Melayonchis eloisae Dayrat, 2017

Dayrat, Benoît, Goulding, Tricia C., Bourke, Adam J., Khalil, Munawar & Tan, Shau Hwai, 2019, New species and new records of Melayonchis slugs (Gastropoda: Euthyneura: Pulmonata: Onchidiidae), Raffles Bulletin of Zoology 67, pp. 557-585 : 581

Melayonchis eloisae Dayrat in Dayrat et al., 2017

Melayonchis eloisae Dayrat in Dayrat et al., 2017: 1861–1870, figs. 3–8.

Type locality. Singapore, Pasir Park , 01°22.840ʹN, 103° 57.224ʹE, 1 April 2010, station 5, mangrove forest with rich litter, lobster mounds, dead logs .

Type material. Holotype, 15/10 [1011] mm, and one paratype 22/ 13 mm, by original designation ( ZRC.MOL.6499).

Additional material examined. Indonesia, Sumatra, Dumai , 01°42.838ʹN, 101°23.286ʹE, 9 October 2012, 1 specimen 23/ 14 mm [1775], station 74, mangrove forest just behind abandoned buildings, high intertidal, with many Thalassina mounds and small creeks in between ( UMIZ 00003 ) .

Distribution ( Fig. 6 ). Sumatra (new record). Other records are in Brunei Darussalam, India (Andaman Islands), Peninsular Malaysia, Singapore (type locality), and Vietnam (Dayrat et al., 2017: 1863).

Habitat. In Sumatra, M. eloisae was found in a mangrove forest, at high intertidal, with many Thalassina mounds and small creeks in between, which is its most favorite habitat (Dayrat et al., 2017: 1863). Individuals were found on tree trunks and roots.

Abundance. Melayonchis eloisae is rare in Sumatra where we only found a few specimens at one site. It is hard to predict whether M. eloisae is present or not, even in what seems a perfect habitat (Dayrat et al., 2017: 1863).

Remarks. Melayonchis eloisae was expected to be present in eastern Sumatra, given its known records on the other side of the Strait of Malacca (western Peninsular Malaysia) and Singapore. Melayonchis eloisae in Sumatra is completely indistinguishable from the individuals found elsewhere. Also, the DNA sequences of the individual from eastern Sumatra are nested within the rest of the species (Figs. 3, 4).

Figures

Fig. 6. Geographic distribution of the six known Melayonchis species. The many blue dots correspond to regions where we collected gastropods since 2010 (with several sites per dot), clearly indicating where we have not found Melayonchis (e.g., Philippines, Sulawesi, Queensland). So far, Melayonchis was only found in the Andaman Islands, on both sides of the Strait of Malacca (western Peninsular Malaysia and eastern Sumatra), Singapore, southern Vietnam, Brunei Darussalam, and Northern territory. The colours used for each species are the same as those used in Figs. 3–5.