Taxonomic novelties in Amaryllidaceae from the Department of Ancash, Peru, and a new combination in Clinanthus

Abstract Clinanthus inflatus (Amaryllidaceae) and Ismene parviflora are described from Ancash Department in Peru. The flower of C. inflatus is urceolate, and resembles that of Urceolina (Amaryllidaceae tr. Eucharideae), a unique morphology for the genus. Ismene parviflora, with its small, loosely formed, narrowly funnelform-tubular perigone with a ventricose limb, appears to have some affinity to subgen. Pseudostenomesson and may represent an intermediate form between the former and species of subgen. Ismene. Stenomesson rubrum is transferred to Clinanthus as C. ruber on the basis of its narrowly lorate leaf morphology.

Clinanthus Herb. was segregated from Stenomesson Herb. by Meerow et al. (2000), who demonstrated with nrDNA ITS sequences that the latter was polyphyletic. There are 15-20 species in the genus, which has never been monographed (León et al. 2006;unpubl. herbarium data). Peru is its center of diversity, and the genus occurs from southern Ecuador to northern Chile (Leiva and Meerow 2016). There are still novelties in the genus that await description (A. Meerow, pers. observ.). The genus is particularly diverse in northern Peru, and the complex orogeny of the Andes in Peru seems to have functioned as a species pump for the genus (Meerow 2010). The species are primarily found above 2000 m (León et al. 2006;unpubl. herbarium data), but several have colonized the Peru Current-cooled hills (lomas) of the Peruvian Pacific coast at much lower elevation (León et al. 2006;unpubl. herbarium data), in some cases occurring both there and in the Andes [e.g., C. coccineus (Ruiz & Pav.) Meerow]. One species, C. humilis (Herb.) Meerow, which retains the ovary inside the bulb until shortly before seed ripening (Herbert 1839; Baker 1871), reaches elevations above 4000 m (León et al. 2006;unpubl. herbarium data). Many are local endemics known only from the type localities (León et al. 2006). Photos and a specimen at USM sent to the first author for identification have been determined to represent an undescribed species in the genus, with unique floral morphology. We describe it here as Clinanthus inflatus. We also make a new combination in the genus Clinanthus for the species hitherto known as Stenomesson rubrum Herb. This species is transferred to Clinanthus based on its narrowly lorate leaf morphology.

Clinanthus inflatus
Distribution and ecology. Clinanthus inflatus is known only from the type locality (Fig. 3), in seasonally dry vegetation.
Phenology. Plants were collected in flower in March. Etymology. The specific epithet is from Latin and refers to the abruptly inflated perigone.

Preliminary conservation status.
Since nothing is known of the distribution of this species beyond the type locality, it is best to place it in the category Data Deficient (IUCN 2012(IUCN , 2017. The type specimen label indicates that it was abundant at the collection site. Notes. The urceolate perigone of C. inflatus is yet another example of the convergent evolution that characterizes the tetraploid Andean lineages (Meerow 2010 (Fig. 4B, D).

Ismene parviflora
Distribution and ecology. Ismene parviflora is known only from the type locality (Fig. 3), in seasonally dry vegetation.
Phenology. Plants were collected in flower in March. Etymology. The specific epithet is from Latin and refers to the small size of the flowers.
Preliminary conservation status. Since nothing is known of the distribution of this species beyond the type locality, it is best to place it in the category Data Deficient (IUCN 2012(IUCN , 2017. The type specimen label says it was abundant at the collection site. Notes. Ismene parviflora has greatest affinity morphologically to the two members of Ismene subgen. Pseudostenomesson (Velarde) Meerow, I. vargasii (Velarde) Gereau & Meerow and I. morrisonii (Vargas) Velarde, but the unique morphology of the new species make it difficult to assign I. parviflora to I. subgen. Pseudostenomesson with confidence at this time. Ravenna (1988) disagreed with the transfer by Velarde (1949) of Stenomesson morrisonii Vargas to Pseudostenomesson Velarde, but based on the same information (Vargas 1943), we believe it belongs with I. vargasii in I. subgen. Pseudostenomesson. In particular, the photo in Vargas (1943) shows the typical foliar morphology of Ismene, i.e. the aerial pseudostem formed by the tightly sheathing leaf bases. The two species of subgen. Pseudostenomesson are found in the Departments of Junin (I. vargasii) and Apurimac (I. morrisonii), and, unlike I. parviflora, have larger, fully infundibular, and completely green perigones.