- Panolia eldii eldi: The Manipuri brow-antlered deer is found in Manipur, India. It is called sangai in Manipuri.
- P. e. thamin: The Burmese brow-antlered deer found in Myanmar, and westernmost Thailand.
- P. e. siamensis: The Thai brow-antlered deer is found in Cambodia, China, Laos, Thailand and Vietnam, and should perhaps be treated as a separate species. The population on the Chinese island of Hainan is sometimes considered another subspecies, P. e. hainanus, but this is not supported by genetic evidence. It was described by Lydekker in 1915.
The following measurements have been reported for the Eld's deer:
- Head–body length: 150–180 cm (59–71 in)
- Shoulder height: 110–125 cm (43–49 in)
- Tail length: 20–30 cm (8–12 in)
- Weight: 125–175 kg (276–386 lb)
- Antler length: 99 cm (39 in)
The deer are generally of medium size and are similar to the size and shape of the barasingha. The species has a very regal and graceful Cervus physique. Its legs are thin and long, and has a long body with a large head on a thin neck. The throat of a male has a thick mane of long hair. Males (stags) are taller and heavier than the females (hinds or does). Their coats, rough and coarse, change colour with the season; in summer the colour is reddish-brown, while in winter, it turns dark brown, with males tending to be darker than the females. The tail is short in length and the rump has no distinct patch. Despite these features, they are actually related to the Père David's deer. The antlers, bow- or lyre-shaped, do not grow upwards, but tend to grow outwards and then inwards; a smaller branch grows towards the front of the head. The brow tines are especially long and noticeable. The brow-antlered deer is so named because they have long brow tines. They shed their antlers every year, with the largest size attained during the breeding season.
Some observations on the habits of Eld's deer common to all three subspecies are a) active most of the time, seek shelter from the midday sun and migrate for short periods seeking water in the dry season and food in the growing season, b)seek areas that are seasonally burned in search of new grasses that grow after the burn, c) their diets comprise a variety of grasses, herbaceous plants, and shoots, grasses, fruit and wetland plants and they poach into cultivated crops to graze and browse in nearby fields of rice, lentils, maize, peas and grapes.
They are hunters' favourite game – as prized game – because of their impressive antlers and hides that are in demand in the local markets. They are widely hunted for food; they were believed to have been hunted to feed armies during many Asian wars. Their population has declined due to intense development activities necessitating reclamation of land for grazing, cultivation and fish farming, in all countries. In Burma, deforestion of the diperocarp forests is cited as a reason for the threat faced by the thamin deer. The habitat available for their protection is very limited; only 1% of the protected forests are suitable for its protection in South Asia. Even in protected areas, the animals are poached. Another striking problem is finding adequate funds and political will to protect the species. The species have a fragmented distribution and are therefore at risk from inbreeding and loss of genetic variation.