Stilwell—Oldest volutes from early Paleogene
excellent preservation of both volutes suggests minimal transport. The holotype ofW. henaconstricta reveals an oblique repaired break quite similar to other ‘Wangaloan’ gastropods on its antepenultimate whorl that seemingly little affected its sculpture on later teleoconch whorls. The break was probably caused by a lip-peeler such as a decapod that either used the gastropod as a meal and/or abode.
Etymology.—Species named from the Greek henos (= old) and Latin constrictus (drawn together, contracted) for its early occurrence in the New Zealand Paleocene and for its adapical constriction.
Wangaluta? neozelanica (Finlay and Marwick, 1937) Figure 6I, 6J
1937 Paleopsephaea neozelanica Finlay and Marwick, p. 80, pl. 11, figs. 6–7.
1966 Paleopsephaea neozelanica Finlay and Marwick; Fleming, p. 328, pl. 115, figs. 1409, 1411;
1990 Paleophsephaea (err. pro. Paleopsephaea) neozelanica Finlay and Marwick; Beu and Maxwell, pp. 88, 205, 414.
2003 Paleopsephaea neozelanica Finlay and Marwick; Snyder, p. 239 (error, not a Cretaceous species).
Supplementary description.—Shell medium-sized, moderately robust to robust, fusiform; spire unknown except for small fragment, probably about the same height as aperture, see- mingly concave adapically and convex abapically reflected strong axial ribs; penultimate whorl slightly constricted centrally; suture apparently abutting, wrapped around axial ornament of succeeding whorl; growth lines suborthocline; last whorl elongate, rather narrow, constricted abapically and drawn out to a moderately long neck with out a fasciole; last whorl with gentle subsutural adapical constriction and subsutural swelling; ornamentation of approximately 15 pro- nounced rounded axially extending ribs, slightly narrower than the interspaces and becoming obsolete on last half of last whorl; axials extend from suture below to medial position marked by slight constriction on penultimate whorl and fade on last whorl at onset of basal constriction; no spiral sculpture; aperture long, narrow, not notched abapically, siphonostomatous; inner lip with moderately thick broad callus; columella long, straight bearing a single strong oblique plait centrally and an extremely poorly developed obsolete one slightly above; outer lip moderately thick.
Dimensions.—Holotype TM 7343 (GNS) height 44.0mm incomplete, diameter of last whorl 22.0mm.
Type.—Holotype TM 7343 (GNS; Finlay and Marwick, 1937, pl. 11, fig. 6–7; Fleming, 1966, pl. 115, figs. 1409, 1411).
Figured specimen.—TM 7343 (GNS). Material.—Holotype.
37
Locality.—Boulder Hill, Dunedin, Otago, South Island, I44/ f8486 (type).
Stratigraphic range.—Wangaloa Formation (‘Wangaloan’ Stage = lower part of Teurian Stage, Danian, early Paleocene, probably G. golzowense Zone, ca. 64–62 Ma).
Geographic distribution.—Boulder Hill, Otago.
Discussion.—Paleopsephaea Wade, type species P. mutabilis Wade, 1926, from the Late Cretaceous of North America, is characterized by its fusiform outline, whorls with an adapical constriction, abapically constricting last whorl that extends to a moderately long siphonal canal, dominant sculpture of strong collabral transverse ribs, slightly curved siphonal canal (inclined to the left) and usually three oblique plaits on the columella (Sohl, 1964, p. 209). Paleopsephaea is a long ranging and widespread Late Cretaceous genus that is similar to both Dril- luta Wade, 1926, and Bellifusus Stephenson, but ‘differs from the former primarily by its lack of a strong collar and from the latter by its less inflated and rounded whorls, its more subdued ornament, and loess strongly constricted whorls’ (Sohl. 1964, p. 209). Paleopsephaea was placed in Volutidae by Finlay and Marwick (1937, p. 80) and Wenz (1943, p. 80) and later in Fasciolariidae by Sohl (1964, p. 209). Fleming (1966, p. 328) questionably placed P. neozelanica Finlay and Marwick, 1937, in the Volutidae: Athletinae. Beu and Maxwell (1990, pp. 88, 205) regarded the ‘Wangaloan’ species as ‘almost certainly a turbinellid’ and assigned this species to the subfamily Ptycha- tractinae. In a review of the fossil genera of the Ptychatractinae, Harasewych (1987) excluded Paleopsephaea from the sub- family. However, the shell morphology of Paleopsephaea is similar to taxa within the Ptychatractinae; ‘recent work on the higher classification of Volutidae suggests that many of the ‘volutid’ genera and subfamilies that diversified in the Mesozoic may not be related to our modern concept of Volutidae.’ (M.G. Harasewych, personal communication). Most recently, Snyder (2003) retained this species in Paleosephaea, but did so without comment; he apparently consulted Finlay and Marwick (1937), as Snyder stated the species is from the New Zealand Cretaceous, but today the assemblages are dated as Danian (early Paleocene). Paleopsephaea neozelanica is doubtfully regarded herein
(p. 123, pl. 40, figs. 4–5; see also Wenz, 1943, p. 1328, fig. 3772; Sohl, 1964m p. 209–210, pl. 28, figs. 1–6), from the latest Cretaceous of North America differing in having constricted and apparently subtrapezoid whorls, no spiral sculpture and only one strong and a second feeble columellar fold opposed to several in P. mutabilis. These differences are significant and should be considered to be interspecific variation, especially when other species assigned to Paleopse- phaea are compared. The affinity of Paleopsephaea neozelanica most certainly lies with Wangaluta n. gen., although its allocation to Ptychatractinae, as suggested by Beu and Maxwell (1990), is arguable and not necessarily appropriate. Beu and
as a member of this genus as it differs greatly from other described members of the group. Finlay and Marwick (1937, p. 81) remarked that his species seems to be closely allied with the type species of Paleopsephaea, P. mutabilis Wade, 1926
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