Material. Sta. CP 1646: 4 spms.
Remarks. Currently, two subspecies are recognized within O. valenciennesi, the nominate Indo-Pacific form and the Atlanto-Mediterranean O. valenciennesi rufescens Koehler, 1896. The differences between these are more rugose disk granules and longer adoral shields in the nominate subspecies (Paterson 1985). Mortensen (1933 b) observed a large variability in the oral shields of Atlantic specimens, which he referred to rufescens, because he found them different from typical valenciennesi. This distinction cannot be maintained though, since Pacific specimens fall within the variability of rufescens (O'Hara & Stöhr 2006, and Lifou material). Given the high variability of several characters it is possible that these forms represent a species complex, but a subspecies distinction cannot be maintained.
The delimitation of Ophiotreta from Ophiacantha rests mainly on the usually spatulate shape of the distal oral papilla in Ophiotreta (Verrill 1899 b). This character has however also been shown for Ophiacantha bidentata (Bruzelius, 1805), the type species of Ophiacantha (Martynov & Litvinova 2008). Another generic character, the flat and serrated arm spines, is shared by Ophiopristis, of which Ophiotreta originally was a subgenus (Verrill 1899), and by Ophiocopa, suggesting possible affinities between these genera, which were placed in three different subfamilies (Paterson 1985). This may be additional evidence supporting Martynov's (2010 b) decision to drop the subfamilies.