Palliolum Monterosato, 1884

Dijkstra, Henk H. & Beu, Alan G., 2018, Living Scallops of Australia and Adjacent Waters (Mollusca: Bivalvia: Pectinoidea: Propeamussiidae, Cyclochlamydidae and Pectinidae), Records of the Australian Museum (Rec. Aust. Mus.) 70 (2), pp. 113-330 : 170

Palliolum Monterosato, 1884

Palliolum Monterosato, 1884: 5 . Type species (by subsequent designation, Crosse, 1885): Pecten incomparabilis Risso, 1826 ; Recent, Mediterranean and adjacent E Atlantic.

Diagnosis. Palliolini with prominent antimarginal microsculpture, radial macrosculpture almost absent, no shagreen microsculpture or commarginal macrosculpture, foliated calcite (uniformly oriented laths) outside pallial line, byssal notch and sinus shallow throughout ontogeny, a weak ctenolium with closely spaced teeth, and few, weakly developed hinge teeth.

Distribution. Paleocene–Recent ( Waller, 2007: 17). Boreal Atlantic ( Waller, 1991: 35) and southwestern Pacific, littoral to bathyal.

Discussion. So far the present species is the only living species of Palliolum from the Indo-West Pacific region. Representative genera of Palliolini, mainly fossil, were enumerated by Beu (1995) and Beu & Darragh (2001) from New Zealand and southern Australia, but Waller (2006a: 20) transferred all these to his new tribe Mesopeplini .

For phylogeny and stratigraphy see Waller (1991: 35; 1993: 198; 2006a: 17–21), Waller & Marincovich (1992: 219), Beu (1995: 19) and Beu & Darragh (2001: 154).

For comparison with Delectopecten see Dijkstra & Southgate (2000: 14).

Figure 26. Distribution of Palliolum minutulum Dijkstra & Southgate (circles) and Pseudamussium challengeri (Smith) (stars).