On some colour patterns of the young Malay rusa (Cervus unicolor equinus). Records of the Raffles Museum, No. 9
This short note by F. N. Chasen, Keeper of the Raffles Museum, documents the colour-pattern of a pre-natal fawn of the Malay Rusa (Cervus unicolor equinus) and compares it with previously recorded variation in spotted and unspotted young of the species.
Summary
Chasen reviews earlier observations by Blanford, Lydekker, Ridley, and Hose, which agree that only the hind quarters of young peninsular Rusa are spotted, and that Bornean young may or may not be spotted depending on locality. He then describes a pre-natal fawn from a Johore adult female recently received by the Raffles Museum, which is “so well spotted that it seems to merit notice” (p. 90). In addition to spots on the rump and shoulders, this specimen shows a distinct longitudinal row of spots along each side of the spine, indistinct spotting on the nape, and faint spots on the flanks (p. 90). Chasen notes the pattern is essentially similar to that of the newly born Muntjac, differing chiefly in that the spots are comparatively larger, more distinct, and more numerous. A second fawn of unknown origin (hind-foot about 255 mm) is also briefly described, showing three conspicuous rump spots and faint lighter patches on the shoulders and hind-neck (p. 90). The article is accompanied by a plate (Plate II) illustrating the pre-natal fawn.