Freshwater Fish Zoogeography 
49 
particularly difficult to understand the absence of amblyopsids from the 
Marianna caves, considering that this area lies above the Cody Scarp, 
and thus should not have been affected by higher sea levels during the 
Pliocene. Since these fishes apparently did not reach the Marianna 
caves, it is even less likely that they ever reached those caves to the east. 
Mention should also be made of the absence of Florida troglobitic 
fishes of marine derivation. Two genera, comprising four species, of the 
otherwise exclusively marine family Bythitidae occur in fresh and brack- 
ish waters of caves in the Bahamas, Cuba and the Yucatan peninsula 
(Hubbs 1938; Cohen and Robins 1970; Burgess 1983a, b,c). Considering 
this, it is reasonable to think that species of this family might also occur 
in Florida caves. Various reasons for their absence could be advanced, 
involving a combination of geographical distance, opportunity, and tim- 
ing of evolutionary and geological events. For the moment, at least, 
there are no obvious answers to this question. 
ACKNOWLEDGMENTS.— I wish to thank S. David Webb and 
Gary S. Morgan, Florida State Museum, and Anthony F. Randazzo, 
Department of Geology, University of Florida, for their helpful advice 
and comments pertaining to Florida geology, and also for reading and 
commenting upon an earlier draft of this paper. 
LITERATURE CITED 
Alt, David. 1968. Pattern of post-Miocene eustatic fluctuation of sea level. 
Palaeogeogr. Palaeoclimatol. Palaeoecol. 5:87-94. 
, and H. K. Brooks. 1965. Age of Florida marine terraces. J. Geol. 
73:406-411. 
Bailey, Reeve M., and C. L. Hubbs. 1949. The black basses ( Micropterus ) of 
Florida with description of a new species. Occas. Pap. Mus. Zool. Univ. 
Mich. 516:1-40. 
Bohlke, James E., and F. C. Rohde. 1980a. Elassoma evergladei Jordan, 
Everglades pygmy sunfish, p. 584; 1980b. Elassoma okefenokee Bohlke, 
Okefenokee pygmy sunfish, p. 585; 1980c. Elassoma zonatum Jordan, 
banded pygmy sunfish, p. 586. In D. S. Lee, C. R. Gilbert, C. H. Hocutt, 
R. E. Jenkins, D. E. McAllister and J. R. Stauffer, Jr., editors. Atlas of 
North American Freshwater Fishes. N. C. State Mus. Nat. Hist., Raleigh. 
Burgess, George H. 1980a. Poecilia latipinna (Lesueur), sailfin molly, p. 549; 
1980b. Percina nigrofasciata (Agassiz), blackbanded darter, p. 730; 1980c. 
Centropomus parallelus Poey, fat snook, p. 570; 1980d. Centropomus pec- 
tinatus Poey, tarpon snook, p. 571; 1980e. Centropomus undecimalis 
(Bloch), snook, p. 572. In D. S. Lee et al., editors. Atlas of North American 
Freshwater Fishes. 
