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Colaptomena macallumi
Taxonomy
Rafinesquina expansa macallumi was named by Reed (1917) [Rafinesquina expansa (Sowerby), var. nov. Macallumi].
It was recombined as Macrocoelia macallumi by Williams (1962); it was recombined as Colaptomena macallumi by Candela and Harper (2014).
It was recombined as Macrocoelia macallumi by Williams (1962); it was recombined as Colaptomena macallumi by Candela and Harper (2014).
Synonymy list
| Year | Name and author |
|---|---|
| 1917 | Rafinesquina expansa macallumi Reed pp. 865 - 866 figs. Plate XI, figs. 17-20 |
| 1962 | Macrocoelia macallumi Williams p. 216 figs. Pl. XXI, figs. 19, 25, 28; P1. XXII, figs. 1, 2 |
| 2014 | Colaptomena macallumi Candela and Harper pp. Supplement 1 |
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If no rank is listed, the taxon is considered an unranked clade in modern classifications. Ranks may be repeated or presented in the wrong order because authors working on different parts of the classification may disagree about how to rank taxa.
†Colaptomena macallumi Reed 1917
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Diagnosis
| Reference | Diagnosis | |
|---|---|---|
| F. R. C. Reed 1917 | Shell subquadrate to semielliptical, concavo-convex, not flattened but much compressed; hinge-line equal to width of shell; cardinal angles rectangular or slightly obtuse; hinge-line not denticulate. Pedicle-valve very gently convex; beak small, pointed, scarcely rising above hinge-line; hinge-area narrow. Brachial valve slightly concave; beak inconspicuous; hinge-area narrower than in opposite valve. Interior imperfectly known ; muscle-scars very faint. Pedicle-valve with very weakly impressed flabellate diductor scars, about one-fourth to one-third length of valve. Surface of valve covered with 40-60 subequidistant regular straight filiform primary riblets of equal size and increasing in number by intercalation at about half their length and again nearer margin, with 3—7 much finer intermediate thread-like lines between them in interspaces ; whole surface of shell crossed by very delicate concentric striation. Substance of shell finely and densely punctate. | |
| A. Williams 1962 | Subquadrate Macrocoelia about three-quarters as long as wide, piano- to concavo-convex in lateral profile with the pedicle valve about one-sixth as high as long; ornamentation unequally parvicostellate with differentially thickened and raised costae and costellae defining narrow sectors, costellae closely spaced with a modal count of 6 per millimetre antero-medianly and cancellated by fine concentric lamellae; ventral muscle-scar flabellate, over two-fifths as long as the pedicle valve and rather wider than long, dental lamellae short, obtusely divergent; dorsal interior with parallel-sided or slightly wedge-shaped cardinal process lobes, covered apically by a convex chilidium, bearing 2 or 3 ridges on each posterior face, and divergent, being almost two-thirds as long as their combined width; sockets tuberculate, median ridge and flanking divergent septa variably developed, subperipheral rim well developed at about 26 mm. from the dorsal umbo. |