Abstrak
this study aimed to find out morphology and abundance of mudskipper on Sebatik Island and the potential for its implementation as learning materials in biology learning. Bsed on the morphology, mudskipper had 5 differentiating characters from 23 morphometric characters. For the relative abudance, the species that was classified as high was the Periophthalmus chrysospilos Bleeker (80,64%), the moderate abudance was found in the species of Boleophthalmus boddarti Pallas (16,12%), and the lowest abundance was found in the species of Periphthalmodon schlosseri Pallas (3,22%). These was a link between research in biology learning, namely vertebrate material for class X SMA and basic competence 3.8, applying the classification principle to classify animals into phyla based on life. The results of this identification were poured into teaching materials in the form of lesson plans, practical, guides, student worksheets and handouts.