Lamprohaminoea ovalis (Pease, 1868)

Mehrotra, Rahul, A. Caballer Gutierrez, Manuel, M. Scott, Chad, Arnold, Spencer, Monchanin, Coline, Viyakarn, Voranop & Chavanich, Suchana, 2021, An updated inventory of sea slugs from Koh Tao, Thailand, with notes on their ecology and a dramatic biodiversity increase for Thai waters, ZooKeys 1042, pp. 73-188 : 73

* Lamprohaminoea ovalis (Pease, 1868) Figure 7B, C, D

Material examined.

Six individuals 9-35 mm, SB; eight individuals 6-21 mm; LB.

Ecology.

White morphs (Fig. 7B ) among rubble in shallow coral reef habitats at depths 4-8 m. Purple/red morphs in soft sediment habitats outside the coral reef where it is found strongly associated with mats of cyanobacteria on the benthos. Purple/red morphs (Fig. 7C, D ) may also be found near the reef edge when cyanobacteria abundances increase, indicating a possible seasonal influence in abundance. Often found together with other Haminoeidae species from Koh Tao, apart from Atys sp. White and purple/red morphs not found together suggesting a fundamental division in local ecology (i.e., diet), potentially contributing to the difference in colouration. Specimens from Koh Tao have been observed to be ingested, and sometimes rejected post-ingestion, by the wrasses Cheilinus fasciatus (Bloch, 1791) and Thalassoma lunare (Linnaeus, 1758). This method of prey rejection has been suggested as a vector for prey dispersal of sea slugs onto opportunistic predatory scleractinian corals ( Mehrotra et al. 2019). Depth 8-18 m.

Distribution.

Lamprohaminoea ovalis known from the Red Sea, Oman, Philippines, Vanuatu, Guam, French Polynesia, Hawaii ( Oskars and Malaquias 2020), Australia ( Nimbs and Smith 2016), Mariana Islands ( Carlson and Hoff 2003), Japan ( Hori 2017), Marshall Islands ( Marcus and Burch 1965), and invasive in the Mediterranean Sea ( Fernández-Vilert et al. 2018). It is here recorded for the first time from Thai waters.

Remarks.

With the recent comprehensive review of the genus Lamprohaminoea ( Oskars and Malaquias 2020), specimens from Koh Tao were identified as L. ovalis . This identification was based on shell morphology and external colouration, the variability of both now being well documented. Despite specimens from Koh Tao being from the same species, the different morphs have been found to exhibit distinct ecological characteristics.

Figures

Figure 7. A Haloa sp. 5 mm B Lamprohaminoea ovalis 18 mm C L. ovalis 9 mm (photograph by Elouise Haskin) D L. ovalis 4 mm E Chelidonura cf. castanea 62 mm F Chelidonura punctata 32 and 34 mm G Niparaya sp. 4 mm H Philinopsis speciosa 18 mm I ' Philinopsis ' Philinopsis coronata 35 mm (photograph by Phannee Mccarthy) J Tubulophilinopsis lineolata 38 mm K Tubulophilinopsis pilsbryi 35 mm L Tubulophilinopsis reticulata 30 mm (photograph by Kirsty Magson).