Go to National Library of New Zealand Te Puna Mātauranga o Aotearoa
Volume 65, 1936
This text is also available in PDF
(992 KB) Opens in new window
– 23 –

New Eocene Mollusca from New Zealand

[Read before the Auckland Institute, March 21, 1934; received by Editor, April 23, 1931; issued separately, September, 1935.]

Genus Crassatellites Krueger.

Type: Crassatella sinuatus Krueger = Crassatella gibbosula Lamarck.

Crassatellites tripliciter n.sp. (Figs. 1, 1a).

This species is represented by two fragmentary specimens collected from the greensands at Waihao Downs. Shell large, thick and solid, subtrigonal, attenuated behind, beaks very near anterior end. A low, rounded angulation runs from beaks to postero-ventral margin; anterior and posterior dorsal margins rapidly descending, the anterior one cut down, ventrally more rapidly than the posterior margin; antero-dorsal margin quite straight, posterior one broken behind. Lunule well impressed, long, and narrow, that of left valve more distinctly sunken than that of right valve. Concentric sculpture of distinct corrugations towards beaks, but represented by growth-striae over remainder of surface. Margin finely crenulate, much as in C. dennanti Tate from Australia.

Height, 45 mm.; length (estimated), 60 mm.

Locality, greensands, Waihao Downs, South Canterbury (Bortonian).

Type material in writer's collection.

Finlay (Trans N.Z. Inst., vol. 56, p. 256; 1926) has stated that the genotype of Crassatellites has finely corrugated margins like the Australian C. dennanti Tate, which is apparently closely related to the genotype. The present fossil is the first of the New Zealand Crassatelliform shells found to possess a margin that is crenulated. In dentition it is quite akin to dennanti, but the ligament pit of the single specimen which shows the hinge is scarcely visible owing to the decorticated state of that particular part of the hinge and the beak. From C. dennanti it differs considerably in shape, being apparently not so strongly winged posteriorly and having the dorsal margins cut downwards much more rapidly, while the Australian shell has its entire surface ornamented by concentric corrugations. This New Zealand shell seems not unlike C. plumbea Chemnitz, from the Calcaire Grossier of France (Eocene).

Genus Serripecten Marwick.
Type: Pecten hutchinsoni Hutton.

Serripecten tahuiana n.sp. (Fig. 2).

This species is known from a singe perfect right valve. Shell not large, equilateral, moderately inflated. Surface ornamented by about twenty-eight strong scaly radial ribs, the interstices wider

– 24 –

than the ribs and bearing a smaller secondary riblet, also scaly. Posterior ear with four radiate scaly ribs, unequal in strength; anterior ear with two weak radiate ribs, apparently not scaly.

Height, 35 mm.; length, 37 mm.

Locality, greensands, McCullough's Bridge, Waihao (Tahuian).

Type in writer's collection.

This species comes nearest to S. enfieldensis (Marwick), a Waiarekan fossil from Lorne, but has coarser and more scaly ribbing, and has not the flattened ribs, which are not finer on anterior part of disc, as in enfieldensis.

Genus Mauia Marwick.
Type: Galeodes maoriana Suter.

Mauia waihaoensis n.sp. (Fig. 3).

Shell of moderate size, strongly and sharply tuberculate. Spire but slightly turreted, its height nearly two-thirds that of aperture. Periphery of spire-whorls low down; whorls straight below periphery and with a lightly concave shoulder above. The body-whorl contracts rather rapidly below periphery, and is excavated behind posterior ridge of fasciole. Spire-whorls with about ten tubercles on shoulder, weakly prolonged axially for a short distance behind; body-whorl with eight very strong, sharp, rather curved tubercles, slightly directed backwards. Aperture deeply notched in front; outer lip convex, thickened, not reflexed; inner lip distinctly and fairly widely callused; columella-plaits four in number, thin and sharply elevated in young shells, broader and not so sharply elevated in mature shells.

Height, 53 mm.; width, 25 mm. (holotype).

Locality, greensands, Waihao Downs, South Canterbury (Bortonian).

Type in writer's collection.

Waihaoensis can be distinguished from M. angusta (Suter), its nearest relative, by larger size, more attenuate habit (smaller angle of spire and narrower body), more numerous tubercles, and much less gradate spire. Unlike angusta, waihaoensis has axial prolongations of tubercles practically absent from the base of the shell.

Genus Fusinus Rafinesque.
Type (fide Woodring): Murex colus Linné.

Fusinus waihaoica n.sp. (Fig. 4).

This is a puzzling shell, which, in the absence of the protoconch, combines the characters of both Fusinus and Falsicolus. It has the twisted canal and oblique ridge at base of aperture typical of Falsicolus, though some Fusinids have a similar slight twist; but the long slender form, lighter build, and coarser sculpture suggest Fusinus, in which genus the plait at base of aperture is sometimes faintly indicated also. The present shell is strikingly similar to Fusinus sp. from Bowden, Jamaica, described by Woodring (Miocene

Picture icon

Figs. 1, 1a.—Crassatellites tripliciter n.sp. Holotype, x 0.9
Fig. 2.—Serripecten tahuiana n.sp. Holotype, x 1.4.
Fig. 3.—Mauia waihaoensis n.sp. Holotype, x 1.3.
Figs. 4.—Fusinus waihaoica n.sp. Holotype. x 2.1.
Fig. 5.—Eulima hampdenensis n.sp. Holotype, x 12.3
Fig. 6.—Mathilda prima n.sp. Holotype, x 3.0.
Fig. 7.—Zexilia tenuilirata n.sp. Holotype, x 3.0.
Fig. 8.—Zexilia submarginata n.sp. Holotype, x 3.0.
Fig. 9.—Cirsotrema (Tioria) marshalli n.sp. Holotype, x 2.2.
Fig. 10.—Waihaoia striata n.sp Holotype, x 1.5.
Fig. 11.—Eocithara (Marwickara) waihaoensis n.sp. Holotype, x 2.1.

– 25 –

Molluscs front Bowden, Jamaica, part 2, p. 257, pl. 15, fig. 8), in its long, slender habit, shape of whorl, strongly incised suture, and in the nature of both axial and spiral sculpture.

All whorls are ornamented by strong, swollen, rounded axial ribs traversing their entire width and dying out rapidly at about line of suture on the body; spiral sculpture of raised threads in two series, the primary spirals coarse, ividely spaced, weak in interstices of axials, but strongly raised up on summits of axial corrugations; secondary spirals as very fine, regular threadlets (six or seven in number) between primaries, not seen without a hand-lens. Body-whorl with nine axials, penultimate whorl with eight; six primary spirals on penultimate whorl, the posterior two on all whorls very much weaker than the four anterior ones. The suture is strongly cut in and the whorls strongly and evenly convex. There are a number of long, weak lirae some distance within outer lip.

Height, 36 mm.; width, 11 mm.

Locality, greensands, McCullough's Bridge, Waihao (Tahuian).

Type (unique) in writer's colection.

Genus Eulima Risso.
Type: Turbo politus Linné.

Eulima hampdenensis n.sp. (Fig. 5).

Shell not large, smooth, glossy, axis straight; outline of spire pupoid towards summit. Whorls about seven in number, lightly and regularly convex; suture very closely clasping; later whorls faintly concave in a zone below suture. Last few whorls with a number of weak spiral threads over whole surface. Anterior part of aperture and outer lip broken away; inner lip with a thin callus. Protoconch decollated. Growth-lines retrocurrent to suture above.

Height, 9.0 mm.; width, 2.7 mm.

Locality, Hampden, North Otago (Tahuian).

Type and a fragmentary paratype in writer's collection.

Easily distinguished from other New Zealand species by convexity of whorl with clasping suture, pupoid habit, and development of spiral threads. E. waihaoensis Allan, also an Eocene species, is a larger shell with straight outlines, and of the same lineage as E. donae Ten.-Woods and E. otaioensis Laws.

Genus Mathilda Semper.
Type (s.d., Cossm.): Turbo quadricarinatus Brocchi.

Mathilda prima n.sp. (Fig. 6).

Shell of medium size, spire elevated, conic, of about eight post-nuclear whorls. Protoconch decollated. Periphery sharp, low down, strongly keeled, and carrying a heavy spiral cord; whole surface of whorls ornamented with spiral threads, the penultimate whorl with eight to ten above periphery and about four below; the threads on base much finer and closer than those elsewhere on whorl; from the posterior angle of aperture there appears a strong thread (much less prominent than the peripheral cord, however), which produces a

– 26 –

biangulated effect on the last whorl; very fine axial threads, a little sinuous and slightly antecurrent to suture above, are developed over the whole surface of the shell, causing a fine reticulation of sculpture and surmounting even the cord on periphery. Aperture circular, broadly angled behind; basal lip everted and very effuse to left; columella short, stout, vertical; a faint linear umbilical depression present; inner lip thinly callused, but not widely; outer lip notched at periphery.

Height, 11.0 mm.; width, 5.7 mm.

Locality, Hampden, North Otago.

Type (sole specimen) in writer's collection.

This, the first record of Mathilda from New Zealand, is a remarkably well preserved and exquisitely sculptured little fossil.

Genus Zexilia Finlay.
Type: Exilia waihaoensis Suter.

Zexilia tenuilirata n.sp. (Fig. 7).

Shell of average size for the genus, outlines of spire straight, apex missing; whorls about eight post-nuclear remaining, flattish, with a faint bulge below; suture not distinct. Sculpture: axial ribs (about twenty on last whorl) rounded, regularly spaced, straight, but slightly oblique, on last whorl sinuous and evanescing early on base; thin, sharp spiral lirae are well developed (seven on penultimate whorl), the posterior three more widely spaced and much stronger than the remainder, and nodulating axials at intersections. Outer lip and anterior portion of canal broken away; inner lip not callused.

Height (estimated), 23 mm.; width, 5.0 mm.

Locality, greensands, McCullough's Bridge (Tahuian).

Type (sole specimen) in writer's collection.

Z. dalli (Suter) has more bulging whorls; weaker, more numerous, and finer spirals; flexuous and more pinched up axials; axial obsolescence on last whorl.

Zexilia submarginata n.sp. (Fig. 8).

This is a larger, more heavily built shell than the foregoing species, and has the suture more distinct owing to a slight shoulder close below it, caused by a faint subsutural tumid band, which also nodulates the axials a little at their summits. It has heavier and blunter axial ribs, straight to faintly arcuate, and the interspaces are rather less in width than the ribs (in tenuilirata the interstices are wider than the axials). The nature of the spiral sculpture affords a ready means of separating these two forms. The present species has weak incised spiral lines separated by wider flat areas, about ten on penultimate whorl, and scarcely seen surmounting the axial costae. The apex, outer lip, and canal are broken away. There is a thin glaze of callus on the parietal wall.

Height (estimated), 30.0 mm.; width, 7.0 mm.

Locality, greensands, McCullough's Bridge (Tahuian).

Type (sole specimen) in writer's collection.

– 27 –

Zexilia waihaoensis (Suter).

The writer has this species from three Eocene localities—McCullough's Bridge (type locality), Waihao Downs, Hampden. The Downs shell makes a very perfect match for the type, but the shell from McCullough's Bridge is not quite typical in its spiral sculpture, for the posterior spiral on each whorl is much stronger than any of the others, and the suture therefore appears distinctly submargined.

It is worthy of note that three species of Zexilia occur at McCullough's Bridge, while only one of them is found at Waihao Downs. This recalls the case of Cordieria, still more striking, of which there are four species at the Tahuian locality and no Bortonian ones.

Genus Cirsotrema Morch.
Type: Scalaria varicosa Lamarck.

Subgenus Tioria Marwick.
Type: Cirsotrema youngi Marwick.

Cirsotrema (Tioria) marshalli n.sp. (Fig. 9).

This is an exquisitely sculptured fossil from the beds at Hampden. The apical whorls are decollated. The six remaining ones are ornamented similarly throughout by both axial costae and spiral lirations, which are much weaker than the ribs. The ribs are sharp and narrow, oblique to left, and conspicuously waved along their crests. Not far below suture they abruptly decrease in height, waved crests are absent, and the axials become weak threads traversing a fairly wide subsutural zone very much more lightly sculptured than the rest of the whorl. The spiral lirations, of which there are seven primary ones on body-whorl, are quite reminiscent of those of C. lyrata Zittel, but are stronger than those of C. youngi, the type of Tioria. The body-whorl has a low, blunt keel below periphery, and at this keel the waving of axials abruptly ceases, the ribs twisting over somewhat and diminishing considerably in strength. The intercostal spaces on the base are crossed by simple, regular, close spiral threads. Aperture circular, entire, anterior portion slightly worn; fasciole resting entirely against inner lip, no umbilicus present.

Height (estimated), 32.0 mm.; width, 12.0 mm.

Locality, Hampden.

Type (sole specimen) in writer's collection.

The greater number of axial ribs, stronger spiral sculpture, waved crests to ribs, and absence of posterior tubercle on ribs combine to distinguish this shell from youngi, the only other member of the subgenus.

Named in honour of Dr P. Marshall, who was the first to study the palaeontology of the Hampden beds.

– 28 –

Genus Waihaoia Marwick.
Type: Waihaoia allani Marwick.

Waihaoia striata n.sp. (Fig. 10).

Shell small, biconic, apex decollated, about six and a-half whorls remaining. Spire a little greater in height than aperture, tapering; suture not distinct; whorls closely clasping, faintly shouldered at upper third. Axial ribs never strong, represented as low, narrow ridges extending from anterior suture to the ill-defined shoulder, obsolete behind that; ribs on early whorls rather close, thereafter gradually becoming wider apart, until on penultimate and antepenultimate whorls the intercostal depressions are several times wider than the ribs; on penultimate whorl the ribs begin to weaken, and they are entirely absent from the body, which is quite smooth. Whole surface covered by spiral striae. Aperture long and narrow, fasciole scarcely defined, columella-plaits four, the anterior one very weak and situated well inside aperture.

Height, 45.0 mm.; width, 12.0 mm.

Locality, Hampden.

Type (sole specimen) in writer's collection.

The general form of shell and incipient axial obsolescence on later whorls seems to suggest that this species is getting on towards Teremelon, and, if so, it indicates that the Teremelon stock began to differentiate from Waihaoia as early as Tahuian times.

Genus Eocithara Fischer.
Type: Harpa mutica Lamk.

Subgenus Marwickara n. subgen.
Type: Marwickara waihaoensis n.sp.

Owing to lack of literature, the shell described below was forwarded to Dr J. Marwick along with a request for information regarding its generic location. Dr Marwick has stated that it is close to Eocithara Fischer (monotype Harpa mutica Lamk., Parisian Eocene), but that it is debatable whether the differences from Eocithara warrant generic or subgeneric recognition, for the proto-conch is eroded, and so the closeness of relationship cannot be definitely estimated. Dr Marwick has kindly compared this New Zealand shell with the genotype of Eocithara as follows:—“The Waihao Downs shell differs chiefly in having a higher spire and more twisted columella, with the canal bent away to the left, giving the aperture a different shape; but the sculpture has the same elements, namely, sharply raised sinuous axials, the interspaces with fine waved spiral threads trellised by growth ridges. The V-shaped parietal denticle is not possessed by Eocithara, which has moreover, a thicker inner lip with a projecting edge so as to form an umbilical chink. The neck has quite a different set from that of mutica the genotype or of any other species I have found pictures of. Although strongly twisted to form a prominent fasciole in Eocithara, the columella and

– 29 –

its extension callused by the thick inner lip are almost vertical. In the Waihao shell the callus is very thin and the neck is bent away to the left.”

The writer has much pleasure is associating Dr Marwick's name with this new subgenus.

Eocithara (Marwickara) waihaoensis n.sp. (Fig. 11).

Shell not large, of about four post-nuclear whorls; spire of less height than aperture plus canal, stepped below sutures. Whorls convex, drawn in rapidly to suture, giving the appearance of a rounded shoulder. Axial ornamentation of thin, sharp, sinuous ridges (nineteen on last whorl), antecurrent to suture on shoulder, where they appear as overfolds in the direction of growth; axials spaced about four times their own width apart; on the body they become weaker on the base, but persist on to the neck of the canal. Spiral sculpture is present as fine waved spiral threads, slightly trellised by growth-striae and seen only in interspaces of axials, about nineteen to twelve on penultimate whorl. Aperture long, narrow, wider behind; canal moderately long, deep, and twisted to left; inner lip considerably excavated on parietal wall, which bears a distinct raised pad of callus, on which is situated two denticles in the form of a V towards its posterior end; outer lip thickened, sinuous; columella considerably twisted to left; umbilicus entirely absent. Protoconch worn off.

Height, 23 mm.; width (estimated), 12 mm.

Locality, greensands, Waihao Downs.

Type and a fragmentary paratype in writer's collection.