Sunday, January 20, 2019

[Botany • 2018] Citharexylum peruvianum (Verbenaceae) • A New Species of Citharexylum from the Andean Foothills of Peru

Citharexylum peruvianum  N.O’Leary & Frost

in O'Leary & Frost, 2018. 

A new species of Citharexylum from the foothills of inter-Andean dry valleys in Peru, Citharexylum peruvianum, is described and illustrated herein. It is distinguished from other closely related species with caulinar spines (C. andinum, C. flexuosum, C. herrerae, C. montevidense, and C. weberbaueri), by inflorescence morphology, leaf size, and pubescence. The newly defined taxon has 15–40 flowered racemes, rachis 7–12 cm long, and coriaceous leaves, with the leaf blade being 4–6(8) × 2–3 cm and densely hirsute on the abaxial surface. A brief discussion on closely related species is provided. Citharexylum peruvianum is known exclusively from northwestern Peru, from the departments of Cajamarca, Lambayeque, and La Libertad. The species grows in the Andean foothills at mid-elevations between 1400 and 3000 m a. s. l., in rocky soils and on steep slopes with thorny scrubland. It is occasionally found in moist areas. This species has a restricted distribution and limited numbers of individuals, which will likely result in threatened status following formal review.

Fig. 2. Citharexylum peruvianum.
A–B. Habitat. C–D. Fruiting individuals. E. Fruiting raceme, large fruits plus one small bright orange fruit. F. Axillary racemes, recently fallen flowers, not congested, distanced. G. Spiny stem with flowering racemes. H. Flowering raceme. A, C, E from Frost and Tyson 99 (WTU); B, D from Frost and Tyson 121 (WTU); F, G, H from Frost and Tyson 100 (WTU).

Citharexylum peruvianum N.O’Leary & Frost, sp. nov.  

Etymology— The specific epithet refers to the species distribution in Peru, not having been found in other countries at the moment.

Nataly O'Leary and Laura Frost. 2018. A New Species of Citharexylum (Verbenaceae) from the Andean Foothills of Peru. Systematic Botany. 43(4); 1046-1051.  DOI: 10.1600/036364418X697733