Walking Catfish

Walking catfish are very cool. However, isn't the current hypothesis that legs, etc, developed in shallow-water bottom dwellers before they decided on froggy goes awalking? If that was the case, I like the Ambystomatidae family of salamanders as a better modern example, especially this little guy (Ambystoma mexicanum): Innit cute? Note the fully developed limbs and hands, coupled with the feather gills of an obligate water dweller. This species (and a few others of the family) remains neotenic, although the majority of the 30-odd species in the family metamorphose into land dwelling amphibians. Here's a pic of one of the metamorphosed A. mexicanum - very rare, and indistinguishable from A. tigrinum: fixed pic width, hhmm doesn't seem to do anything to page width tho - The Queen[This message has been edited by AdminAsgara, 12-05-2003][This message has been edited by AdminAsgara, 12-05-2003]{Bumped the width of 2nd photo from 60% to 80%, page width was fine at 60%, and (in preview anyhow) also at 80% - AM}[This message has been edited by Adminnemooseus, 12-05-2003]

There are, actually, quite a few of the salamanders which are fully aquatic in both larval and adult forms. I like the hellbenders (ex, Cryptobranchus alleganiensis) of the Cryptobranchidae subfamily (Urodela): Although you can't really see it in this adult pic, the little guy has fully functioning gills. Does this work?PS: Notice the resemblance to your avatar?[This message has been edited by Quetzal, 12-04-2003]

You have a good point. Salamanders are probably not "transitional" in the sense of demonstrating the sequence from water to land. They're pretty derived, and separated out from the Anurans sometime during the Mesozoic (IIRC). I'll see if I can remember any other extant critters that are closer to the mark, but anything around today would be pretty much at a long-evolved (i.e., derived) state. IOW, your objection concerning the terrestrial/aquatic line - at least in amphibians - would probably still apply.OTOH, I think that fishies coming up on land like lp's catfish or Chiroptera's mudskippers blur the terrestrial/aquatic distinction more than a bit. There's also some of the Blenniidae that can live out of water for awhile and even one that lives in intertidal pools and deliberately jumps out of the water to escape predators - and can sit around for up to ten minutes (I can't remember which species). IMO, while they may not represent transitionals in the sense your avatar does, the DO show that things are still coming ashore...

Erm, I thought you wanted a fully aquatic tetrapod? The hellbender sure seems to be in the running. Maybe you could define a little more clearly what you're asking?