Scientists from India, Belgium and the USA found that the Bombay night frog, also known as Nyctibatrachus humayuni, is used to fertilize a previously unknown position. Until now it was thought that frogs are practicing six different variants of fertilization, however, the new data show that they, at least, seven.
In order to leave offspring, tailless amphibians, including frogs, use amplexus. The essence of this variant of pseudocopulation is that the female lays eggs and the male (usually at this time one way or another in contact with a female) almost immediately impregnates this game.
As the researchers report, 6650 species of frogs, so far examined, have resorted to one of six different options of amplexus: inguinal, axillary, head-covering and adhesive varieties, as well as independent situation in which individuals are placed back-to-back to each other and not directly touching. The seventh approach, discovered by scientists recently, is that the male climbs on the female and leaves his sperm on her back after which the female lays eggs which is fertilized with sperm that her back flows. The uniqueness of this approach is, first, that the male at the moment of fertilization “scene” is not already present.
Most of the previously known species of amplexus implies that the male holds the female throughout pseudocopulation. Thus, the new position requires significantly more “responsible” behavior of females. However, the researchers found some evidence that females Nyctibatrachus humayuni play a more active role in reproduction than many other types of frogs: in particular, they, like the males emit mating calls.
Since the Bombay night frog spawn exclusively in the rainy season and at night, to observe this process very difficult. In this case, helped scientists first used with this purpose, an infrared camera.
Experts also the first time watched as the eggs Nyctibatrachus humayuni eats snake.