Chaenopsidae

Hastings, Philip A. & Springer, Victor G., 2009, Recognizing diversity in blennioid fish nomenclature (Teleostei: Blennioidei), Zootaxa 2120, pp. 3-14 : 8

Chaenopsidae

9) Stathmonotus . Stathmonotus stahli (Evermann & Marsh), was described based on specimens collected in Puerto Rico. Subsequently Stathmonotus tekla Nichols was described from Sand Key, Florida. Springer (1955) considered them subspecies and Hastings & Springer (1994) reported that they differ in number of segmented caudal-fin rays (11-13, modally 12 in stahli versus 10-12, modally 11 in tekla ), number of dorsalfin spines (41-45, modally 43 in stahli versus 39-44, modally 42 in tekla ) and number of precaudal vertebrae (17-19, modally 18 in stahli versus 16-19, modally 17 in tekla ). These features reliably distinguish the forms and we consider them both as valid species.

10) Chaenopsis . Chaenopsis alepidota (Gilbert) was described based on specimens from the northern Gulf of California collected aboard the Albatross. Subsequently Chaenopsis alepidota californiensis Böhlke was described based on three specimens collected from Isla Catalina off the coast of southern California. The latter subspecies was recognized based primarily on its having more rays in the dorsal and anal fins (total for all elements 95-97, mean = 96 versus 89-94, mean = 91.3), although Böhlke concluded that it “seems that little differentiation has taken place” ( Böhlke, 1957, p. 97). These meristic characters follow the expected patterns of phenotypic variation as a consequence of the significantly colder environmental temperatures experienced by the populations in California. As noted by Böhlke (1957), populations of species from colder areas generally have more fin-ray elements (Jordan’s rule; Jordan, 1891; Lindsey, 1988) calling into question the significance of the diagnostic features of these forms of C. alepidota . A recent study on their genetics ( Bernardi et al., 2003) found that the two forms are reciprocally monophyletic (albeit based on relatively small sample sizes), but also found evidence of recent gene flow among them. In addition, the percent sequence divergence in the mitochondrial control region between California and Gulf populations is low (1.87%) compared to disjunct sister species with similar distributions ( Dawson et al., 2006). In the absence of additional morphological data and analysis of genetic variation across their distributions, we do not recommend elevation of the population from California to species status.