Intraspecific and Interspecific Variation in the Cryptotis nigrescens Species Complex of Small-Eared Shrews (Insectivora: Soricidae), with the Description of a New Species from Colombia Neal Woodman and Robert M. Timm Abstract The Cryptotis nigrescens species complex of small-eared shrews previously was considered to consist of a single, wide-ranging species with three subspecies distributed from southern Mexico to Panama. Our study of the patterns of morphological variation within this complex indicates that it is much more diverse and speciose than earlier believed. The group includes populations that occur only at high elevations (> 500 m) as well as the only taxon in the genus restricted to elevations below 100 m. Based on our investigations, we recognize five species: C. mayensis occurs on the Yucatan Peninsula and is known from an isolated locality in Guerrero; C. merriami has a patchy distribution from Chiapas, Mexico, to northern Costa Rica; C. nigrescens inhabits conterminous highlands in Costa Rica and Panama; C. mera is known from two isolated mountaintops along the Panama/Colombia border; and we describe a new species from the Central Cordillera of Colombia, which extends the known distribution of the complex to the southeast. In addition, recent studies indicate that C. hondurensis and C. magna may be imbedded phylogenetically within the C. nigrescens complex. Resumen Cryptotis nigrescens es un complejo de especies que solia considerarse como una sola especie con tres subespecies distribuidas a lo largo de America Latina desde el sur de Mexico hasta Panama. Nuestro estudio de patrones de variacion morfologica en este complejo indica que es diverso y con mas especies de las que se habia pensado antes. El grupo incluye poblaciones que habitan solamente en elevaciones por encima de los 500 m, y tambien el unico taxon en el genero que esta restringido a elevaciones bajo 100 m. Basados en nuestras investigaciones, reconocemos cinco especies. La primera, C. mayensis, se encuentra en la Peninsula de Yucatan y en una localidad aislada en Guerrero, Mexico. La segunda, C. merriami, tiene una distribucion discontinua desde Chiapas en Mexico hasta el norte de Costa Rica. La especie C. nigrescens habita en las cordilleras de Costa Rica y Panama. Se sabe que C. mera vive en las cimas de dos montanas aisladas en la frontera entre Panama y Colombia. La ultima es una especie nueva que describimos en esta publication y que mora en la Cordillera Central de Colombia y que extiende la distribucion del complejo hacia el sureste. Ademas, estudios recientes indican que las especies C. hondurensis y C. magna pueden estar relacionadas filogeneticamente con el complejo C. nigrescens. Introduction America. The genus reaches its greatest diversity in Mexico and Central America. Hall and Kelson Small-eared shrews of the genus Cryptotis have (1959) recorded 25 species of Cryptotis in this re-a wide distribution, occurring in parts of North gion. In his revision of the Middle American Cryp-America, Central America, and northwestern South totis, Choate (1970) recognized eight species of FIELDIANA: ZOOLOGY, N.S., NO. 74, SEPTEMBER 30, 1993, PP. 1-30 1
Intraspecific and Interspecific Variation in the Cryptotis nigrescens Species Complex of Small-Eared Shrews (Insectivora: Soricidae), with the Description of a New Species from Colombia
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