Stromboidea

• Aporrhaidae
  • Anchura
    • Anchura callosa Whiteaves, 1903

Original description of Anchura callosa by Whiteaves, 1903, p. 358:

• Shell fusiform, spire elongated, turreted, slender, outer volution expanded and alate, though the exact shape of the alation is not shown in the only specimen that the writer has seen. Volutions eight or nine, those of the spire rounded, but slightly compressed laterally, the outer one somewhat inflated, but obliquely flattened next to the suture, subangular and lightly shouldered a little behind its midheight or midlength, and narrowing rapidly to the base anteriorly; outer lip expanded and alate, its posterior margin, the only part of the wing that is clearly shown, being broadly and shallowly concave; columella incrusted by large callus, which forms quite a thick rounded projection anteriorly. Surface marked by rather distant, obtuse and not very prominent plications or rib-like folds, which cross all the volutions transversely and are themselves crossed by numerous small acute, spiral ridges, the shoulder of the outer volution being distinctly nodose."

Stratum typicum: Santonian(?) to early middle Campanian, Submortoniceras chicoense Zone, Turritella chicoensis holzana Zone. (Elder & Saul, 1996)

Locus typicus: 2,25 miles up the Nanaimo River, Vancouver Island, British Columbia, Canada (Elder & Saul, 1996)

Types: Holotype GSC 5790 (Bolton, 1965) (Elder & Saul, 1996)

Comment Whiteaves, 1903, p. 359:

• "The foregoing is a description of the imperfect specimen from the Trent River, figured, of the natural size, on Plate 15 of the second part of this volume. This specimen was referred by the writer to the Rostellaria stenoptera of Goldfuss, but this reference seems to be no longer tenable. In the Canadian specimen the whorls can scarcely be described as minutely and spirally striated, the ribs on the last volution are not all strongly granulated, and it is by no means certain that the wing, when entire, was narrow and sword shaped. Moreover it does not seem probable that a fossil from the Nanaimo group of the Vancouver Cretaceous is identical with a species from the Upper Greensand of Westphalia. For these reasons it is now thought desirable to distinguish the specimen from the Nanaimo River by a new specific name. Among the fossils of the California Cretaceous, Anchura transversa of Gabb would seem to come nearest to A. callosa, but the former is represented as being wider than long, and of comparatively diminuitive size i.e., only ten millimetres in length, by thirteen mm. in width."

Anchura stenoptera Goldfuss in Whiteaves, 1879, pl. 15, fig. 11.

History and Synonymy

1879

Whiteaves, 1879, p. 123:

• "Anchura stenoptera, Goldfuss. (Sp.)"
• "Productive Coal Measures, Division A, Nanaimo River, V.I., two miles and a quarter up; J. Richardson, 1872. A single and rather imperfect individual, which appears to be identical with the above named European species. A. stenoptera was originally described from the "chloritic chalk" or Upper Greensand of Westphalia, and, according to Prof. Morris, it has since been found in the Lower Chalk of Sussex. As there are some slight differences between the specimen collected by Mr. Richardson and the shell represented y Goldfuss, it has been thought desirable to give two figures of the former."

Specimens from private collections

Anchura callosa Whiteaves, 1903; Santonian/Early Campanian,Trent River Formation; Northwest Bay, Parksville, British Columbia, Canada; 7.2 cm length; coll. Rick Ross , ex Peter Bock collection

References

• Al-Dulaimi S.I. (2020). Late Campanian-Maastrichtian Gastropoda from Bekhme Formation, Northern Iraq. Iraqi Geological Journal, Vol. 53, No. 1C, 2020
• Elder & Saul, 1996
• Taff, H.A., Hanna, G.D. & Cross, C.M. 1940. Type locality of the Cretaceous Chico Formation. Geological Society of America Bulletin 51: 1311-1328.
• Whiteaves, J.F. 1879. on the fossils of the Cretaceous rocks of Vancouver and adjacent Islands in the strait of Georgia. Canada Geological Survey, Mesozoic Fossils, 1(2): 93-190, Fulltext.
• Whiteaves, J.F. 1903. On some additional fossils from the Vancouver Cretaceous, with a revised list of species therefrom. Canada Geological Survey, Mesozoic Fossils, 1(5): 309-415, Fulltext.