Conus vimineus (Reeve, 1848)

Description ⁽¹⁾

Gehäuse lang gestreckt, spindelförmig, mit ziemlich hohem Gewinde versehen, vorne stark ver-schmälert und in der Nähe der Stirn etwas zusammengeschnürt. Die Embryonalwindungen,, welche nur zum Theil überliefert wurden, sind glatt und gehen ohne Zwischenskulptur in die Mittel-windungen über. Die Anzahl der letzteren beträgt sieben. Sie sind durch eine rinnenartige Naht geschieden und werden von scharfen Spiralleisten bedeckt, unter denen sich eine kräftige befindet, welche die Naht vorne begleitet; hinter derselben folgen zwei bis drei feinere; das Ganze wird von scharf ausgeprägten und stark gebogenen Zuwachsstreifen gekreuzt. Im Profile erscheint das Gewinde fast einfach kegelig, mit schwachen Absätzen versehen. Die Schlusswindung trägt breite, flache Spiralleisten, welche oft der Länge nach durch eine Furche zertheilt werden und je nach der Tiefe dieser Furche und der Häufigkeit der Zertheilungen im einzelnen mannichfache Verschiedenheiten in der Skulptur hervorbringen. In ihren Zwischenräumen sind die Zuwachsstreifen als zarte, scharfe Querleisten entwickelt. Die grösste, unvollständig überlieferte Schale dürfte etwa 43 mm. lang gewesen sein.

Das Exemplar dieses seltenen, von den Philippinen bekannten Conus, welches ich in London vergleichen konnte, vermuthlich das Original von Reeve, stimmt mit dem hier beschriebenen
Fossile vollständig überein.

Dem Conus longurionis, welcher von dem gleichen Fundorte stammt, sieht diese Art auf den ersten Blick ausserordentlich ähnlich; doch ist ihr Gewinde weit niedriger und erscheint die
Schlusswindung nahe der Spiralkante im Profile leicht abgerundet. Ferner fehlt dieser Species die Zwischenskulptur und die Krönung der ältesten Umgänge; sodann ist statt der breiten, flachen Spiralleiste, welche bei C. longurionis die Naht hinten auf den Windungen begleitet, nur eine schmale, scharfe Leiste vorhanden, und endlich kann die Zertheilung der Spiralleisten der Schluss-windung noch zur Abtrennung dienen.

Anzahl der untersuchten Exemplare: 7. Fundort: Sonde, im Distrikte Gendingan.

The casting is elongated, spindle-shaped, with a fairly high spiral, strongly narrowed at the front and somewhat constricted near the forehead. The embryonic whorls, only partially preserved, are smooth and merge seamlessly into the central whorls without intermediate sculpture. There are seven of the latter. They are separated by a groove-like seam and covered with sharp spiral ridges, among which is a robust one that accompanies the seam at the front; behind it follow two to three finer ones; the whole is crossed by sharply defined and strongly curved growth lines. In profile, the spiral appears almost simply conical, with faint shoulders. The terminal whorl bears broad, flat spiral ridges, which are often divided lengthwise by a groove, producing manifold variations in sculpture depending on the depth of this groove and the frequency of the divisions. In the spaces between them, the growth lines are developed as delicate, sharp transverse ridges. The largest, incompletely preserved shell was probably about 43 mm long.

The specimen of this rare cone, known from the Philippines, which I was able to compare in London—presumably the original from Reeve—corresponds completely with the fossil described here.

This species looks remarkably similar at first glance to Conus longurionis, which comes from the same locality; however, its spiral is much shallower, and the terminal whorl near the spiral edge appears slightly rounded in profile. Furthermore, this species lacks the intermediate sculpture and the crowning element of the oldest whorls; instead of the broad, flat spiral ridge that accompanies the suture at the rear of the whorls in C. longurionis, there is only a narrow, sharp ridge, and finally, the division of the spiral ridges of the terminal whorl can still serve as a separating feature.

Number of specimens examined: 7. Locality: Sonde, in the Gendingan district.

Description ⁽⁵⁾

The collections from the Mekran series include a form identical to one of the most abundant fossils recently collected by M. R. Ry. Sethu Rama Rao from the Tertiary formation of Burma. A careful study of the abundant and beautifully preserved specimens from Burma clearly establishes that they all belong to a single species identical with the forms described as Conus vimineus and C. palabuanensis by Martin, and as C. subvimineus by Cossmann, and with one of the fossils described as Conus protofurvus by Noetling. Specimens occur identically with each of the above-mentioned forms, but are connected by every possible intermediate gradation, clearly establishing the specific identity of all these fossils.

I intend to consider this species in detail on some future occasion in a monograph dealing with the Burmese fauna.

The anterior termination of the shell is broken in all the available specimens from the Mekran beds. The largest specimen has a diameter of about 15 mm, corresponding to an approximate height of 42 mm

Occurrence. Mekran beds: north of Talar Gorge, on the road from Kej to Gwadar, base of the sandstones constituting the Talar Mountains; between Kanderi and Sari Dasht in Kulanch.

Remarks. Cossmann has classified this shell as a Chelyconus, probably due to the seemingly conoidal outline of the spire. Some have ventured to refer it to Leptoconus based on its close resemblance to various species of that section

Conus subvimineus (Cossmann, 1900)

Taille assez petite; forme étroite, allongée, conoïdale; spire relativement longue, à galbe d'abord extra-conique au sommet, puis graduellement conoïdal; protoconque polygyrée, lisse, proboscidiforme; tours assez larges, séparés par de profondes sutures, d'abord étagés ou plutôt imbriqués en avant, et obtusément crénelés sur ce rebord, qui disparalt peu à peu, de sorte que les tours finissent par devenir plans et subulés, ornés seulement de trois ou quatre stries spirales, finement ponctuées par les accroissements. Dernier tour égal aux trois quarts de la longueur totale, quand on le mesure à partir de la suture de l'avantdernier tour, séparé de la spire par un angle que marque une bande un peu saillante, servant de limite aux sillons spiraux de l'avant-dernier tour; galbe un peu convexe en arrière et au milieu, atténué et légèrement excavé à la base; surface à moitié lisse, ornée en avant de sillons assez rapprochés, équidistants, finement cloisonnés par les plis d'accroissement, obliquement enroulés et plus serrés sur le cou. Ouverture assez étroite, à bords presque parallèles, légèrement dilatée au milieu, anguleuse dans l'angle inférieur, terminée en avant par un canal large, obliquement tronqué sans échancrure; labre mince, à contour à peu près rectiligne, obliquement incliné à droite de l'axe, du côté antérieur, échancré sur la spire par un sinus large et peu profond; columelle faiblement tordue et excavée à la naissance du canal ⁽³⁾.

Dim. - Longueur, 24 mill.; diamètre, 8 1/2 mill. ⁽³⁾

Rapp. et diff. - Cette espèce ressemble, par son galbe, à C. vimineus Reeve, et aussi à C. longurionis Kiener, que Tryon considère comme synonyme de C. vimineus; elle s'en distingue toutefois par la surface de son dernier tour qui est à moitié lisse, dépourvu des stries qui ornent, en arrière, les deux espèces vivantes. Dans son étude sur les mollusques pliocéniques de Java, M. Martin distingue les formes fossiles, qu'il rapporte à ces deux espèces vivantes, par l'ornementation grossie des premiers tours de spire, qui seraient crénelés chez C. longurionis, tandis que l'angle imbriqué des tours de C. vimineus serait lisse; à ce point de vue, la coquille fossile de Karikal ressemblerait donc plutôt à C. longurionis; néanmoins je l'ai nommée subvimineus, parce que son galbe est plus conoidal, comme celui de C. vimineus. Assez rare; trois individus ⁽³⁾.

Rather small in size; narrow, elongated, conoidal in shape; relatively long spire, initially extra-conical at the apex, then gradually conoidal; polygyrate, smooth, proboscidiform protoconch; whorls rather broad, separated by deep sutures, initially stepped or rather imbricate at the front, and obtusely crenellated on this rim, which gradually disappears, so that the whorls eventually become flat and subulate, adorned only with three or four spiral striae, finely punctuated by the growths. Last whorl equal to three-quarters of the total length, when measured from the suture of the penultimate whorl, separated from the spire by an angle marked by a slightly projecting band, serving as the boundary for the spiral grooves of the penultimate whorl; curve slightly convex at the rear and in the middle, attenuated and slightly excavated at the base; Surface semi-smooth, ornamented anteriorly with fairly close, equidistant grooves, finely partitioned by growth folds, obliquely rolled and tighter on the neck. Aperture rather narrow, with almost parallel edges, slightly dilated in the middle, angular in the lower angle, ending anteriorly in a broad, obliquely truncate canal without a notch; labrum thin, with an almost straight outline, obliquely inclined to the right of the axis on the anterior side, notched on the whorl by a broad and shallow sinus; columella slightly twisted and excavated at the origin of the canal (3).

Dimensions - Length, 24 mm; diameter, 8.5 mm (3)

Relationships and differences - This species resembles, in its shape, C. vimineus Reeve, and also C. longurionis Kiener, which Tryon considers a synonym of C. vimineus; It differs, however, in that the surface of its last whorl is half-smooth, lacking the striations that adorn the rear of the two living species. In his study of the Pliocene mollusks of Java, Mr. Martin distinguishes the fossil forms, which he attributes to these two living species, by the enlarged ornamentation of the first whorls, which are said to be crenate in C. longurionis, while the imbricate angle of the whorls of C. vimineus is smooth; from this point of view, the fossil shell from Karikal would therefore resemble C. longurionis more closely; nevertheless, I have named it subvimineus, because its shape is more conoidal, like that of C. vimineus. Quite rare; three specimens


Conus vimineus Holotype BMNH mm. 29,0 x 10,5	Conus subvimineus ⁽³⁾ Pl. IV, fig. 9, 10 mm. 24 x 8,5 Pliocene from e well in Karikal, India The surface of its last whorl is half-smooth

Conus vimineus ⁽¹⁾ Taf. II – fig. 23, 25

Conus vimineus mm. 26,1 Pliocene Nyalindung, Java, Indonesia		Conus vimineus ⁽⁴⁾ Plate 29, figure 14 mm. 25,6 x 8,3 Pleistocene marls of station SM242 Santo, New Hebrides.