Catala's sea star (Thromidia catalai)

Classification (WoRMS)

Full classification as recorded by WoRMS: Kingdom: Animalia · Phylum: Echinodermata · Class: Asteroidea · Order: Valvatida · Family: Mithrodiidae · Genus: Thromidia.

Accepted name: Thromidia catalai · Authority: Pope & Rowe, 1977 · Taxonomic status: accepted · AphiaID: 367763.

Source: World Register of Marine Species (WoRMS) — https://www.marinespecies.org/aphia.php?p=taxdetails&id=367763 (CC BY 4.0). Accessed 2026-09-23.

Biology and life history (SeaLifeBase)

Measured values published by SeaLifeBase for Thromidia catalai. Only fields the database actually holds for this species are shown; these are database values, not aquarium guidance.

Depth range: 10–105 m · Habitat zone: benthic.

SeaLifeBase notes: Found in continental shelf; outside the reefs (Ref. 103185).

Source: SeaLifeBase species summary (SpecCode 138779) — https://www.sealifebase.se/summary/Thromidia-catalai.html (CC BY-NC 3.0 — non-commercial use only). Accessed 2026-09-23.

Distribution and occurrence records (GBIF)

68 georeferenced occurrence records for Thromidia catalai are published through GBIF from 17 countries or marine areas. The map above plots 41 distinct locations from a sample of 68 records, omitting 5 inland records that carry an institution's coordinates rather than a collection site; it shows where the species has been observed and reported, not a modelled range.

Most records by country or area: Philippines (22); South Africa (7); Indonesia (5); Malaysia (5); United States of America (5); Australia (4); Solomon Islands (4); Japan (3); New Caledonia (3); Papua New Guinea (3); Fiji (1); Micronesia (Federated States of) (1); United Kingdom of Great Britain and Northern Ireland (1); Guam (1); Marshall Islands (1).

Marine regions with a valid WoRMS distribution record: New Caledonian Exclusive Economic Zone; Hawaiian Islands.

Source: GBIF Occurrence Search (taxonKey 2272787) — https://www.gbif.org/occurrence/search?taxon_key=2272787&has_coordinate=true (records CC0 / CC BY); WoRMS distribution records (MarineRegions) — https://www.marinespecies.org/aphia.php?p=taxdetails&id=367763 (CC BY 4.0); Natural Earth 110m basemap — https://www.naturalearthdata.com/ (public domain). Accessed 2026-09-23.

Description and natural history (Wikipedia)

Thromidia catalai is a large starfish with five arms and a diameter of up to 70 cm, weighing up to 6 kg. The surface is covered with low tubercles, giving it a granular appearance. The arms are robust and cylindrical, not tapering much and having rounded tips. The disc is small, and both disc and arms are a pinkish-beige colour, apart from the tips of the arms, which are a dark orange-brown. In contrast to other members of the genus Thromidia, the tips of the arms have small, widely spaced tubercles. The only other starfish with which this species could be confused is the closely related Thromidia gigas, but that species, though a similar size, has paler arm tips and is only found in the southern Indian Ocean, around Madagascar, Réunion and South Africa.

Thromidia catalai is found in the tropical Indo-Pacific region, its range extending from Indonesia to Hawaii, and from southern Japan to New Caledonia and northern Australia. It is found typically in and between reefs in the places where detritus settles, at depths between about 15 and 130 m, but usually deeper than 30 m on the continental shelf. Although seldom encountered, this may be because of the considerable depth at which it lives rather than its rarity.

Little is known of the feeding habits of this starfish, but related species are carnivorous with a diet mainly consisting of molluscs and echinoderms. The starfish everts its stomach to blanket the prey, secretes enzymes and digests it. As with other starfishes, the sexes are separate and the eggs and sperm are liberated into the water column where fertilization takes place.

Source: Wikipedia: Thromidia catalai — https://en.wikipedia.org/wiki/Thromidia_catalai (CC BY-SA 4.0). Accessed 2026-09-23.

Gallery