Acestrorhynchus heterolepis

Toledo-Piza, Mônica, 2007, Phylogenetic relationships among Acestrorhynchus species (Ostariophysi: Characiformes: Acestrorhynchidae), Zoological Journal of the Linnean Society 151 (4), pp. 691-757 : 747

AUTAPOMORPHIES OF A. HETEROLEPIS

102. Sphenotic spine extending anteriorly to transverse plane through joint between pterosphenoid and orbitosphenoid (character 20, 0> 1).

103. Posteriorly discontinuous margins of infraorbitals 3 and 4, in which dorsal margin of third infraorbital does not extend along entire ventral margin of fourth infraorbital (character 35, 0> 1).

104. Endopterygoid arranged in a single row on posteroventral portion of endopterygoid (character 50, 0> 4 under hypothesis 1; 2> 4 – interpretation of character state transformation ambiguous under hypothesis 2).

105. Lack of any characteristic pattern of pigmentation laterally on body (character 103, interpretation of character state transformation ambiguous). Independently acquired in A. minimus .

106. Hypothesis 1: further development of ventral diverging lamella of mesethmoid (character 1, 1> 2). Independently acquired in clade formed by A. isalineae and A. nasutus .

107. Hypothesis 1: presence of an enlarged foramen on posteroventral portion of lateral wing of mesethmoid (character 2, 0> 1). Independently acquired in clade formed by A. isalineae and A. nasutus .

108. Hypothesis 1: interdigitating shape of anterior projection of vomer that overlaps posteroventral portion of mesethmoid (character 6, 1> 0). Independently acquired in A. falcirostris .

109. Hypothesis 1: presence of premaxillary foramen that receives anteriormost dentary conical tooth similar in size to foramen that receives dentary canine (character 42, 1> 2). Independently acquired in the clade formed by A. isalineae and A. nasutus .

The presence of the laterosensonsory canal with an upper and a lower small branch on each scale of the lateral line distinguishes A. heterolepis from the remaining species of Acestrorhynchus ( Menezes, 1969) . A detailed comparison of branching patterns of the laterosensory canal in the lateral line among outgroup taxa was not performed in the present study, but within Acestrorhynchus this feature is restricted to A. heterolepis . On the basis of the most parsimonious hypotheses derived from the present analysis it is proposed as autapomorphic for that species. The presence of a small round dark blotch on the dorsal portion of the opercle (character 104, 0> 1) is also proposed as autapomorphic for that species.