Abstract
We document the occurrence of a natural hybrid between the Eastern Mudminnow, Umbra pygmaea (DeKay 1842) and the Central Mudminnow, U. limi (Kirtland 1840). Hybrid individuals were collected in a supratidal pool in a fresh-tidal marsh in the Hudson River, New York. ANOVA, ANCOVA, principal components analysis, and discriminant function analysis of meristics and morphometrics showed that the hybrids were distinguishable from the parental species and were generally intermediate between them. The tidal Hudson River is the only place these species are sympatric, and hybridization must have occurred within the last several decades. We designate neotypes for Umbra pygmaea and Umbra limi.References
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