Growing up to 92 cm (36 in) across, this ray has a lozenge-shaped pectoral fin disc about twice as wide as long, colored brown to gray above with many small, light spots.

This species can be identified by its tail, which is about as long as the snout-to-vent distance, lacks fins, and bears nine to twelve each of alternating black and white bands.

This species gives birth to live young; the developing embryos are nourished first by yolk and later by histotroph ("uterine milk") supplied by its mother.

The longtail butterfly ray was originally described as Raja poecilura by English zoologist George Shaw, in his 1804 General Zoology or Systematic Natural History.

He did not designate a type specimen as his account was based on an illustration by Scottish naturalist Patrick Russell, published a year earlier in Descriptions and Figures of Two Hundred Fishes Collected at Vizagapatam on the Coast of Coromandel.

[7] The pectoral fin disc of the longtail butterfly ray has the lozenge shape characteristic of its family, measuring around twice as wide as long.

The large mouth forms a transverse curve and contains over 50 tooth rows in each jaw, increasing in number with age; the teeth are small, narrow, and pointed.

[1] The most widespread member of its family in the Indo-Pacific, the longtail butterfly ray is found from the Red Sea and Somalia, westward across India and Sri Lanka, to China and southern Japan, the Philippines, and the western islands of Indonesia (including Borneo, Sumatra, and Java).

[10][14] The longtail butterfly ray is widely caught for meat and as bycatch in artisanal and commercial fisheries, including in India, Thailand, and Indonesia.

Though specific population and catch data are lacking, the longtail butterfly ray is thought to be susceptible to overfishing due to its low reproductive rate and the fact that pregnant females often abort their young when captured.