Cassia virginis

Shrubs of unknown stature (probably 1+ rn), softly pilosulous throughout with fine erect gray hairs to ± 0.4-0.6 mm mixed with minute bulbous setules, the stems and lower face of the 2-foliolate lvs densely, the lustrous upper face thinly so, the small terminal leafy- bracteate panicle of racemes shortly exserted.

Stipules erect, subulate-setiform, 1.5-2.5 mm, early dry and deciduous.

Lvs strictly ascending along the stem and hence forwardly, but only loosely imbricated, 3-4.5 cm, very shortly petiolate, appearing sessile; petiole including the slightly swollen and discolored pulvinus 1.5-3 mm; lfts ascending from tip of petiole, turned half face to face on scarcely dilated pulvinule 0.4-0.9 mm, in outline broadly oblanceolate obtuse or minutely emarginate 2-4.2 x (0.6-)0.8-1.6 cm, at base shallowly cordate on proximal and rounded on distal side, the entire margin strongly revolute, the blades chartaceous, above impressed-venulose, beneath gray-pilosulous and dull, the straight subcentric midrib with ±8-12 secondary pairs and subsequent venules all sharply prominulous beneath, castaneous under the vesture, the venules of third and fourth order enclosing deeply recessed areoles much < 1 mm diam.

Racemes rather densely 12-30-fld, strictly ascending from axils of ±3-8 uppermost lvs to form a panicle of narrow, flat-topped outline, the 2-3 expanded fls standing at or above level of succeeding buds, the axis with short peduncle becoming 4-9 cm; bracts and bracteoles linear-subulate 0.9-3 mm, the latter situated 0.5-1 mm below calyx; pedicels narrowly ascending, subfiliform 5-7 mm; buds ovoid-acuminate, thinly pilosulous; sepals reddish, narrowly obovate- acuminate 7-7.5 x 2.5-3 mm; petals yellow, loosely ascending, 4 subsymmetrically spatulate- obovate, narrowed into a claw, 8-10 x 4-5.5 mm, the fifth falcately semi-obovate ± 10.5 mm, at middle incurved over androecium; ovary thinly pilosulous; ovules ± 7.

Pod and seed unknown. — Collection: 1.

Habitat not recorded, but to be expected on outcrops or along streams in the cerrado, probably not below 800 m, known only from the type-locality on the e. slope of Sa. do Espinhaço, upper Rio Jequetinonha basin, in n.-e. Minas Gerais. — Fl. III -IV.

A species instantly recognizable by the combination of subsessile bifoliolate leaves, broadly oblanceolate leaflets engraved-venulose ventrally and elaborately alveolate-reticulate dorsally, and short-pedicelled flowers arranged in a small, narrow, leafy-bracteate panicle. In texture, coloration, venation and vesture of gray pilose hairs mixed with minute bulbous setules C. virginis closely resembles C. adamantina, native also in the upper Jequetinonha valley, but this presumed ally has normally pinnate foliage and elongate pedicels. All other cassias at once approximately sympatric and bifoliolate have either truly sessile leaves, or plane-margined leaflets, or much simpler venation of the leaflet-blades. Similar reticulate venulation is found in C. auris-zerdae, but this allopatric species differs greatly in the broadly ovate, basally auriculate and amplexicaul (not oblanceolate) leaflets imbricated up a long wandlike stem. The type-collection of C. virginis consists of several terminal branchlets of what appears (by analogy) to have been a shrub a meter tall or more; but we have no field data on habit or habitat. We believe that C. virginis, like several other bifoliolate Absus cassias, has acquired the simplified leaf independently from pinnate antecedents.