sulfonoida

Sulfonoida are an order within the class Ascidiacea, which comprises a group of marine invertebrate animals commonly known as tunicates or sea squirts. These organisms are part of the phylum Chordata, making them relatives of vertebrates, despite their simple, sac-like body structure. Sulfonoida are characterized by their distinct siphons used for water intake and expulsion, facilitating filter-feeding of plankton and microscopic particles from the surrounding seawater.

Members of Sulfonoida typically possess a flexible, tunic-like outer covering made of a cellulose-like carbohydrate called tunicin. Their bodies are sessile, attaching permanently to substrates such as rocks, shells, or submerged structures in their marine environments. The internal structure includes a pharyngeal basket with numerous perforations, which plays a key role in their filter-feeding mechanism by trapping food particles as water passes through.

Ecologically, Sulfonoida are important as filter feeders that help maintain water quality in marine ecosystems. They often form dense colonies, providing habitat and food for various marine species. Their distribution spans a broad range of oceanic habitats, from shallow coastal waters to deeper offshore zones.

Reproductively, Sulfonoida exhibit both sexual and asexual modalities. They release eggs and sperm into the water column for external fertilization, with larvae that are free-swimming before settling and metamorphosing into sessile adults. Some species can also reproduce through budding, contributing to colony expansion.

Research on Sulfonoida contributes to understanding chordate evolution, as these tunicates share significant developmental and genetic similarities with vertebrates. Their unique biological features continue to be studied within developmental biology and marine ecology.