Haliotis unilateralis Lamarck, 1822
Distribution: Red Sea, East Africa.

Uncommon and much sought after. Flat. Often with buttons in spiral arrangement.
12-14m deep, Eilat, Aqaba Gulf, northern Red Sea. 25mm. Original pictures © F. Frydman.

Lamarck's description:

H. testâ ovali, convexo-depressâ, rudi, subverrucosâ, albido-flavescente, maculis fuscis pictâ ;
labio elevato, anteriùs latere producto ; spirâ prominulâ, obtusâ.
An.
Rumph. Mus. t.40 fig. G? H?


Rumphii 40th plate, to which Lamarck refers ("An. Rumph. Mus. t.40 fig. G? H?").

The fig. G & H. show a small abalone, maybe a glabra.
The use of question marks after letters G & H shows the drawn animal is not the right one,
but something close in size and shape to the one Lamarck is talking about.
Source: Göttinger Digitalisierungszentrum.

"Habite les mers de Timor et de la Nouvelle-Hollande.
Bord droit fort court ; nacre peu brillante.
Diamètre longit., 16 lignes ; transv., 11 lignes et demie."

(Hist. Nat. des animaux sans vertèbres. T. III, p.513)


Attempt of translation in modern language:

Shell oval, flattened, rough, somewhat verrucous, of a pale yellow with dark blotches.
Exhausted margin, anterior end elongated; spire slightly prominent, apical area blunt.


Inhabits Timor, New-Holland.
Right side very short; nacre dull.
Size: 36 x 25 (mm) / 0,14 x 0,1 (inch).


This decription can concern many species:
some small ovina, some forms of varia a bit like this one:



Of a pale yellow, with dark blotches (but without warts).
Found at 5m deep, on smooth roundish volcanic rocks, north Bali. 32mm.
OK, I'm kidding. Original picture © R. Kershaw.
A smoother shell, very subverrucosus. Notice the plicate carina that follows the row of holes.
This feature is unique in Haliotidae.
6m deep, under stones, Dahab, Sinai. 27,5mm.
Original pictures © F. Frydman.
Spire visible in ventral view. Shallow water, under stones, Eilat.
23mm. Original pictures © F. Frydman.
Eilat again. 28mm. Original pictures © F. Frydman.
Specimen from SW. Indian Ocean.
8-15m by dive, Nacala Bay, Nampula, North Mozambique. 24,5mm.
Original picture © F. Frydman.
A collection from Mauritius. 13,5-27mm.
Original pictures © F. Frydman.

All pics © Olivier Caro