As Amplexus (Latin, Embrace ) the condition of the clutches of females of anurans ( and a few newts ) is designated by the males during the mating season. It is a staple reflex. This behavior serves to synchronize the process of spawning and sperm release into the water ( external fertilization ).
In the phylogenetically primitive species of the suborders Archaeobatrachia and Mesobatrachia the male bracketed with his arms in the hip or lumbar region of the female, that is, before its hind legs firmly - the so-called amplexus lumbar or inguinal amplexus. Only throat and chest of the male have this contact with the back of the female (compare, for example, toads, Disc-, shovel toads, African clawed frog ).
In the "modern" anurans ( Neobatrachia; see for example toads, tree frogs, True Frogs ) observed the axillary amplexus: The male rises so on the back of the female, that it clasping this behind the front legs. In order to have better grip, develop many types Bruns sealed Wielen. Often the amplexus takes place already during the Laichplatzanwanderung; The males can then piggybacking overland to the propagation waters. This has less by often to do with convenience but with the avoidance of competition in existing outnumbered males.
Mismatches and tangle
During the mating season the hormone- controlled clamp reflex of the male is very pronounced, so they try often impetuous and unselective to encompass any reasonably fit appearing in the form and size of the subject. It is not uncommon to mismatches between different species or even with objects such as driftwood or dead fish ( also see: Common Moorhen ). Also, human fingers are taken, and with amazing clamping force " hugs " when she pushes the male. The males can then easily lift out of the water and removes even then his tight grip often not.
In addition, in the water sometimes results in large " ball " of several mutually clasping copies - especially when spawning in large companies toad, this phenomenon is often observed. It may well come to drowning or suffocation of animals. In particular, the female, the most helpless is somewhere in the middle of the " node " is affected. To keep importunate fellow males in the spawning Society of the body, males have a " Befreiungsruf ", which is to the opposite signal his mistake. This only works within the same species - and even then not always.