This species is distinguished from its congeners by the following characters: with a wide brown stripe in the dorsal and caudal fins in specimens larger than 2.5 cm SL (inconspicuous or absent in small specimens) and by the presence of neuromasts surrounded by melanophores forming small black dots aligned in four rows on head, one on nape, one posterior to nape, and three horizontal on trunk; differs further by the presence or absence of a light band on nape (some paratypes have a small and irregular pale brown blotch on the region nuchal), supraoccipital process not contacting the anterior nuchal plate, width of mouth 34-47% HL (vs. 47-63 in M. carlae, M. cibelae, M. cottoides, M. iheringi, M. malabarbai, M. minutus, M. reikoae, M. nigripinnis, M. oliveirai, M. parahybae, M. pataxo, M. pleriqueater, M. sparsus, M. variegatus), and greater caudal peduncle length 15.9-17.9% SL (vs. 10.0-15.9 in M. carlae, M. cibelae, M. cottoides, M. eurystoma, M. iheringi, M. maculatus, M. malabarbai, M. nigripinnis, M. parahybae, M. pataxo, M. pellopterygius, M. poecilus, M. secundus, M. variegatus) (Ref. 130492).