Menonvillea minima Rollins (1955: 52)

Salariato, Diego L., Zuloaga, Fernando O. & Al-Shehbaz, Ihsan A., 2014, A revision of the genus Menonvillea (Cremolobeae, Brassicaceae), Phytotaxa 162 (5), pp. 241-298 : 281

18. Menonvillea minima Rollins (1955: 52) . Type:— CHILE. [Región de Atacama]. Prov. Huasco, Huasco , September 1885, F . Philippi 1948 (lectotype here designated SGO 77941!; isolectotypes G!, SGO 77940!, probable isolectotype SGO 68272!) .

Annuals. Stems (1.5−)38(−10) cm, highly branched at base, usually irregularly winged, glabrous throughout. Leaves basal and cauline, sessile to subsessile; blade linear, trifid to deeply 3-lobed or entire, rarely subpinnately lobed or dentate, 1−3 cm × 1−3(−6) mm, attenuate to a petiole-like base, glabrous or with few, simple crisped trichomes to 0.3 mm long. Racemes terminal and axillary, densely flowered, ebracteate, corymbose, elongated in fruit, 2−4.5 cm long; rachis glabrous, straight, winged; fruiting pedicels divaricate, 5−8(−10) mm long, usually arcuate, glabrous, winged abaxially. Sepals oblong, 1.5−2.5 × 1.5−1.7 mm, glabrous, erect, not saccate at base, persistent at fruit maturity, margin membranous; petals creamy white, broadly obovate, 3−4 × (1.5−) 2−2.5 mm, base clawlike, glabrous, not papillate; stamens subequal in length; filaments free, neither dilated nor papillate at base, 1.7−2.5 mm long; anthers ovoid, 0.4−0.5(–0.6) mm long; nectar glands confluent, somewhat petaloid. Fruits globose, glabrous; valves hemispherical to slightly longer than broad, strongly convex dorsally, flat ventrally, 1.2– 1.5(−1.8) × 1−1.2(−1.4) mm, corky, verrucose to rugose or rarely smooth, with a conspicuous midvein dorsally, wingless or with rudimentary wings to 0.2 mm wide; gynophore to 0.5 mm long; style 1−1.5 mm long; stigma slightly 2-lobed. Seeds ovate, 0.8−1 × 0.6−0.7 mm, plump; cotyledons incumbent. Fig. 20 .

Distribution and habitat:— Menonvillea minima is endemic to Region III (Atacama) of Chile along the coastal areas of Huasco and Freirina provinces. It grows on sandy soils at elevations to 100 m ( Fig. 13H ).

Phenology: —Flowers between September and October.

Taxonomic notes:— Menonvillea minima is easily distinguished from other annual species of the genus by being small plants with conspicuously winged pedicels and hemispherical and wingless fruit valves. Menonvillea zuloagaensis , another species with wingless fruits, differs by its perennial habit, long-petiolate and palmately lobed (vs. sessile to subsessile and, deeply 3-lobed, entire or rarely subpinnately lobed) leaves and persistent (vs. caducous) sepals, petals and stamens.

Rollins (1955) cited type of M. minima as “Huasco, Sept 1885, F. Philippi 1948 ( SGO)” and an isotype from G. However, SGO has two sheets with the same locality data ( SGO 77941 and SGO 77940). Therefore, the sheet SGO 77941, which was annotated by Rollins in 1952 at the type, is designated herein as the lectotype .

Al-Shehbaz et al. (2011) designated SGO 63208 as an isolectotype of M. parvula Phil. , but its label reads “Huasco, Sep 1885, F. Philippi ” and suggests that the specimen belongs to the type collection of M. minima . The type of M. parvula is labeled as “Huasco, Oct 1866, F. Philippi ” ( Philippi, 1892; see M. parvula under synonymy of M. chilensis ).

Representative Specimens:— CHILE. III Atacama: Prov. Huasco, Com. Freirina, Playa de Carrizalillo , a 6 km del pueblo de Carrizalillo, 23 September 1941, Muñoz & Johnson 1990 ( SGO); Com. Huasco, Huasco, 19 September 1966, Montero 7619 ( CONC) .

Figures

FIGURE 13. Distribution of species of Menonvillea sect. Menonvillea. A, M. chilensis. B, M. constitutionis. C, M. filifolia. D, M. flexuosa. E, M. linearis. F. M. litoralis. G. M. marticorenae. H, M. minima. I, M. orbiculata. J, M. pinnatifida. K, M. purpurea.

FIGURE 20. Menonvillea minima Rollins. A, plant. B, flower. C, sepal. D, petal. E, stamens and ovary. F, nectar glands and ovary. G, fruit mericarp, dorsal view. H, fruit mericarp, ventral view. I, seed. J. embryo. From Behn s.n. (CONC 8986). Scale bars: A = 1 cm; B–J= 1 mm.