Art. 7.—Some Remarks on New Zealand Calliostomidae, with Descriptions of New Tertiary Species.
[Read before the Otago Institute, 8th November, 1921; received by Editor, -5th December, 1921; issued separately, 8th February, 1923.]
Amongst the fossil shells from Dowling Bay (see p. 106 of this volume) was a small trochoid form which could not be placed in any New Zealand species so far described. Its appearance was, however, reminiscent of a shell found at Ardgowan, near Oamaru, and -on looking up references it was found that this shell also was undescribed. It was evidently a Calliostoma, but no species of this genus is mentioned in Suter's Ardgowan list, the only trochoid shells given being two new species of Basilissa, so that either this shell had not been collected or it had been placed in Basilissa and not yet described. Several fragments of the same species were found at Target Gully, also one or two fragments of - another Calliostoma. In Suter's Target Gully list the only shells that might be connected with these species are Trochus tiaratus Q. & G., Calliostoma n. sp., Basilissa n. sp. Now, although Trochus tiaratus Q. & G.. has a superficial resemblance to the Ardgowan shell, it is totally different when the details of the aperture are compared, but a small fragment of the body-whori. might easily be mistaken for this Trochus. The author has never found T. tiaratus Q. & G. at Target Gully, nor does it occur in material of Marshall's collecting, deposited in the Otago University School, of Mines, nor amongst the Target Gully specimens in the Geological Survey collection. It is first mentioned in this connection by Marshall and Uttley (1913), who (due probably to Suter's identification) record it from Awamoa, Target Gully., Ardgowan, Puketui, and the Devil's Bridge—every locality they —visited—and mention it (inter alia) as not having previously been recorded below Pliocene beds. In a later publication (1914) the same authors give a fuller list, revised by Suter. and in it are recorded T. tiaratus Q. & G. and Trochus n. sp. In a still fuller list (1915, p. 378) Marshall records only T. tiaratus Q. & G. Finally, in the list in N.Z. Geol. Surv. Bull. No. 20 and Pal. Bull. No. 8 the final record is T. tiaratus Q. & G. and T. chathamensis (Hutt.). The latter can be easily identified, and certainly does occur there. Park (1918, pp. 88, 90, 93) listed T. tiaratus from Awamoa, Ardgowan, and Pukeuri also, but these records are only copied from Marshall and Uttley's original paper; and, in answer to a letter, Mr. Marwick wrote to the author that “ there do not appear to be any specimens [of T. tiaratus] in the Survey collections from any Oamaruian localities.”
Now, in Pal. Bull. No. 8, 1921, which is as complete an account as possible of the molluscan lists from all the New Zealand localities, the
occurrence of T. tiaratus is mentioned in seven different localities: Bryant's Farm (Gisborne), Scinde Island, Petone, Wanganui, Motunau beds, Cape Wanbrow, and Target Gully. All these except the first and last are Pliocene or Pleistocene. In the first case an impression only was found, and this is marked “ doubtful”; in the last case it appears to the author that T. tiaratus is a very doubtful record, probably copied, without revision, from incorrect early lists. Besides these occurrences, there are two more in the Trans. N.Z. Inst. The first (Thomson, 1920, p. 393) is in the Pliocene Greta beds, and the second is in a final list given by Speight (1917, p. 355) at the close of his paper on the Trelissick beds, but it is not mentioned in any of the component lists elsewhere in the paper, and has probably crept in as an error. From this evidence it is seen that there is as yet no published reliable record of T. tiaratus Q. & G. in any New Zealand beds older than the Pliocene, and that this species, therefore, is not a Miocene form. Suter's record from Target Gully was probably based on a fragment of one of the new Calliostoma species described in this paper.
This leaves us with Calliostoma n. sp. and Basilissa n. sp. In the Otago School of Mines collection are some small fragments labelled in Suter's handwriting, “Calliostoma, very likely n. sp., Target Gully,” and these are probably the original specimens, for the first mention of a Calliostoma from this locality occurs in Bulletin No. 20, and Mr. J. Mar-wick wrote saying, “ As regards the Calliostoma n. sp. of Park's list, I do not know what shell is referred to, but it is probably one of your species so labelled by Suter previous to his introduction of Basilissa. I have not come across it in any of Park's collections.” What there is left of these shells agrees perfectly with fragments” in the author's collection from Target Gully, and there is no doubt that Suter was correct in referring this shell to Calliostoma. This species, though identical with the Dowling Bay shell and a form rather rare at Ardgowan, is different from the other species mentioned from Target Gully, which is also rather common at Argdowan. Inquiry made of Mr. Mar wick elicited several interesting points about this second form. He managed to place the shell as identical with-specimens in the Geological Survey collection from Target Gully and also Ardgowan, and labelled by Suter “ Basilissa n. sp.” In this collection was also another shell, which is Suter's second species of Basilissa from Ardgowan, and which differs from all the author's specimens. Regarding Basilissa, Mr. Marwick says, “It is hard to understand why Suter classed these shells as Basilissa. In the “ Challenger ” Report, Zoology, xv, p. 96. Watson, the author of this genus, gives the following description:—
“Basilissa: Shell conical, carinated, umbilicated, nacreous; last whorl sinuated above; pillar straight, and in its direction but little oblique, thin, hollowed out above, in front hardly toothed, but at the base strongly angulated’; mouth rhomboidal, outer and inner lips do not approach one another nor are united by any palatal callus. The special feature of this genus is the sinus in the outer lip near its, insertion.
“ There is no trace of this sinus shown by the growth-lines, nor is there an umbilicus, so I think the classification as Calliostoma is much more suitable.”
There is one more record of Basilissa that the author has come across, and that is a shell in the Otago University School of Mines collection, labelled again in Suter's handwriting, “ Basilissa n. sp., Target Gully.
Fig. 1, a, b, c.—Callzostoma suteri n. sp. Holotype (a), Ardgowan, and two para-types (b, c), Target Gully. X 3.
Fig. 2, a, b, c.—Calliostoma suteri fragile n. subsp. Holotype (a.) and two para-types (b, c), Ardgowan. X 3.
Fig. 3.—Calliostoma cancellatum. Holotype, Ardgowan. X 3.
Fig. 4.—Calliostoma marwicki. Holotype, Ardgowan. x 3.
Fig. 5, a, b.— Calliostoma tindulatum. Holotype (b) and paratype (a), Castlecliff. X 2.
I have specimens, also collected by Professor- Park.” But unless the contents of the tube have been changed this identification is worse still, for the shells in the tube belong to one of the new species named by Suter himself in the Target Gully list as “ Bezanconia (Ataxocerithium) 2 n. spp.”
We can therefore safely say that, so far, Basilissa Wats, has not been correctly recorded from New Zealand, and this genus must. be omitted from our faunal lists.
The foregoing remarks show that Calliostoma has been denied its proper place in the New Zealand Tertiary. The author has studied all the available specimens of the genus from New Zealand Tertiary localities (his best thanks are due to Dr. P. Marshall for generously forwarding him all the specimens in his possession), and as a result proposes four new species and one new variety.
Calliostoma suteri n. sp. (Plate 10, fig. 1, a, b, c.)
Shell small, conical, rather solid, imperforate. Closely beaded, subequal spirals present, four strong ones on body-whorl about twice their width apart, with or without a much finer and less strongly beaded riblet intercalated between them; the nodules on lowest rib rather larger but only slightly more numerous than on the upper three. On base there are seven or eight beaded spirals subequidistant, with rarely a few much finer interstitial riblets. Spire straight, apical whorls missing, last whorl rather bluntly angled at periphery, base flatly convex. Suture slightly impressed Aperture subrhomboidal, oblique, lirate within, sides thick (especially basal one) till near the edge, then, narrowing rapidly where the” callus stops, to a sharp, crenulate edge. Columella arcuate, oblique, slightly pearly, ending suddenly in slightly reflexed angle with basal lip. Inner lip spreading over umbilical tract as a thin callus, uniting ends of peristome.
Height (estimated), 11 mm.; width, 11 mm. (Imperfect holotype.)”
Holotype, from Ardgowan, and several fragmentary paratypes, from Target Gully, in author's collection. Also a specimen, forwarded by Dr. Marshall, from Awamoa, which differs only in its slightly more convex base, due probably to adolescence.
Remarks.—This is the shell named by Suter in the Target Gully list (N.Z. Geol. Surv. Bull. No. 20) as Calliostoma n. sp.
The author has had an opportunity, through the .kindness of Mr. P. G. Morgan, of examining the type specimen of C. acutangulum Sut., and the following differences may be noted: The new shell has strong nodules, almost spinose in some specimens, while G. acutangulum has-them much ‘lower and blunter; not so prominent as the figure (Pal. Bull. No. 5, pl. xi, fig. 3) makes them appear. Those on the third rib (counting from the apical end) are more than one and a half times as numerous as those on the first rib; the second and fourth ribs having an intermediate number. This fact, together with the backward slope of the- nodules on the upper three ribs and the distinctly forward slope on the lowest rib, gives the sculpture a much less regular appearance than in C. suteri. Distinct beading on the basal ribs occurs only near the umbilical’ area, .whereas all the basal spirals in C. suteri are strongly granose. The suture in C. acutangulum is more prominent, due to the greater- distance between it and the highest rib. Mr. J. Marwick, who also compared the two shells, agreed with the author, and added, “ I think if. we had better specimens from this locality” that more differences would be found—for
example, in the disposition of the columella, which is somewhat obscured in the holotype of G. acutangulum. Specific rank for your shell is, in my opinion, justified.
The shell is named after New Zealand's pioneer in modern conchology.
Calliostoma suteri var. fragile n. var. (Plate 10, fig. 2, a, b, c.)
1918. Basilissa n. sp. (Sut.), N.Z. Geol. Surv. Bull. No. 20, pp. 90, 94.
Shell thin and fragile, imperforate. Protoconch of a little over one whorl, granulated, not shining (indicating probably a previous horny envelope), nucleus globose and generally a rather prominent varix just before brephic stage, which commences with two spiral carinae, and many unequal longitudinal ribs; during second post-embryonic whorl a third carina develops on upper shoulder, and a fourth at suture below. On all following whorls there are four main spiral ribs, the lowest being strongest and margining suture, in gerontic stage further lesser spirals develop: the largest fragment has eight unequal ribs on last whorl,’ the four main ribs three or more times their width apart. The first five post - embryonic whorls also axially ribbed, axials slanting irregularly backward, thin and sharp, nodulous where they cut the spirals. They become weaker, and faint growth-lines take their place on sixth whorl, but nodules persist, about sixty on ninth whorl. Base irregularly sculptured, but generally three close, smooth spirals at edge, very near nodular peripheral rib, innermost usually much the strongest: then a space of about quarter width of base almost smooth, then about four more strong, nodulous spirals round umbilical tract: the whole base crossed by parabolic growth-lines. Spire acute, almost twice height of aperture, outlines straight above, becoming rapidly more concave below: whorls nine to ten, body-whorl sharply angled at periphery, base flatly convex. Suture generally marked only by prominent peripheral rib and smooth concave infrasutural space. Sides of aperture uniformly thin, nacreous and lirate within. Columella oblique, with slight tubercle at base, even less reflexed and notched than in c. suteri. Inner lip extending as a slight callus over umbilical tract; not crossing parietal wall. Umbilical depression very slight.
Height, 11 mm.; height of aperture, 4 mm. Diameter—major, 11 mm.; minor, 9 mm. Holotype: Diameter—major, 15 mm.; minor, 13 mm. (fragment of a large specimen).
Holotype and many imperfect paratypes from Ardgowan in author's collection. Also found at Pukeuri (specimen in Dr. Marshall's collection) and at Target Gully.
Remarks.—Mr. Marwick reported on this shell, “ This is the Basilissa n. sp. of Park's Target Gully list, and one of those in his Ardgowan list. This shell has the secondary moniliform spirals coming in on the later whorls, as is the case with G. acutangulum Suter; but its concave outline, sharper beads, thinner spirals, and the .tendency to a smooth band on the base render it more easy of separation than is the case with the previous species.”
Calliostoma cancellatum n. sp. (Plate 10, fig. 3.)
Shell fairly solid, imperforate, outlines pagodiform. Only two whorls of the unique specimen remain, but the sculpture of these is very distinctive. Both spirals and axials are very strongly developed, sharp and thin, giving
a prominent cancellated appearance to the shell. There are four of these spirals on each whorl, with no interstitials, but the lowest is weakened and on the spire-whorls hidden by the whorl below, so that these whorls-have only three spirals. Axials, though strong, only half the -width of spirals, straight between suture and rib above and below it, but decidedly sloping backwards elsewhere, forming laterally compressed nodules at intersections with spirals, those on lowest rib of body-whorl smaller but equal in number to those on upper ribs. Base with one very prominent moniliform rib just inside periphery, then a totally smooth concave space, then four nodulous umbilical ribs, the inner two being much closer and finer, but, as body-whorl is missing, this is probably not the true basal sculpture. Suture rendered false-canaliculate by the prominence of the spirals. Sides of aperture thick, columella less, oblique than in G. suteri, little reflexed, but with a rather prominent basil notch.
Height (estimated), 10 mm.; width, 6 mm. (Imperfect holotype.)
Holotype, from Ardgowan, in the author's collection.
Calliostoma marwicki n. sp. (Plate 10, fig. 4.)
1918. Basilissa n. sp. (Sut.), N.Z. Geol. Surv. Bull. No. 20, p. 60.
Shell fairly solid, acutely conical, imperforate. Protoconch lost in the unique specimen; first remaining whorl with two carinae, one at periphery, the other margining suture below, and having distant, small, hollow nodules; traces of a line margining upper suture, and this on the next whorl becomes another spiral rib almost equal in size to the lower two; all the ribs strongly nodulous. At the same time a faint line margining lower suture begins to develop, and on following whorl, becomes a fourth prominent nodulous rib; thin and sharp axials now begin to connect nodules. The main ribs continue subequal in size, but later on a thin interstitial riblet is intercalated between each pair, axials become suddenly obsolete, and, though nodules of the three upper main spirals remain in backwardly sloping, rather, distant rows, those of lowest rib and interstitials increase in number till the proportion is about 3: 2. ‘Base with strong moniliform spiral rib inside periphery, with a linear smooth rib between the two, then a slightly concave space with about nine smooth low spirals, then three prominent moniliform umbilical ribs. Spire high, two and a half times height of aperture, slightly convex. Whorls about eight, base very slightly convex. Suture excavated, in upper whorls, slightly’ impressed in lower, submargined below and above. Aperture subrhomboidal, outer and basal lips thin, straight, meeting at a sharp angle; columella almost straight, slightly twisted, rather strongly reflexed and basally notched, inner lip spreading as a callus over the parietal wall but not reaching outer lip.
Height, 7·5 mm.; width, 4·5 mm.
Holotype, from Ardgowan, in the collection of the New Zealand Geological Survey.
Remarks.—This shell is an extreme form of Calliostoma, and approaches certain sections of Gantharidus. Mr. Marwick mentions (in litteris) that this is the second Basilissa sp. of Park's Ardgowan list, and that the basal ornamentation shows it is a close ally of G. cancellatum (vide ante), though the spire sculpture is very different.
The author's thanks are due to Mr. P. G. Morgan and Mr. Marwick for permission to describe this shell, and it is named in honour of the latter gentleman, whose help and criticism have been invaluable.
Calliostoma undulatum n. sp. (Plate 10; fig. 5, a, b.)
Shell conical, imperforate, rather fragile. Protoconch loat and spire much eroded in both specimens seen,” but spire-whorls roundly carinated a. little above suture, giving the shell a slightly undulatory outline, and bear at first only three nodulous spirals, with later on a much finer nodulous riblet intercalated between each pair, and there is indication that in fully adult specimens the principal spirals may increase to four. The top spiral. margins the suture above, and the spirals increase in size from this suture downwards. The lowest spiral does not margin the suture, and there is no strong nodulous rib at the periphery, its place being taken by about four fine almost smooth spirals, which lie between the lowest main rib and the first distinct moniliform basal rib—only about two of these riblets can be seen above suture on spire-whorls. Rather blunt and inconspicuous axials connect nodules on upper whorls, but their place is taken later by fine growth-lines. Base with about nine subequal not prominent moniuform ribs, generally with a much finer thread intercalated between each pair. The two inmost basal ribs closer together, but otherwise umbilical tract not prominently marked. Whorls about eight, base almost flat. Suture slightly excavated, margined below. Aperture trapezoidal, outer and basal lips thin and straight, meeting at a blunted angle of about 70. Columella straight, only slightly reflexed, covered with callus which does not extend over the parietal wall, basal notch slight.
Height, 11 mm.; width, 9·5 mm. (Imperfect paratype.)
Both specimens are from Castlecliff, near Wanganui, and are in Dr. P. Marshall's collection. The better-preserved one is chosen as holotype. The species is very close to G. pelluddum Val., which differs, among other things, in its coarsely-ribbed periphery and sharper outlines near apex.
The species of Calliostoma just described fall into a rather well-defined group so far as New Zealand representatives of the genus go. The members agree in having small shells, a rather acute spire and sharp peripheral angle, small protoconch, and only slight development of umbilical callus; but the prominent feature is their sculpture. They all have typically three or four main spirals and secondary interstitials, these being generally cancellated on earlier whorls by thin, sharp axials. Three fossil members of this group have already been described — viz., C. hodgei (Hutt.), C. ponderosum (Hutt.), and G. acutangulum Sut. G. hodgei is very similar to G. suteri fragile, but comparison with the type of C. hodgei in the Otago University Museum, kindly lent to me by the curator, Dr. Benham, and another specimen borrowed from Dr. Marshall's collection, showed the following differences: While the new shell has four spirals on all but the first two post-embryonic whorls, the lowest being prominent, strongly and closely nodulous, G. hodgei has three main spirals for at least four whorls after the protoconch, increasing to about six subequal main ribs on the body-whorl, the upper five with rather distant nodules, but the lowest rib on-the later whorls is practically smooth. Also, for adult specimens of about eight whorls, C. hodgei is twice the size of C. suteri fragile, and has a straight and much more callused columella. G. ponderosum (Hutt.) has three, increasing to about six smooth spirals, and is a much larger shell than any others in the group. (For comparisons with G. acutangulum Sut. see remarks under the diagnoses of C. suteri and its variety fragile.)
The eight members of this group can be tabulated thus:—
|A. With three main spirals on most whorls:|
|(a.) Spirals smooth, shell large||C. ponderosum.|
|(b.) Spirals nodulous:|
|(i.) Axials very conspicuous, cancellating the spirals||C. cancellatum.|
|(ii.) Axials inconspicuous:|
|Periphery with several fine, blunt riblets below a stronger, nodulous rib||c. undulatum.|
|Periphery with one smooth, sharp rib||c. hodgei.|
|B. With four main spirals on most -whorls:|
|(a) Spire concave, especially in lower whorls, sculpture delicate||C. suteri var.|
|(b.) Spire straight or lightly convex:||fragile.|
|(i.) Suture marked, nodules on third rib most numerous||C. acutangulum.|
|(ii.) Suture inconspicuous|
|Nodules on the two lowest ribs in the ratio 2: 3,|
|spire high as in Cantharidus||C. marwicki.|
|Nodules on the two lowest ribs subequal in|
|number, spire-angle much wider||C. suteri.|
These eight shells show a very close similarity to one another, and it may be questioned whether most of them do not belong to one very variable species, which alters its habit remarkably under different conditions. The author does not think this view tenable, especially in view of the occurrence of different members at the same locality and the same member in very different localities, but what is practically certain is that, in New Zealand, Calliostoma was, during the Oamaruian, in a highly plastic evolutionary state, and produced several members closely similar at the time, but whose Pliocene and Recent descendants differ widely. It must be borne in mind that the possibilities for variety in Calliostoma are slight: the ornament is very simple, so that small differences in it, coupled with other differences such as are found in the spire and columella, rank as high as conspicuous differences would in a complicated sculpture. C. hodgei, though distinct from G. suteri fragile, probably evolved from it, and very likely a branch of the same stock gave rise to the Recent C. pellucidum (Val.), and perhaps also to C. selectum Chem. This tri-or tetra-lirate group seems to have died out in New Zealand, for. all our Recent shells have polyspiral sculpture, though their embryonic whorls show their probable descent. It remains to be seen in the future whether the component members of the group will be of use for zonal purposes, for the author has not at present sufficient material from enough localities to’ settle this point.
List of Papers cited
Marshall, P., 1915.- Cainozoic Fossils from Oamaru, Trans. N.Z. Inst., voL 47, pp. 377–87.
Marshall, P., and Uttley, G. H., 1913. Some Localities for Fossils at Oamaru, Trans. N.Z. Inst., vol. 45, pp. 297–307.
Marshall, P. 1914. Localities for Fossils near Oamaru, Trans. N.Z. Inst., vol. 46, pp. 279–80.
Park, J., 1918. The Geology of the Oamaru District, N.Z. Geol. Surv. Bull. No. 20.
Spetght, R., 1917. The Stratigraphy of the Tertiary Beds of the Trelissick or Castle Hill Basin, Trans. N.Z. Inst., vol. 49, pp. 321–56.
Thomson, J. A., 1920. The Notocene Geology of the Middle Waipara and Weka Pass District, Trans. N.Z. Inst., vol. 52, pp. 322–415.