Phylogenetics
As mentioned, the family Rissoidae supports a global distribution of small, marine and brackish species. Classifying members of the Rissoid family, based on morphological characteristics, has proven to be very difficult. The diverse form, small size and convergence of characteristics have proven to be the trickiest obstacles in Rissoidae classification. The gastropod at the focus of this study shows the morphological characteristics of the family Rissoidae. On the genus level it becomes much more difficult with similarities to the genera Voorwindia and Setia.
The main issue with classifying the unidentified Rissoidae to Voorwindia is the development processes. The unidentified specimen demonstrates direct development; whilst Ponder (1985) explains that all Voorwindia have planktotrophic larvae. Setia on the other hand do show direct development but have not been sampled near Australia (Avila, 2013). This does not mean they aren't present but is a limiting factor when trying to determine the unidentified gastropods genus. Voorwindia on the other hand have been sampled in numerous areas of Australia's east coast, which would make them a good candidate if it wasn't for its development characteristics (Ponder, 1985).
Kingdom: Animalia
Phylum: Mollusca
Class: Gastropoda
Order: Littorinimorpha
Sub-Order: Mesogastropoda
Superfamily: Risooidea
Family: Risoidae
genus: Unknown (Perhaps Voorwindia or Setia)
Species: Unknown
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