ARENODOSARIA Finlay, 1939

 

 

Type species: Clavulina robusta Stache, 1864 (*3054), p. 169; = Clavulina antipodum Stache, 1864 (*3054), p. 167; OD.Arenodosaria Finlay, 1939 (*1127), p. 95.

Test short and stout, early stage of up to five chambers per whorl, rapidly becoming triserial, then with a reduced biserial stage and short uniserial stage, circular in section; wall coarsely agglutinated, canaliculate, with thin dense inner layer, finely agglutinated thick and dense median layer, and an outer coating of coarse grains; aperture a vertical straight to curved slit in the juvenile, later nearly terminal and central, varying from a curved slit to subradiate or cribrate. M. Eocene to M. Miocene; New Zealand; Andaman Sea: Car Nicobar.

 

Remarks: Cushman (1937, *783, p. 167) placed C. robusta in the synonymy of C. antipodum Stache, regarding the former as the microspheric generation and the latter as the megalospheric generation, although Finlay (1939, *1127) considered both species as recognizable, with distinct ranges. Their synon­ymy has been upheld by Hornibrook (1971, *1541, p. 32), who selected a lectotype for C. antipodum from Stache's original slides. Arenodosaria differs from Plectina in having a distinct early triserial stage, reduced biserial stage, and final stage of three to four uniserial chambers.