Thursday, July 21, 2011

[Botany • 2009] Impatiens cornutisepala S. X. Yu, Y. L. Chen & H. N. • new species (Balsaminaceae) from Guangxi, China

A new species from Guangxi Province, Impatiens cornutisepala S. X. Yu, Y. L. Chen & H. N. Qin, is described for the Balsaminaceae in China. It is similar to I. dicentra Franchet ex Hooker f. in the 1- flowered peduncle and the lobes of the lateral united petals that are terminated by a long filamentous bristle. However, the new species differs from the latter in its narrowly elliptic to oblanceolate leaf blade, the smaller lateral sepals with entire margins and a prominent green cornute appendage dorsally, the spur of the lower sepal that is entire at the tip, and its differing leaf epidermis micromorphology. The micromorphology of seeds and pollen under SEM is presented.

Key words: Balsaminaceae, China, Guangxi, Impatiens, IUCN Red List.

Impatiens cornutisepala S. X. Yu, Y. L. Chen & H. N. Qin, sp. nov.

TYPE: China. Guangxi: Quanzhou Co., Jiaojiang, in valley near river, 25u309490N, 110u559170E, ca. 1000–1300 m, 6 Oct. 2006, S. X. Yu 4023 (holotype, PE; isotype, IBK, MO). Figure 1.

Species ob pedunculum uniflorum et lobulos petalorum lateralium connatorum apice in trichomata longa desinentes Impatienti dicentrae Franchet ex Hooker f. similis, sed ab eafoliis anguste ellipticis vel obovato-ellipticis, sepalis lateralibus parvis margine integris dorsaliter appendicibus corniformibus viridibus praeditis atque calcari apice integro differt.

Distribution and ecology. Impatiens cornutisepala is endemic to northeastern Guangxi Province, China, recorded so far only from Quanzhou County. The plants were found in a moist valley in Jiaojiang village from 1000–1300 m elevation, in association with Pilea Lindley, Elatostema J. R. Forster & G. Forster, Carex L., an unidentified bamboo species, and other grasses.

IUCN Red List category. The population covers an area of about 1000 sq.m. and includes approximately 500 to 600 individuals. According to IUCN Red List criteria (IUCN, 2001), Impatiens cornutisepala should be categorized as Critically Endangered (CR).

Phenology. The new species was observed in flower from July to October and in fruit from August to November.

Etymology. The specific epithet cornutisepala is from the Latin and refers to the lateral sepals with their green cornute appendages.

Sheng-xiang Yu, Xiu-ren Zhou, and Yi-ling Chen. 2009. Impatiens cornutisepala (Balsaminaceae), a New Species from Guangxi, China. Novon: A Journal for Botanical Nomenclature. 19(4):562-566. DOI: 10.3417/2008008