Cook (2007) has pointed out that : "Bergquistia – unarmoured irciniids, with slightly fascicular and uncored primary fibres, though there may be some coring near the surface. In some areas, primary fibres are connected by secondary webs (Sim and Lee 2002). The distinction between this genus and Sarcotragus requires clarification or revision. " The descriptions of the Bergquistia species are based on one specimen only. It is thus difficult to understand the variability of each spcies. An integrative approach based on many others characters is needed.
Sim, C.J.; Lee, K.J.; Kim, Y.A. (2017). New species in two genera, Sarcotragus and Bergquistia (Demospongiae: Dictyoceratida: Irciniidae), from Korea. Journal of Species Research. 6 (Special Edition): 135-147. Available for editors [request]