Meeting Abstract

P1.141  Jan. 4  Banana slug clades and proposed taxonomy. PEARSE, J.S.**; LEONARD, J.L.; BREUGELMANS, K.; BACKELJAU, T.; Univ. of California. Santa Cruz; Univ. of California. Santa Cruz; Royal Belgian Inst. of Natural Sciences, Brussels; Royal Belgian Inst. of Natural Sciences, Brussels pearse@biology.ucsc.edu

The genus Ariolimax Mörch, 1860 is currently broken into 5 taxa in 2 subgenera based on penis morphology. In A. Ariolimax, sensu stricto, A. (A.) columbianus columbianus (Gould, 1851) ranges from central California to southeast Alaska while A. (A.) c. stramineus Hemphill, 1891 is found on the coast of south-central California. In A. Meadarion Pilsbry, 1948. A. (M.) dolichophallus Mead, 1943, A. (M.) californicus californicus Cooper, 1872, and A. (M.) c. brachyphallus Mead 1943 are known from different parts of the San Francisco Peninsula. Our sequence data from 3 mitochondrial and 2 nuclear genes reveal an unresolved polytomy of 5 distinct clades---but not the original 5. There are 2 clades within A. (A.) c. columbianus, for which we propose species rank: A. columbianus ranging from northwest California to southeast Alaska and A. buttoni (Pilsbry and Vanatta, 1896) in north-central California. A. stramineus forms a third species-clade, and a fourth distinct clade is an undescribed species on Mount Palomar, San Diego County, California. The fifth clade (Meadarion) comprises at least 4 subclades, 3 already named as species or subspecies. We propose treating each as a species distinguished by morphology and sexual behavior: A. californicus and A. dolichophallus are found mainly in San Mateo and Santa Cruz counties, respectively, while A. brachyphallus has a disjunct distribution on the northern tip of the San Francisco Peninsula, the Monterey Peninsula in Monterey County, and Cambria in San Luis Obispo County. A fourth subclade corresponds to an undescribed species found on Fremont Peak, San Benito County. More in-depth analyses are needed to resolve the relationship among these 8 species, and whether the subgenus Ariolimax is paraphyletic with respect to Meadarion.