Triphoris (Ino) maxillaris Hinds, 1843

Albano, Paolo G., Bakker, Piet A. J. & Sabelli, Bruno, 2019, Annotated catalogue of the types of Triphoridae (Mollusca, Gastropoda) in the Natural History Museum of the United Kingdom, London, Zoosystematics and Evolution 95 (1), pp. 161-308 : 161

Triphoris (Ino) maxillaris Hinds, 1843

Figure 31

Triphoris (Ino) maxillaris Hinds 1843b: 18, not illustrated. Illustration available in Hinds (1844): 29, pl. 8, fig. 8.

Type locality.

Straits of Malacca.

Type material.

Lectotype: NHMUK 1879.2.26.202/1, here designated (J. Lombe Taylor coll.). Paralectotypes: NHMUK 1879.2.26.202/2, 1 specimen, Malacca (J. Lombe Taylor coll.) ; NHMUK 1844.6.7.12, Malacca, 1 specimen (coll. E. Belcher) .

Original description.

Testa rosea; anfractibus 16-18, superficie laevigata, bisulcatis; marginibus sulcorum granulatis; sutura sulcata, marginibus granulatis apertura subquadrata, sinu laterali parvo patulo. Axis 5½ lin. This shell is very remarkably characterized. The surface is perfectly smooth, and of an agreeable rose-colour; but each whorl is divided into three unequal parts by two furrows. The margins of each furrow, and of the depressed line which marks the course of the suture, are provided with a series of horizontal granulations, which look towards each other and do not appear above the surface of the shell, but under a magnifying glass display an appearance which seems to justify the specific name.

Translation of the Latin text.

Pink shell; 16-18 whorls with a smooth surface with two grooves whose margins are granulated; deep suture, subquadrate aperture with granulated margin, slightly open posterior sinus. Height 5½ lines.

Diagnosis.

The lectotype is a subadult, but the paralectotype is 9.9 mm high. Shell conical and elongated. The lectotype has 17 flat whorls, but the apical part is missing. The three spiral cords have broad flat coalescent tubercles. The base has two more spiral cords with similar tubercles and a depression between the fifth cord and the siphonal canal which is short. The peristome has no additional cords and bears a shallow posterior canal. The protoconch is absent in the types, but remnants of its last whorl suggest a multispiral type. Teleoconch pink, protoconch brown.

Remarks.

Specimens with indistinguishable teleoconch sculpture, colour and overall appearance, but with paucispiral protoconch were found in Vanuatu. Consequently, we designated as lectotype of T. maxillaris a specimen that, although subadult, retains the last whorl of a typical planktotrophic protoconch (Fig. 31K, L ) to unambiguously identify this species.

Figures

Figure 31. Triphoris maxillaris Hinds, 1843. A-F, H Paralectotype, NHMUK 1844.6.7.12, Straits of Malacca (coll. E. Belcher): front (A), side (B, C), back (D), aperture (E), peristome (F), original labels (H). G, I, K, L Lectotype NHMUK 1879.2.26.202 / 1, Straits of Malacca (M rs J. Lombe-Taylor coll.): front (G), original labels (I), protoconch (K, L). J Figure in Hinds 1844. Scale bars: A-D: 2 mm; E, F: 0.5 mm; G: 1 mm; K, L: 0.1 mm.