Left-facing Fish

Well, the gang’s (almost) all here!

These fish are on their way to a taxonomic key to the freshwater fishes of the Talamanca region, Costa Rica.  It’s a project that I’ve been chipping away at from time to time for the last few months.  It led me from icy Pennsylvania to beautiful Costa Rica to a lockdown at the Smithsonian Museum Support Center… but that’s a story for another day.  Enjoy!

Superior mouth (Alfaro)

Inferior mouth (Sicydium)

Subterminal mouth (Brycon)

Terminal mouth (Astyanax)

Protractile mouth (Eucinostomus)

Eyes on left side of body (Citharichthyes)

Eyes on right side of body (Trinectes)

Rounded sucker (Sicydium)

Elongated sucker (Awaous)

Rounded caudal fin

Truncate caudal fin

Emarginate caudal fin

Forked caudal fin

Triangular humeral spot (A. aeneus)

Rounded humeral spot (A. orthodus)

Spine serrated on one side (R. rogersi)

Spine serrated on both sides (R. guatemalensis)

Branchial opening aligned with eye (Gobiomorus)

Branchial opening aligned with preoperculum (Eleotris)

Short snout (Pseudophallus)

Long snout (Microphis)

Body covered in bony plates

Uninterrupted lateral line

Broken lateral line (Astatheros)

Anal fin modified into long gonopodium (phallichthys)

Preopercular lobe (P. managuensis)

No preopercular lobe (P. loiselli)

Straight snout (C. unidecimalis)

Convex head (Agonostomus)

Concave snout (C. pectinatus)

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