Acestrorhynchus

Toledo-Piza, Mônica, 2007, Phylogenetic relationships among Acestrorhynchus species (Ostariophysi: Characiformes: Acestrorhynchidae), Zoological Journal of the Linnean Society 151 (4), pp. 691-757: 743-744

publication ID

http://doi.org/ 10.1111/j.1096-3642.2007.00355.x

persistent identifier

http://treatment.plazi.org/id/5C71FF4E-3269-3D25-46AB-FA08E1DAF96F

treatment provided by

Felipe

scientific name

Acestrorhynchus
status

 

MONOPHYLY OF ACESTRORHYNCHUS  

1. Anterior projection of vomer overlapping posteroventral portion of mesethmoid (character 5, 0> 1).

2. Dorsolateral expansion of vomer (character 7, 0> 1).

3. Form of contact between vomer and palatine through modified anterior portion of palatine that abuts matching articular facet of processes located on anteroventral surface of vomer (character 8, 0> 1).

4. Relatively long snout (equal or larger than orbital diameter) (character 12, 0> 1). Snout further elongated in A. heterolepis   , A. isalineae   , and A. nasutus   .

5. Contact between rhinosphenoid and parasphenoid through well-developed bony expansion on ventral margin of rhinosphenoid (character 14, 0> 1).

6. Sphenotic spine curved anteriorly, with anterior portion more horizontally aligned and posterior portion more vertically aligned (character 19, 0> 2).

7. Lateral process of frontal contacting anterolateral margin of sphenotic spine (character 21, 0> 1). Reversed in clade formed by A. grandoculis   and A. minimus   , and in A. nasutus   .

8. Dilatator groove with large anterior opening for passage of dilatator operculi muscle entirely bordered by frontal (character 22, 0> 1). Reversed in clades formed by A. grandoculis   and A. minimus   , and A. isalineae   and A. nasutus   .

9. Lack of prominent sharp-edged ridge on lateral comissure of prootic (character 23, 0> 1).

10. First infraorbital extending along entire ventral margin of second infraorbital, and completely overlying maxilla (character 30, 0> 2).

11. First infraorbital flap-like process originating on middle portion of dorsal border of that ossification, and extending medially, overlying maxilla dorsally (character 31, 0> 1).

12. Thin and elongate process on ventral surface of supraorbital (character 38, 0> 1). Further modified in A. falcirostris   and in the clade formed by A. altus   , A. abbreviatus   , A. falcatus   , A. lacustris   , and A. pantaneiro   .

13. Premaxillary foramen that receives first dentary canine (character 41, 0> 1).

14. A second premaxillary foramen that receives anteriormost dentary conical tooth smaller than foramen that receives dentary canine (character 42, 0> 1). Foramen further enlarged in A. heterolepis   , A. isalineae   , and A. nasutus   .

15. Pattern of maxillary teeth consisting of two canines anteriorly, either two or three conical teeth in between, followed by one large conical tooth and a series of small conical teeth along entire ventral margin of maxilla (character 44, 0> 1).

16. Presence of projection on dorsal margin of maxilla (character 45, 0> 1).

17. Presence of depression on lateral portion of dentary, which lodges posterior premaxillary canine when mouth is closed (character 47, 0> 1).

18. Internally displaced dentary teeth (character 48, 0> 1).

19. Presence of anterior process of hyomandibula extending along dorsolateral margin of metapterygoid (character 54, 0> 1).

20. Presence of flange on dorsoposterior portion of opercle (character 56, 0> 1).

21. Lack of ventrolateral lamella on each side of urohyal (character 59, 0> 1).

22. Lack of gill rakers on trailing edge of fourth ceratobranchial (character 64, 0> 1). Reversed in A. minimus   .

23. Anterior portion of basibranchial 3 with laminar projection contacting corresponding laminar projection on posterior portion of basibranchial 2 by means of variously developed interdigitations (character 66, 0> 1). Modified in A. abbreviatus   .

24. Ossified fourth basibranchial (character 67, 0> 1). Reversed in A. falcirostris   .

25. Transverse process of third neural arch projecting laterally (character 71, 0> 1).

26. Laterosensory canal of sixth infraorbital unbranched (character 93, 0> 1).

27. Laterosensory canal completely surrounded by bone entering premaxilla (character 98, 0> 1).

28. Presence of branch on laterosensory canal of posttemporal (character 100, 0> 1).

Ambiguous characters

29. Segment of supraorbital laterosensory canal of frontal between pterotic and point where parietal branch exits supraorbital canal, greatly reduced, and pterotic canal extending anteriorly onto position primitively occupied by supraorbital laterosensory canal (character 94, 0> 1). Reversed in A. falcirostris   and clade formed by A. altus   , A. abbreviatus   , A. falcatus   , A. lacustris   , and A. pantaneiro   .

30. Communication between laterosensory canal of sixth infraorbital and cephalic canals through independent opening in supraorbital canal in frontal, with no participation of pterotic canal (character 95, 0> 1). 31. Hypothesis 1: presence of posteriorly directed process on each side of distal portion of proximal radial of seventh anal-fin pterygiophore (character 88, 0> 1). Reversed in clade that includes A. heterolepis   ; A. altus   , A. abbreviatus   , A. falcatus   , A. lacustris   , and A. pantaneiro   .

32. Hypotheses 2: reduced and ventrally shifted posterior margin of lateral wing of mesethmoid (character 3, 0> 1). Reversed in clade that includes A. heterolepis   , A. isalineae   , A. falcirostris   , and A. nasutus   ; shelf absent in clade formed by A. britskii   , A. grandoculis   , A. microlepis   , and A. minimus   .

33. Hypothesis 2: well-developed lateral branch of laterosensory canal of fourth infraorbital (character 92, 0> 1). Reversed in clade formed by A. heterolepis   , A. isalineae   , A. falcirostris   , and A. nasutus   .