18 января, 2016 
Pokraskin The larvae of cichlid fish can attach themselves at the location of emergence during the course of several days after emergence by using the secretions of an adhesive apparatus, which is very variable among the species and allows the larvae to remain under parental defense for several days. As a rule, this apparatus consists of three pairs of cup-shaped glands which are located on the dorsal surface of the larval head and produce a filamentous secretion. Later, the larvae leave and their attachment organs disappear. The secretion gives a positive histochemical reaction for polysaccharides [108-111].
In larval ascidias, the anterior end of the cephalenteron bears three adhesive papillae which enable the larva to attach to the substrate just prior to metamorphosis. In early studies, these have often been referred to as ‘suckers’, but more recent investigations [112] have provided evidence concerning the adhesive nature of these organs. The papillae bear two types of cell (A and B); the first type is a typical secretory cell, while the second is most likely sensory in nature [113]. The A-cells produce proteins and mucopolysaccharides, which often occur in marine organisms as those providing attachment.
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