Conservation genetics of two narrow endemics: The Modoc sucker (Catostomus microps) and Kearney's bluestar (Amsonia kearneyana)

The field of conservation genetics has exploded in the past decade due to the increasing ease of generating genetic data and because there are important species management issues for which genetic data are indispensable. Resolving taxonomic uncertainties, diagnosing suspected hybridization, establishing genealogically based management units and minimizing inbreeding are all among the great successes in the field of conservation genetics. In the following studies, we utilize genetic approaches to provide conservation and management information for the Modoc sucker (Catostomus microps) and Kearney's bluestar (Amsonia kearneyana).In the management of rare and endangered species, there is often the need for information on population structure and levels of genetic variability. While microsatellites have emerged as an effective tool for this type of analysis, library development is often cost prohibitive. We demonstrate the feasibility of minimizing initial development costs by constructing hybrid libraries with equal proportions of DNA from two species and recovering equivalent numbers of microsatellites for each species.Kearney's bluestar, is a federally listed endangered plant that occurs in a number of small, isolated populations in the Baboquivari Mountains, Arizona. The taxonomy of the genus Amsonia (Apocynaceae) has been extensively revised, and in this study we evaluate the taxonomic status of Kearney's bluestar relative to other southwestern species using AFLP analysis. Our results support the retention of species designation for Kearneys bluestar and suggest the additional revision of the subgeneric classification of Amsonia.The Modoc sucker occurs in a small number of streams in the upper Pit River and Goose Lake basins on the Modoc Plateau in northeastern California, and is sympatric with the closely related Sacramento sucker (Catostomus occidentalis). This sympatry combined with the apparent presence of morphological intermediates has led some to conclude that the two species are hybridizing. We developed six species-specific AFLP markers, and examined suckers from across the Pit River system for evidence of hybridization. Modoc and Sacramento suckers co-occur in streams, and our data clearly indicate that they can hybridize with evidence of bi-directional introgression. Our data also indicate the reproductive isolation of certain populations of the two species, and little evidence of active hybridization...