Lathyrus pusillus Elliot

Echeverría, María L., Alonso, Sara I. & Comparatore, Viviana M., 2017, Survey of the vascular plants of Sierra Chica, the untouched area of the Paititi Natural Reserve (southeastern Tandilia mountain range, Buenos Aires province, Argentina), Check List 13 (6), pp. 1003-1036 : 1021

Lathyrus pusillus Elliot

Figure 21

Lathyrus pusillus Elliot (1823) : 223— Flora Argentina (2017); Tropicos

(2017).

Lathyrus crassipes Gillies , ex Hook. & Arn. (1830): 198— Cabrera

(1967): 609.

Therophytes, native with wide distribution in the American continent; previously recorded from Buenos Aires province but not from mountainous areas.

Characteristics. Annual twining herb, to 50 cm tall. A glabrous plant with short-winged stems. Leaves pinnately compond, with 2 linear leaflets and a terminal tendril, split into 1–3 segments; petiole 0.5–1.5 cm long, stipules sagittate. Inflorescence: racemes, with 1–3 flow- ers, with glabrous sepals and white to blue petals. Fruit: a linear and erect legume, turning brown at maturity.

Comments. This is an infrequent species in the study area. It grows in intermediate to full sunlight on slopes with moderately deep, moist soils. Lathyrus pusillus can be recognized from the many other Lathyrus species in the region by the presence of sagittate stipules and brown legumes that do not turn black when dry.