Figure 1.
Map of South America showing the northern hydrology and the localities where the specimens were collected (grey and green marks).
Table 1.
Taxonomic sampling and accession numbers.
Figure 2.
Neighbor-Joining tree based on the barcode region of the COI.
The numbers near the branches represent bootstrap probabilities higher than 50%.
Figure 3.
Maximum-likelihood phylogeny based on the barcode region of the COI marker.
The numbers near the branches represent the bootstrap probabilities.
Figure 4.
Distribution of K2P distances (%) for COI: A) within species; B) within genera; C, normalized distribution of K2P distance (%) within species.
The analyses included the following taxa: Tetraodon nigroviridis, Tetraodon biocellatus, Sphoeroides testudineus, Lagocephalus laevigatus, Colomesus asellus, Colomesus psittacus, and the freshwater Colomesus from the Tocantins drainage.
Figure 5.
Neighbor-Joining phylogeny of the freshwater Colomesus and haplotype determination.
Figure 6.
External morphology of the genus Colomesus.
A) Colomesus tocantinensis nov. sp. – Tocantins (holotype PNT.UERJ.405 highlighted in white); B) Colomesus asellus – Iquitos; C) Colomesus asellus – Belém.
Table 2.
Morphometric and meristic data of the type series of Colomesus tocantinensis nov. sp.
Figure 7.
Colomesus tocantinensis nov. sp. (PNT.UERJ.398).
A) left photograph of the head; B) anatomical interpretations. Abbreviations: Ang, angular; Art, articular; Boc, basioccipital; Brstgs, branchiostegals; Cl, cleithrum; Den, dentary; Epi, epiotic; Ethm, ethmoid; Exo, exoccipital; Fr, frontal; Hyo, hyomandibula; Ecptg, ectopterygoid; Mept, mesopterygoid; Mtptg, metapterygoid; Mx, Maxilla; Op, opercle; Pal, palatine; PCl.l/r, ventral post-cleithrum left and right; Pfr, prefrontal; PMx, premaxilla; Pop, preopercle; Pro, prootic; Psph, parasphenoid; Pto, pterotic; Qua, quadrate; R, radials; Scl, supracleithrum; Soc, supraocciptal; Sop, subopercle; Sphe, sphenotic; Sym, sympletic; Vo, vomer. Scale bar equals 5 mm.
Figure 8.
Colomesus tocantinensis nov. sp. (PNT.UERJ.398).
A) top photograph of the head; B) anatomical interpretations. Abbreviations: Epi, epiotic; Ethm, ethmoid; Exo, exoccipital; Fr, frontal; Pal, palatine; Pfr, prefrontal; PMx, premaxilla; Pto, pterotic; Scl, supracleithrum; Soc, supraocciptal; Sphe, sphenotic. Scale bar equals 5 mm.
Figure 9.
Right and top photographs from cleared-and-stained specimens of: A–B) Colomesus tocantinensis nov. sp. – Tocantins (PNT.UERJ.398); C–D) Colomesus asellus – Iquitos (PNT.UERJ.470); E–F) Colomesus asellus – Belém (PNT.UERJ.386).
Figure 10.
Isolated opercles from: A) Colomesus tocantinensis nov. sp. – Tocantins (PNT.UERJ.398); B) Colomesus asellus – Iquitos (PNT.UERJ.470); C) Colomesus asellus – Belém (PNT.UERJ.386); D) Colomesus psittacus – Belém (PNT.UERJ.387).
Scale bar equals 1
Figure 11.
Isolated branchial apparatus from: A) Colomesus tocantinensis nov. sp. – Tocantins (PNT.UERJ.404); B) Colomesus asellus – Iquitos (PNT.UERJ.470); C) Colomesus asellus – Belém (PNT.UERJ.386).
Scale bar equals 2.5
Figure 12.
Colomesus tocantinensis nov. sp. (PNT.UERJ.403).
A) left photograph of the unpaired fins and caudal endoskeleton; B) anatomical interpretations. Abbreviations: E, epural; H, dorsal hypural plate; H-H, ventral hypural plate fused with the ural centrum; Phy, parhypural; PU, pre-ural vertebrae; PbD, dorsal-fin basal pterigiophores; PbA, anal-fin basal pterigiophores. Scale bar equals 5 mm.
Figure 13.
Left view photographs from cleared-and-stained specimens of: A) Colomesus tocantinensis nov. sp. (PNT.UERJ.403); B) Colomesus asellus – Iquitos (PNT.UERJ.470); C) Colomesus asellus – Belém (PNT.UERJ.386).
Scale bar equals 5
Figure 14.
High-definition x-ray images of: A–D, Colomesus psittacus USNM.393077; E–G, Colomesus asellus USNM.191569.
Scale bar equals 10