Aspiraculata | |
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Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Subphylum: | Tunicata |
Class: | Sorberacea |
Order: | Aspiraculata |
Family: | Hexacrobylidae |
Genera and species | |
See text. |
Sorberacea were a monoorder and monofamilial class of benthic Tunicates. The single order of the class was Aspiraculata, and the single family of that order was Hexacrobylidae. In a taxonomic revision of the Tunicata in 2007, the name "Hexacrobylidae" was declared invalid and members of the family were included in the family Molgulidae in the class Ascidiacea. [1] [2]
They superficially resemble sea squirts but prey on invertebrates such as crustaceans. They also have some unique physical features that distinguish them from the ascidiaceans, including a severely reduced pharynx, the retention of the dorsal nerve cord as adults, the superficial position of their ganglion and the unique histology of the cells of their digestive tracts. The branchial syphon is large and surrounded by six large lobes; the cloacal syphon is small. They live exclusively in deep water and range in size from less than one inch (2 cm) to 2.4 inches (6 cm).
Contrary to almost all tunicates, the members of this group are not filter-feeders, and instead capture and eat nematodes and small crustaceans. They are solitary animals, found only in the deep sea. [3]
Order Aspiraculata
Ascidia is a genus of tunicates in the family Ascidiidae.
Microcosmus is a genus of tunicates in the family Pyuridae, containing the following species:
Molgula, or sea grapes, are very common, globular, individual marine tunicates roughly the size of grapes.
Phlebobranchia is an order of sea squirts in the class Ascidiacea, first described by Fernando Lahille in 1886.
Stolidobranchia is an order of tunicates in the class Ascidiacea. The group includes both colonial and solitary animals. They are distinguished from other tunicates by the presence of folded pharyngeal baskets. This provides the etymology of their name: in ancient Greek, στολίς, ίδος means the "fold" of a cloth. Stolidobranchian sea squirts are also characterized by the complete absence of an abdomen. The abdominal organs of other tunicates are instead located to one side of the pharyngeal basket in this group.
Aplousobranchia is an order of sea squirts in the class Ascidiacea, first described by Fernando Lahille in 1886. They are colonial animals, and are distinguished from other sea squirts by the presence of relatively simple pharyngeal baskets. This provides the etymology of their name: in ancient greek, ἁ.πλοος-ους (ha.ploos-ous) means "simple". The posterior part of the abdomen contains the heart and gonads, and is typically larger than in other sea squirts.
Pycnoclavella diminuta, known as the white-spotted sea squirt, white-spot ascidian, and white-spotted ascidian, is a species of tunicate, in the genus Pycnoclavella. Like all ascidians, these sessile animals are filter feeders.
Rhopalaea is a genus of tunicates belonging to the family Diazonidae. The genus has a cosmopolitan distribution in warm and temperate oceans.
Molgulidae is a family of tunicates in the class Ascidiacea. Following a revision in 2007, the family Hexacrobylidae was synonymized with Molgulidae.
Diazona is a genus of tunicates in the family Diazonidae.
Asajirus is a genus of marine tunicates. Asajirus indicus was found on the Antarctic Peninsula, west of Palmer Archipelago at a depth of 2763-2818m.
Oligotrema is a genus of marine tunicates.
Polyandrocarpa is a genus of ascidian tunicates within the family Styelidae.
Stolonica is a genus of ascidian tunicates in the family Styelidae.
Gamaster is a genus of ascidian tunicates in the family Molgulidae.
Minipera is a genus of ascidian tunicates in the family Molgulidae.
Protomolgula is a genus of ascidian tunicates in the family Molgulidae.
Rhizomolgula is a genus of ascidian tunicates in the family Molgulidae.
Bathypyura is a genus of ascidian tunicates in the family Pyuridae.
Bolteniopsis is a genus of ascidian tunicates in the family Pyuridae.