TRAITS by the adult form of an organism is called Neoteny.It occurs due to the lack of metamorphosis.In neoteny there is a delay in the development of somatic cells, however, the sexual cells develop at a constant rate due to this the larval stage becomes capable of reproduction.It generally occurs in Amphibians (Urodela)Neoteny is exhibited by the AXOLOTL larva of Ambystoma mexicanumDue to neoteny, they retain their fins & gills throughout LIFE even in the adult form otherwise fins & gills are lost in the adult stage of amphibiansAdapted to live their whole lives in water, they also do not develop eyelidsNeoteny occurs due to the lack of the thyroid-stimulating hormone, which leads to the metamorphic failure of the organism AlytesIt is a GENUS of Frog, commonly known as midwife-toad. It is named so because it carries the fertilized eggs on its back. They SHOW parental care SyconSycon belongs to the phylum Porifera. Sycon is a kind of sponge that is calcareous in nature.Sycons are very small and tube-shaped sponges.SacculinaIt belongs to the phylum arthropod, class crustacea & order rhizocephalaIt is commonly called root-headed barnacle.It lives as a parasite on the crabs.