Color Changes, Unusual Melanosomes, and a New Pigment from Leaf Frogs

  title={Color Changes, Unusual Melanosomes, and a New Pigment from Leaf Frogs},
  author={Joseph T. Bagnara and J. David Taylor and Giuseppe Prota},
  pages={1034 - 1035}
Melanosomes of phyllomedusid frogs are unusually large and are composed of an amorphous matrix of thick fibers. Their hitherto undescribed dark red pigment is neither phaeomelanin nor eumelanin, but seems to be related to melanins. Melanophores of at least one of these species, Agalychnis dacnicolor, exhibit color change in direct response to illumination, and it is suggested that these chromatophores are innervated. 

Localization of rhodomelanochrome in melanosomes of leaf frogs.

The appearance of the electron-dense core of the melanosomes of untreated skin is unchanged and it is suggested that the leaf frog melanosome is composed of an inner kernel of eumelanin and an outer fibrous component of rhodomelanochrome.

Common origin of pigment cells.

It is proposed that the various pigment cells are derived from a stem cell that contains a primordial organelle of endoplasmic reticular origin that can differentiate into any of the known pigmentary organelles.

Enigmas of pterorhodin, a red melanosomal pigment of tree frogs.

A variety of tree frog species from Australia and Papua New Guinea also possess pterorhodin and the large melanosome suggesting that tree frogs from the New World and those from Australia are closely related and may have been separated during continental drift.

An analysis of color change phenomena in the leaf frog, Agalychnis dacnicolor

Experiments involving denervation and electrical stimulation both in vivo and in vitro fail to implicate a chromatophore control by innervation, and a color index is established for the assessment of color change in the absence of melanophore visibility.

Genetic control of melanophore ultrastructure in Poecilia reticulata

A melanic mutant form, Nigrocaudatus II, of the guppyfish Poecilia reticulata has been found to have a melanophore distribution different from, and a melanosome size significantly larger than, the

The morphology of dermal chromatophores in the infrared‐reflecting glass‐frog Centrolenella fleischmanni

It is suggested that the unusual new pigment cell contributes significantly to the overall green color of C. fleischmanni.

Visual pigment in fish iridocytes

Using an immunofluorescence technique, the identification of an opsin-based visual pigment within the neon tetra iridophore is described, located within the cell itself, or very close to it.



Melanosomes of the Mexican tree frog Agalychnis dachnicolor.

Animal Colour Changes and their Neurohumours

THIS is a very valuable compilation of literature A on chromatic function which, together with previous reviews by Fuchs (1910) and Hogben (1924), makes readily accessible all references on the


Pale coloration ranging from tan to green is provided by the overlying xanthophores and iridophores, and the nature of the intimate contact between the chromatophore types is discussed.

Nishioka for providing A. moreleti and A. callidryas preparations. This work was made possible by grants GB-27639 and GB-16329 from the National Science Foundation

    Its Genesis and Control, V

    • Riley, Ed. (Appleton-Century-Crofts, New York, 1972), pp. 171-180; J. D. Taylor and J. T. Bagnara, Am. Zool. 12, 43 (1972); J. T. Bagnara and M. E. Hadley, Chromatophores and Color Change
    • 1973

    callidryas preparations. This work was made possible by grants GB-27639 and GB-16329

    • National Science Foundation
    • 1973