Menonvillea patagonica Spegazzini (1902: 229)

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 : 265-266

7. Menonvillea patagonica Spegazzini (1902: 229) . Type:— ARGENTINA. [Provincia de Chubut]. Arid areas between Teka-choique and Carrenleufú, 1899, N . Illín s.n. (holotype LP 10408 !) .

Menonvillea alyssoides Rollins (1955: 25) . Type:— ARGENTINA. [Provincia de Neuquén]. Zapala , 12 October 1925, H. F. Comber 66 (holotype K!; isotype E!) .

Annuals with conspicuous taproot. Stems 1.5−14 cm, 1 to several from base, erect to subdecumbent, branched above, sparsely hirsute with straight, simple, terete trichomes 0.4−0.6 mm long. Leaves basal and cauline, petiolate, basal not rosulate to subrosulate; blade broadly spatulate to oblong in outline, shallowly pinnately lobed to repand, 0.3−3 cm long, sparsely hirsute with antrorse, terete trichomes; cauline leaves reduced in size upward. Racemes terminal, rarely axillary, bracteate at least proximally, corymbose, elongated in fruit, 2−8 cm long; rachis straight, pilose to sparsely hirsute; fruiting pedicels divaricate, straight, 3−6 mm long, sparsely hirsute. Sepals oblong, 1.5−2 × ca. 1 mm, caducous, sparsely hirsute, erect, not saccate at base, margin membranous; petals white, spatulate, 1.5−3(–3.5) × 0.6−1(–1.5) mm, claw papillate; stamens slightly tetradynamous; filaments free, erect, dilated and papillate at base, 1−1.5(−1.8) mm long; anthers ovate, 0.3−0.6 mm long; nectar glands confluent, not petaloid. Fruits subglobose, glabrous; valves conspicuously convex adaxially, strongly concave abaxially, cupuliform to globose in cross section, 2-winged, (2.5−)3−5 × (2−) 3−4 mm, emarginate above and below; wings extending away from the replum or reflexed to form a nearly complete cavity, 0.4−1 mm wide, slightly undulate to straight; gynophore obsolete, to 0.25 mm long; style (0.8−) 1−1.5 mm long; stigma slightly decurrent. Seeds ovate, 1.5−1.7 × 1−1.3 mm, slightly compressed; cotyledons accumbent, often persistent.

Distribution and habitat:— Menonvillea patagonica is endemic to Argentina in Chubut, Neuquén and Río Negro provinces. It grows on sandy-rocky soils frequently close to streams at 500−2500 m ( Fig. 12G ).

Phenology:— Flowers from October to February.

Taxonomic notes:— Menonvillea patagonica is easily distinguished by its glabrous fruit valves, strongly concave abaxially and with wings extending away from the replum or curved to form a nearly complete cavity. Rollins (1955) differentiated M. alyssoides from M. patagonica mainly by having taller plants prominently branched at base, petals 2.5−3.5 (vs. ca. 1.5) mm long, and reflexed fruit wings often forming a cavity (vs. poorly developed wings not forming a cavity). However, specimens such as Boelcke 11235 (BAA, BAB, SI) have closed valves and petals less than 2.5 mm long, and Vallerini 396 (BAA, BAB) have open valves and petals more than 3 mm long. Additionally, the degree of wing curvature can vary from open to reflexed or closed on the same plant (e.g., Vallerini 396 at BAA). These observations, along with the unreliable stem branching, show that there are no clear morphological differences that justify the recognition of M. alyssoides as distinct from M. patagonica .

Representative Specimens:— ARGENTINA. Chubut: Depto. Languiñeo, Ruta 12 entre Gualjaina y Paso del Sapo, pasando el río Gualjaina , 31 October 2008, Biganzoli & Larsen 1907 ( SI) , Depto. Río Senguer, Ruta Nacional 40, Parador Estancia Laurita , 19 November 2012, Zuloaga et al. 13942 ( SI) . Neuquén: Depto. Catán Lil, Catán Lil , 14 December 1972, Valerini s.n. ( BAA, CRP 3521 ) ; Depto. Chos Malal, Chos Malal, cajón inferior del Arroyo turbio (localmente llamado arroyo Domuyo ), 28 January 1964, Boelcke 11306 ( BAA) , cajón del Arroyo del Cruce , en la ladera seca próxima al arroyo, 27 January 1964, Boelcke 11235 ( BAA, BAB, SI) ; Depto. Zapala , 15 km al sur de Zapala, 19 November 1969, Ancibor et al. s.n. ( BAB 90253, SI) . Río Negro: Depto. 25 de Mayo, aprox. 60 km al Sur de Jacobacci , arroyo Quetrequile , 9 November 1966, Abadie & Vallerini s.n. ( BAA, CRP 1048 ) ; Depto. Pilcaniyeu, RN 40, a aprox. 10 km al sur de Paso Flores, 29 November 1963, Vallerini 396 ( BAA, BAB) .

Figures

FIGURE 12. Distribution of species of Menonvillea sect. Cuneata. A, M. cicatricosa. B, M. comberi. C, M. cuneata. D, M. frigida. E, M. macrocarpa. F. M. nordenskjoeldii. G. M. patagonica. H, M. rigida. I, M. spathulata. J, M. virens.