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ALECTROENAS(?) RODERICANA(MILNE-EDWARDS).
- Columba rodericana Milne-Edwards, Ann. Sc. Nat. (5) XIX art. 3, p. 16, pl. 12, ff. 1, 1a, 1b, 1c (1874).
The original description of the sternum is as follows:—"It belongs to a species small in size, barely as large as T. tympanistria, but evidently much better built for flight. In fact the most striking characters of this sternum are the large size of the bouclier, the large size of the lateral notches, and the shape of the keel, whose anterior angle is not much produced in front. The coracoidal grooves are large and only slightly oblique. The lateral branches detach themselves from the bone in front of the costal facets—they are very widely spread, and stretch more directly outwards than in the remainder of the species of the family. The lower lateral branches are equally divergent, and the median blade of the posterior edge is remarkable from its enlargement. The keel is moderately prominent, its anterior angle is much rounded, and does not reach the level of the episternal apophysis, as is the case, as a rule, in the pigeons. All these peculiarities, to which must be added the general flattening of the bone which is hardly at all sloped like a roof, separate the pigeon of Rodriguez very widely, not only from Erythroena and Turtur, but also from Vinago. In its shape in general, by the little pronounced keel and the direction of the latter, this sternum presents certain analogies to the essentially arboreal species such as those of the genus Carpophaga, but they all differ in having the space for the costal facets on the sides of the sternum much more extended, the superior lateral branches larger, and the latter arising further back, so that the lateral notches are smaller. Up to the present I do not know any genus of the family of Columbidae in which the sternum can at all be likened to that found recently in Rodriguez, and therefore in all probability this fossil remainder is of yet another vanished species, which I propose to call Columba rodericana." (Translated.)
It is probable that Milne-Edwards's C. rodericana belonged to the genus Alectroenas, and was the representative on Rodriguez of the Alectroenas nitidissima of Mauritius. 1 humerus in the Tring Museum.
Habitat: Rodriguez.
