Astartila

Astartila transversa, from Dana 1849.


Belongs within: Bivalvia.

Astartila is a genus of burrowing bivalves known from the Late Permian of Australia (Cox et al. 1969).

Characters (from Cox et al. 1969): Small, ovate shells with gently convex posterior umbonal slopes and low, forwardly directed beaks; ornament varying from regular imbricate growth lamellae to irregularly spaced concentric threads; radial ornament of low, wide costae may be present: shell surface covered with radial rows of minute papillae; ligament external and opisthodetic, attached behind well-developed nymphs set in narrow escutcheon; lunule usually absent; right valve with single upright tooth derived from fold in valve margin; left valve with deep to shallow socket of type found in Megadesmus specimens with well-developed radial ornament having weakly developed megadesmid dentition; adductor scars subequal, the anterior smaller and deeper, commonly having several lobes on the posterior-dorsal edge; a single, deep, oval pedal scar occurring above anterior adductor and a large pedal retractor scar attached to upper edge of posterior adductor; a third pedal scar on rear side of umbonal cavity; pallial line simple and radially striate.

<==Astartila F71
    |--A. centralis Fletcher 1929 F71
    |--A. compressa Fletcher 1929 F71
    |--A. corpulenta Dan 1849 F71
    |--A. cyprina Dana 1849 F71
    |--A. danai F71
    |--A. intrepida Dana 1849 (see below for synonymy) F71
    |--A. obliqua Fletcher 1929 F71
    |--A. ovata Fletcher 1929 F71
    |--A. polita Dana 1849 F71
    |--A. pusilla (M’Coy 1847) [=Pachydomus pusillus] F71
    |--A. quadrata Fletcher 1929 F71
    |--A. subgemma Fletcher 1929 F71
    `--A. transversa Dana 1849 F71

Astartila intrepida Dana 1849 [incl. A. cyclas Dana 1849, A. cytherea Dana 1849, Pachydomus ovalis M’Coy 1847 (preoc.)] F71

*Type species of generic name indicated

REFERENCES

Cox, L. R., N. D. Newell et al. 1969. Treatise on Invertebrate Paleontology pt N. Bivalvia vol. 2. The Geological Society of America, Inc. and The University of Kansas.

[F71] Fletcher, H. O. 1971. Catalogue of type specimens of fossils in the Australian Museum, Sydney. Australian Museum Memoir 13: 1-167.

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