Sesuvium trianthemoides, Correll

Bohley, Katharina, Winter, Pieter J. D. & Kadereit, Gudrun, 2017, Data from: A revision of Sesuvium (Aizoaceae, Sesuvioideae), Data in brief 48 (1), pp. 109071-109071 : 144

SESUVIUM TRIANTHEMOIDES Correll in Rhodora 68: 422. 1966.— TYPE: U. S. A., Texas: Kenedy County, dunes, 11 Jul 1947, Tharp 47431 (holotype: TEX!)

Slender procumbent to ascending, annual herb; stems pale and thin (diam ∼ 2.5 mm), roots relatively short; scattered large bladder cells on leaves and stems and fine white dots around the axils. Leaves oblanceolate, flat, lamina up to 20 mm long and 8 mm wide, with a distinct petiole, lateral flaps wide (∼ 2 mm). Flowers sessile, about 6 mm long, one pair of bracts at base; inconspicuous tepal teeth compared to other species of the genus. Stamens five. Ovary with 2 carpels and 2 styles. Fruit large and tapered capsules with broad bases, often exceeding the length of the tepals; styles rarely still attached to the ripe capsule, often only two short tips remain. Seeds up to 1.5 mm long, reniform, with a slightly structured seed coat, dull black, brown or grey.

Distribution and Habitat — The species appears to be strictly endemic in Texas, U. S. A ( Fig. 9). It grows on sandy soil, probably near rivers.

Vernacular Name — Texas sea purslane.

Representative specimens examined — U. S. A. Texas, Kenedy County: Dunes, 11 Jul 1947, Tharp 47431 (TEX); San Patricio County: 9.7 km from Sinton, sandy soil along Aransas River, 28 Jun 1954, F. B. Jones 964 (BRIT).

Notes — Only two specimens were seen, since no other material was available. It would be very desirable to increase the number of specimens in collections. There is a close resemblance between S. trianthemoides and S. maritimum , but due to distinctive morphological traits such as large and tapered capsules and the 2-carpelate ovary their status as separate species seems justified.