Identification of an aquaculture poriferan "Pest with Potential" and its phylogenetic implications

Abstract

Correct identification and classification of sponges is challenging due to ambiguous

or misleading morphological features. A particular case is a blue keratose sponge

occasionally referred to as the ``Blue Photo Sponge'' among aquarists, which appears

frequently (and in several cases unintended) in private aquaria. This spicule-less species, occasionally specified as Collospongia auris Bergquist, Cambie & Kernan 1990, not only displays a high phenotypic plasticity in growth form and colour, it also proliferates in aquacultures under standard conditions unlike most other sponges. Therefore, this species is regarded as a pest for most aquarists. In turn, the ease of cultivation and propagation in aquacultures qualifies this species as a model organism for a wide array of scientific applications. For these purposes, correct identification and classification are indispensable. We reconstructed ribosomal gene trees and determined this species as Lendenfeldia chondrodes (De Laubenfels, 1954) (Phyllospongiinae), distant to Collospon- gia auris, and corroborated by skeletal features. Additionally, the resulting phylogeny corroborated major shortcomings of the current Phyllospongiinae classificationits consequences are discussed.