PLAKARTHRIUM AUSTRALIENSE, A THIRD SPECIES OF PLAKARTHRIIDAE (CRUSTACEA: ISOPODA)
The Plakarthriidae share with four genera of Sphaeromatidae a flat habitus and a marginal row of setae on antenna 1, coxae and uropods, modified to maintain contact with the substrate. They do not possess areas of scales on pleopod 5, a probable sphaeromatid synapomorphy. The possibility exists that...
Main Authors: | , |
---|---|
Other Authors: | |
Format: | Text |
Language: | English |
Subjects: | |
Online Access: | http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.565.1057 http://museumvictoria.com.au/pages/4126/58_2_poore.pdf |
Summary: | The Plakarthriidae share with four genera of Sphaeromatidae a flat habitus and a marginal row of setae on antenna 1, coxae and uropods, modified to maintain contact with the substrate. They do not possess areas of scales on pleopod 5, a probable sphaeromatid synapomorphy. The possibility exists that Plakarthriidae are a highly derived offshoot of a clade that also gave rise to the flattened “cassidiniine ” sphaeromatids. Plakarthrium australiense sp. nov. is described from the southern Australian marine shelf and compared with the only two other species of the genus and family. The new species differs from P. typicum from New Zealand and P. punctatissimum from subantarctic islands of the South Atlantic and Antarctic Peninsula in having pleonite 1 fully indicated dorsally, only pleonite 2 indicated laterally and pleotelson tapering to 80 % of its anterior width posteriorly. |
---|