Article: A consideration of the tribe Thyrsoporelleae, dasyclad algae

The algal tribe Thyrsoporelleae Pia, 1927 (Family Dasycladaceae, Order Dasycladales) is examined in the light of later additions and discoveries. It is considered that the reasons for the earlier grouping are not now valid: Thyrsoporella, Belzungia, Dobunniella, and Placklesia now constitute the Thyrsoporelleae emend.; Dissocladella constitutes the Dissocladelleae trib. nov.; Trinocladus is transferred to the Triploporelleae. Possible ancestries are discussed, the limitations of the nature of this fossil evidence considered, and the extinction of all three reviewed against what is known and surmised of the decline of the post-Triassic Dasycladaceae generally.