Parapterois macrura

Lore & Background

Parapterois macrura was first formally described as Pterois macrura in 1896 by the English naturalist Alfred William Alcock, with the type locality given as the Malabar Coast off Calicut. The specific name macrura means 'large tail', an allusion to the filamentous extension of the upper caudal fin ray, which is as long as the body from the eye back.

This species generally grows to a length of 11 centimetres (4.3 in). It differs from its congener P. heterura in that P. macrura lacks scales in a pit between the posterior nostrils, while P. heterura has them (except for a population of P. heterura found off West India, South Africa, and Mozambique, which may be a different species). The two species do not differ much in fin spine, fin ray, gill raker counts, and most body proportions; their differences lie in a small difference in head proportions. In adults, the upper margin of the eye of P. heterura is below the base of the first dorsal fin spine, while it is above in P. macrura (this trait is not consistent in juveniles, in which the eye margin may be below in both species).

Parapterois macrura is found in the northwestern Indian Ocean in the Arabian Sea, recorded from the coast of Somalia, Oman, Pakistan and southwestern India. It occurs at depths between 64 and 130 m (210 and 427 ft), and its habitat preference is thought to be similar to that of P. heterura: sheltered coastal bays to deeper waters where there are fine sand or silt substrates.

Reader's Guide

Parapterois macrura is a species of scorpionfish known from the western Indian Ocean, first described in 1896 by Alfred William Alcock. Its notable feature is the filamentous extension of the upper caudal fin ray, which gives it the specific name macrura, meaning 'large tail'. The species reaches a length of 11 cm and is found at depths between 64 and 130 m in the Arabian Sea, with records from Somalia, Oman, Pakistan, and southwestern India. Its habitat is thought to be similar to that of P. heterura, favoring sheltered coastal bays to deeper waters with fine sand or silt substrates. The article notes taxonomic uncertainty regarding a population of P. heterura off West India, South Africa, and Mozambique, which may be a different species. The species is distinguished from P. heterura by the absence of scales in a pit between the posterior nostrils and by the position of the eye margin relative to the first dorsal fin spine in adults. These details contribute to the understanding of scorpionfish diversity in the Indian Ocean.

Did You Know?

• Parapterois macrura was originally described as Pterois macrura by Alfred William Alcock in 1896.
• Its specific name macrura means 'large tail', referring to a filamentous extension of the upper caudal fin ray as long as the body from the eye back.
• It differs from P. heterura in lacking scales in a pit between the posterior nostrils.