Triphora plebeja Thiele, 1925

Albano, Paolo G. & Bakker, Piet A. J., 2016, Annotated catalogue of the types of Triphoridae (Mollusca, Gastropoda) in the Museum fuer Naturkunde, Berlin, with lectotype designations, Zoosystematics and Evolution 92 (1), pp. 33-78 : 42

Taxon classification Animalia Caenogastropoda Triphoridae

Triphora plebeja Thiele, 1925 Figure 10

Triphora plebeja Thiele, 1925: 129 (95), plate XXII (X), figure 21.

Type specimens.

Lectotype: ZMB/Moll no. 109272a from Station 100, here designated. Paralectotype A: ZMB/Moll no. 109272b from Station 100; Paralectotype B: ZMB/Moll no. 109272c from Station 101; Paralectotype C: ZMB/Moll no. 109272d from Station 106.

Type locality.

"Stationen 100 (Francis-Bucht), 101 (Algoa-Bucht) und 106 (Agulhasbank)" (South Africa).

Original description.

Schalen von den Stationen 100 (Francis-Bucht), 101 (Algoa-Bucht) und 106 (Agulhasbank) unterscheiden sich von den bisher genannten Arten durch ihre spitze, aus 5 Windungen bestehende Embryonalschale mit einer aus herablaufenden Fäden und 2 Spiralreifen bestehenden Skulptur, sie sind braun, lang kegelförmig, im ganzen mit 11 Windungen, von denen die auf die Embryonalschale folgenden 2, die übrigen 3 Reihen von Knoten aufweisen; die letzten werden kaum breiter, bei ihnen ist ein schmaler Reifen über der Naht sichtbar. Außer diesem, der die untere Kante bildet, hat die letzte Windung noch 3 glatte Reifen an der Unterseite. Spindelfortsatz und Mundrand sind beschädigt. Höhe 4,5 mm, Durchmesser 1,25 mm.

Translation.

Shells from station 100 (Francis Bay), 101 (Algoa Bay) and 106 (Agulhas Bank) are distinguishable from all the previous species by their pointy protoconch, composed of 5 embryonal whorls with two spiral keels and axial riblets; the shells are brown, long and conical, in total 11 whorls, of which the first whorls after the embryonal whorls have two rows of tubercles and the lower whorls 3 rows, the last one is barely wider, above the suture a smaller cord is visible. The base has further three smooth cords visible. Siphonal canal and aperture are damaged. Height 4.5 mm, diameter 1.25 mm.

Diagnosis.

Lectotype height 4.5 mm. Shell conical, with flat whorls. Teleoconch of nine whorls, which have three tubercled broad spiral cords; the second one appears lately, on the fifth whorl. A fine suprasutural smooth cord is also present. The last whorl has a fourth smooth spiral cord, and the base has further three smooth spiral cords. The peristome of the lectotype has been rebuilt after breaking (there is a scar, likely due to a predatory attempt), hence it is not fully reliable. Nonetheless, the sculpture of the peristome seems not to bear bifurcating ribs. Multispiral apex of five whorls; a bit worn in the lectotype; nonetheless, it clearly bears two keels and fine axial riblets on the lower three whorls. Colour light brown, the first tubercled cord looks lighter, but colours may be faded, because the specimens were dead collected.

Remarks.

This is the only species with planktotrophic apex described by Thiele from South Africa.