Triphoris (Ino) gigas 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

publication ID	https://dx.doi.org/10.3897/zse.95.32803
publication LSID	lsid:zoobank.org:pub:0F66F482-B7AB-4A5C-A611-68EC01012D41
persistent identifier	https://treatment.plazi.org/id/4ACCAEC6-00DB-A1B4-6273-0A13A61D6FA9
treatment provided by	Zoosystematics and Evolution by Pensoft
scientific name	Triphoris (Ino) gigas Hinds, 1843
status

Treatment

Figure 29 View Figure 29

Triphoris (Ino) gigas Hinds 1843b: 17, not illustrated. Illustration available in Hinds (1844): 28, pl. 8, fig. 1.

Type locality.

New Guinea.

Type material.

Syntypes: NHMUK 1879.2.26.194/1: 1 specimen, New Guinea, (coll. T. Lombe Taylor) .

Original description.

Testa valde elongata; anfractibus 25-28 planulatis, quadriseriatim granulosis, inferior paululum maxima ad basin granulorum punctatis. Axis 11 lin.

Geog. New Guinea; dredged from a muddy bottom at 18 fathoms.

This is the largest species with which I am acquainted. The colour would appear to be brown, but, as the specimens are dead, they cannot be relied on.

Translation of the Latin text.

Shell very elongated; 25-28 plain whorls with four rows of granules, the lowest a little bit larger, base dotted by granules. Height 11 lines.

Diagnosis.

Syntype broken into two pieces: the abapical and apical ones are 9.5 mm and 3.7 mm, respectively. Shell extremely elongated, cylindrical, with very flat sides. Whorls with four tuberculated spiral cords. The first is initially smooth. The third cord develops later and initially just as a fine thread. Axial ribs prosocline. Apex and base lacking in the available syntype. Syntype background teleoconch colour white, with orange blotches, but likely faded; the original figure shows a deeper brown-orange colour.

Remarks.

A “potential” lectotype ( NHMUK 196542) had been selected by S. Kosuge in 1965 but then lost while on loan to B. Marshall in 1979. This lectotype designation has never been published and is not deemed valid (as many other “potential” lecto- and paralectotypes of triphorids in NHMUK). A photograph (negative no. 0810) is available (Fig. 29A View Figure 29 ) and shows a specimen which hardly matches the original description and the figure by Hinds (1844) in the Zoology of the Sulphur. In particular, T. gigas is characterized by three tuberculated spiral cords of equal size plus a smaller subsutural one, while the lost “potential” lectotype has clearly two main cords and a smaller subsutural one. The lot NHMUK 1879.2.26.194 contains two specimens belonging to two different species. The first specimen (Fig. 29F, I, J View Figure 29 ) likely belongs to T. gigas : it is a juvenile specimen and the third cord is visible between the second and the last as a fine thread (see under T. princeps Sowerby III 1904, Figure 97F View Figure 97 , the unidentified specimen that is likely a mature T. gigas ). The second specimen (Fig. 29D, E View Figure 29 ) has more rounded whorls with two tuberculated spiral cords and strong smooth supra- and subsutural spiral cords which do not appear in T. gigas . Lot NHMUK 196543 (Fig. 29B, C View Figure 29 ) was also labelled as "potential lectotype " but the shell is more conical and an additional spiral cord develops lately between the first and the second, instead of between the second and the third like in T. gigas .