Fiddler crab Fiddler crab A fiddler crab, sometimes known as a "calling crab", may be any of approximately 100 species of semi-terrestrial marine crabs which make up the genus Uca. As members of the family Ocypodidae, fiddler crabs are most closely related to the ghost crabs of the genus "Ocypode". This entire group is composed of small crabs – the largest being slightly over two inches across. Fiddler crabs are found along sea beaches and brackish inter-tidal mud flats, lagoons and swamps. Fiddler crabs are most well known for their sexually dimorphic claws; the males’ major claw is much larger than the
Hermit (hummingbird) very decurved bills. Many species, including the rufous-breasted hermit, also use the heliconias for nesting, attaching their conical nest to the underside of one of the plant's broad leaves. The taxonomy of some groups has changed significantly in recent years. Apart from those issues discussed at "Phaethornis", a taxonomic problem occurs with the "Threnetes leucurus"/"T. niger" complex. Schuchmann & Hinkelmann (1999) considered the sooty barbthroat a melanistic variant of the "T. leucurus", but as it was described first, its scientific name was adopted for the entire species; pale-tailed barbthroat ("T. niger"). This, however, has not been accepted by all authorities,