Abnormal Starfish, Pentaceraster regulus from Thondi, East Coast of India

Abstract

Starfish Pentaceraster regulus was collected from Thondi coast, this species usually have 5 arms. An unusual, abnormal sea star, P. regulus was found with only 4 arms. Then it was length, weight arm's length were measured and tabulated.

Population size structure and abnormalities in the number of rays of the Sea Star Pentaceraster cumingi (Valvatida: Oreasteridae) in Bahía Chamela, Mexican Pacific

“…Arm number abnormalities are relatively common in the family Oreasteridae. Other studies have reported similar conditions for the congener P. regulus, a common starfish from the Western Central Pacific (James, 1999;Shanker & Vijayanand, 2014), P. linckii, widely distributed in the Indian Ocean (James, 1999;Chelladurai et al, 2015;Chelladurai & Doss, 2016), and P. nodosus, from the Indo-Pacific region (Chim & Tan, 2012). Abnormal arm number have been attributed to several causes like injury, regeneration errors, malnutrition, congenital issues, or damages in the metamorphosis process (Moore, 1974;Hotchkiss, 1979;Watts, Scheibling, Marsh, & McClintock, 1983).…”

“…columbiae Gray, 1840 (Fisher, 1945), Nardoa galatheae (Lütken, 1864) (James, 1999), Pentaceraster regulus (Müller & Troschel, 1842) (James, 1999;Shanker & Vijayanand, 2014), Pisaster ochraceus (Brandt, 1835) (Fisher, 1945), and Protoreaster linckii (Blainville, 1830) (James, 1999;Chelladurai, Balakrishnan, Jayanthi, Ajeesh-Kumar, & Mohanraj, 2015;Chelladurai & Doss, 2016). Other species where abnormal ray numbers have been recorded include Protoreaster nodosus (Linnaeus, 1758), a starfish widely distributed in the Indo-Pacific region (Chim & Tan, 2012) and Archaster angulatus Müller & Troschel, 1842 from the Indian Ocean and western Pacific (Keesing, 2017).…”

Report on the occurrence of abnormal four-armed red-knobbed starfish Protoreaster linckii (Echinodermata: Astroidea), Tuticorin coast, south-east coast of India

“…The wound can be healed by a regeneration of the arms or by just covering the wound by the growth of a body wall (Hotchkiss, 1979). At the time of the regeneration of the arms, the sea star may regenerate two arms instead of one or it may just close the wound without growing an additional arm (Shanker & Vijayanand, 2014). They are considered as an indicator of fishing intensity and biomarkers for pollution because of their important role in ecology.…”