Identification of non-indigenous marine macroalgae from New Zealand aquaria outlets

Abstract

Most vector management and research on marine bioinvasions has focused on shipping-related pathways. More recently, less obvious mechanisms, such as the aquarium trade, have been recognised as important mechanisms for marine invasions, such as for the alga Caulerpa taxifolia. In this study, macroalgal specimens were collected from aquarium shops in Auckland and Nelson. Specimens were initially identified morphologically as C. taxifolia, C. racemoasa, Coelarthrum sp. and Cryptonemia sp. DNA sequencing corroborated the identification of the Caulerpa specimens. DNA sequencing also revealed that a specimen identified as Coelarthrum sp. by morphological features was in fact most probably Chamaebotrys sp. Because of the small number of Cryptonemia sequences in GenBank for comparison, only a tentative identification for this red alga could be made. Our findings of non-native macroalgae, including C. taxifolia, in aquarium shops in New Zealand show that even strict quarantine procedures cannot completely prevent the importation of non-indigenous species. Therefore, early detection, which begins with species identification, is essential to design effective control and eradication programmes.