Amphidromus (Syndromus) rottiensis, Chan & Tan, 2010

Chan, S. Y. & Tan, S. K., 2010, On Two New Species Of Amphidromus (Gastropoda: Camaenidae) From The Lesser Sunda Islands, Indonesia, Raffles Bulletin of Zoology 58 (2), pp. 245-249 : 246

publication ID	https://doi.org/ 10.5281/zenodo.4508354
persistent identifier	https://treatment.plazi.org/id/A6232A41-727E-9724-FCC3-FD96FD480E9A
treatment provided by	Carolina
scientific name	Amphidromus (Syndromus) rottiensis
status	sp. nov.

Treatment

Amphidromus (Syndromus) rottiensis View in CoL , new species

( Figs. 1 View Fig G–I)

Material examined. – Holotype – 1 ex. ( MZB.Gst.15.047, Ex BMNH20080621 ), arboreal on shrubs and trees in mesic hilly forest, southwestern central plateau portion (Busalangga) of Rotti Island (Pulau Rote), Indonesia, coll. John Abbas, Apr.2008.

Paratypes. – 2 ex. ( MZB.Gst.15.048) ; 3 ex. ( ZRC.MOL.2837–2839) ; 2 ex. ( MNHN) ; 8 ex. ( CSY409.003 amph049.00/01–08) ; 3 ex. ( BMNH20080622 ) – same data as holotype .

Description. – Shell sinistral, rather solid and robust, opaque, smooth with glossy lustre and oblong-conic; whorls (5.5–6) rather rounded; apex black, appearing as a spot at tip of spire; outer lip thin and slightly reflected; columella white and reflected over, and partially covering the umbilicus; aperture relatively large, slightly less than half that of total shell height; peristome white; outer lip profile straight when viewed from the side; parietal wall very thin and transparent, the underlying colours and bands visible; colour and patterns variable; ground colour light yellow or white. Three main colour morphs have been observed, the predominant form is with disjunct black radial streaks or variegated dashes in the antepenultimate and penultimate whorls that are crossed or bisected by a yellow spiral band; a black spiral line above the suture and a pinkish subsutural spiral band (which may fade with age) is present in most examined specimens; patterns clearly visible on the inside of the aperture.

Distribution. – Known so far only from the type locality.

Etymology. – This species is named after the type locality with Latin suffix - ensis denoting place.

Remarks. – Rensch (1932), and Laidlaw & Solem (1961), mentioned only Amphidromus (Syndromus) contrarius ( Müller, 1774) from Rotti Island. Amphidromus (Syndromus) contrarius ( Müller, 1774) ( Fig. 1D View Fig ) with the black apical spot and pinkish subsutural spiral band is morphologically most similar to Amphidromus (Syndromus) rottiensis , new species. However, the relatively shorter and stouter Amphidromus (Syndromus) rottiensis , new species, can be easily distinguished by the lack of a calloused nodule/ subtriangular tubercule on the posterior end of the parietal wall which is a distinctive character of Amphidromus (Syndromus) contrarius ( Müller, 1774) (see Laidlaw & Solem, 1961; Fig. 1D View Fig ). The presence of a black line above the suture is also diagnostic of Amphidromus (Syndromus) rottiensis , new species. Dark axial bands marking interruptions in shell development (varices) were absent in all examined specimens. Amphidromus (Syndromus) rottiensis , new species, differs in having black apical whorls, white ground colour and total absence of dark axial bands as compared to another similar looking species, Amphidromus (Syndromus) poecilochrous Fulton, 1898 ( Fig. 1F View Fig ) which is distributed in the islands of Komodo, Sumbawa, Flores, Adonara, and Lemabata. Certain forms of Amphidromus (Syndromus) rottiensis , new species, may also be mistaken for similarly-coloured specimens of Amphidromus (Syndromus) poecilochrous jaeckeli Laidlaw , in Butot, 1954, which however, lacks the black apical spot. The holotype was designated BMNH 20080621 in Chan et al., 2008, but has since been reassigned to MZB.Gst.15047.