Malleus regulus (Forskål, 1775)

Raines, Bret & Huber, Markus, 2012, 3217, Zootaxa 3217, pp. 1-106 : 24

Malleus regulus (Forsskål in Niebuhr, 1775)

Figures 10 H–K

Ostrea regula Forsskål in Niebuhr, 1775: p. 124.

Ostrea regula Forsskål, 1775 — Yaron et al., 1986: p. 183, figs. 26–27.

Malleus maculosus Reeve, 1858a : sp. 9, pl. 3, fig. 9.

Malleus maculosus Reeve, 1858 — Tröndlé & Boutet, 2009: p. 5.

Malleus (Malvufundus) maculosus (Reeve, 1858) — Rehder, 1980: p. 108, pl. 14, figs. 10–13.

Malvufundus regula ( Forsskål, 1775) — Oliver, 1992: p. 65, pl. 10, figs. 3 A–C.

Malleus regulus (Forsskål in Niebuhr, 1775)— Huber, 2010: p. 174, figs. 2–3; Severns, 2011: p. 446, pl. 203, fig. 6.

Material examined. Several articulated specimens and more than two dozen single valves (3.2 to 23.1 mm) from EI (BK), plus specimens from the Hawaiian and Marquesas Islands ( MHU), Saipan (BK), Kwajalein Atoll (BK)and Pitcairn Island (BK).

Diagnosis. “Shell generally small, but occasionally reaching a length of 35 mm, very irregular in growth form, main part of shell broadly ovate, anterior wing above byssal sinus short or absent, ventrally irregularly prolonged to varying length; early part of shell externally sculptured with irregular concentric lamellae, prolongation irregularly rugose and often showing blister-like laminations; color whitish often with irregular reddish purple maculations. Internally the main nacreous part of shell is sharply delimited from the ventral extension by its margin which may be strongly raised; the left valve is usually more deeply cupped than the RV, and both valves are whitish or golden in color, occasionally infused in places with purplish red; the shelly prolongation often shows a subcentral pallial ridge running partway down the prolongation.” ( Rehder 1980: 108, of M. maculosus Reeve, 1858 .)

Remarks. Rehder's diagnosis of this highly polymorphic species is one of the best ever reviewed and has been included.

Without genetic data a distinct Polynesian/Easter Island species cannot be substantiated. Morphologically there are no obvious differences to the Pan-pacific M. regulus .

Habitat. Commonly found at many locations around EI, in sand, from 0–80 m.

Distribution. Malleus regulus was originally described from the Suez, Red Sea, but is widely distributed throughout the Indo-Pacific, introduced into the Mediterranean, and is also known from eastern Africa, the Philippines, Micronesia, Marquesas Islands, Tuamotu Archipelago, Gambier Islands, Australia, Easter islands, the Hawaiian Islands and from the Panamic area (Coan, pers. comm., 2010). However, it is unreported from New Zealand or the Kermadec Islands— E6.