Echinometra subangularis Desmoulins—Agassiz 1872: 234.
See: Mortensen (1943a: 357–368, figs. 172–175, pl. 41, figs. 1–5, pl. 42, figs. 12–14, pl. 43, figs. 1–13, pl. 44, fig. 9, pl. 64, figs. 17, 20–24); Pawson (1978: 20–23, figs. 8–10).
Occurrence: Atlantic, from North Carolina and Bermuda, southwards to Brazil (Mortensen 1943 a, Schultz 2006), and eastwards from Cape Verde to Angola (H.L. Clark 1925, Mortensen 1936); the subspecies E. lucunter polypora is restricted to Ascension and St. Helena islands (Pawson 1978).
Depth: 0–45 m (Mortensen 1943a).
Habitat: hard substrates (bioeroder; Mortensen 1943a).
Larval stage: planktotrophic (Mortensen 1921).
Fossil record: Ericichnus bromleyi, a relatively recent described ichnospecies portraying groove-borings found in a Pliocene fossiliferous outcrop in Malbusca (Santa Maria Island) is thought to be made by the sea urchin Echinometra lucunter (see Santos et al. 2015).
Commercial value: edible (Lawrence 2007).
Remarks: Agassiz (1872) listed the Azores under the geographical range of Echinometra lucunter (under the name Echinometra subangularis), which is clearly a misprint. The author never mentioned the archipelago again, whether listing the examined specimens’ locations or discussing the distribution range for this species. This tropical species does not occur in the present-day shallow waters of the Azores and no specimens were ever reported from the area.