Mr. C. S. Wilkinson, Government Geologist of New South Wales."

Anchura wilkinsoni Etheridge, 1892, pl. 31, figs. 4, 5

History and Synonymy

1890

Hudleston, 1890, p. 242 about Alaria or Anchura sp.:

• "Anchura (Conrad) is a sub-genus of Alaria (monodactyl), where the wing presents a securiform bifurcation at the extremity. It seems confined to the Cretaceous, e.g. Anchura carinata, Mantell (Fischer, Man. Conch, p. 676)."
• "Approximate length, without the "tail" 35 mm."
• "Spiral angle 23°."
• "The number of whorls is from ten to twelve; these are full and rounded in the early stages (the extreme apical whorls are unknown), carinated in the later stages; carina nearly median, and ornamented with short thick tuberculations; a second carina is sometimes displayed at the base of the whorls. Body-whorl angular, salient and bicarinated; the posterior carina very strong and prolonged into a stout digitation, the true termination of which is unknown. In some specimens the carinas of the body-whorl are tuberculated, in others apparently not so. The sutures are rather open, so that the base of the whorls are partly uncovered. Other indications wanting. This species occurs in black argillo-calcareous nodules at Primrose Springs. Some of the nodules are full of interior casts, with portions of shell substance adherent, but no casts of the exterior or of the appendages are available at present. Accurate diagnosis and strict comparisons are therefore difficult. No species of Alaria is enumerated in Moore's "Australian Mesozoic Geology"; but Mr. Etheridge, jun., figures Anchura Wilkinsoni (Queensland Pal. pl. 31, figs. 4 and 5), which is shorter, possesses a wider spiral angle, and has more slender costas on the carina of the whorls of the spire than is the case with our species, which I consider to be different. On the other hand, our species presents many points of resemblance to Anchura carinata, Mantell, of the Gault. Indeed, if they are not the same species, they are very closely allied; and as I only have access to a cast of the one and to shells of the other, a true comparison is impossible. If we had any evidence of the securiform termination of the wing in the Australian fossil, I should be almost disposed to pronounce in favour of its identification with Anchura carinata."

Alaria or Anchura sp., Hudleston, 1890, pl. IX, fig. 2

References

• Hudleston, W.H. 1890. Further Notes on some Mollusca from South Australia; The Geological Magazine, new series, decade III, vol VII (6), 241-246, pl. IX, Fulltext
• Jack, R.L. & Etheridge, R. 1892. The Geology and Palaeontology of Queensland and New Guinea, ; James Charles Beal Government Printer, London, vol. 1: I-XXXI, 1-768, Fulltext, vol. 2: Plates and Map, I-IV, pls. 1-68, 1 map, Fulltext