Corresponding author: Marcelo C. Andrade (
Academic editor: C. Baldwin
Andrade MC, Jégu M, Giarrizzo T (2016) A new large species of
Three species are recognized within the genus
From the material collected in the Rio Madeira Basin, Brazil, a previously undescribed species was identified by
Counts and measurements were performed as described by standard length head length
The institutional abbreviations follow
Paratypes. All from Brazil. INPA 50868 (3 specimens 183.8–339.5 mm
Prepelvic area of abdomen in ventral view of
Ventral view of skeletonized premaxilla.
Morphometric data is presented in Table
Morphometric data of = standard deviation
Holotype | Range | Mean |
|
|
---|---|---|---|---|
Standard length (mm) | 326.2 | 183.8–351.1 | 282.9 | * |
Percentages of standard length | ||||
Body depth | 59.3 | 59.1–62.5 | 60.4 | 1.3 |
Head length | 24.3 | 21.8–24.6 | 23.4 | 0.9 |
Supraoccipital process | 26.0 | 25.9–29.6 | 27.8 | 1.3 |
Predorsal length | 53.7 | 51.9–55.8 | 54.1 | 1.3 |
Dorsal-fin base length | 29.2 | 27.6–30.1 | 29.0 | 0.7 |
Interdorsal length | 12.1 | 11.4–12.7 | 12.1 | 0.5 |
Adipose-fin base length | 6.7 | 5.6–6.7 | 6.1 | 0.4 |
Caudal peduncle depth | 10.8 | 10.1–11.1 | 10.6 | 0.3 |
Anal-fin base length | 33.6 | 32.3–35.3 | 33.7 | 1.0 |
Preanal length | 77.6 | 72.5–79.1 | 76.9 | 1.9 |
Prepelvic length | 58.7 | 54.7–59.0 | 57.5 | 1.4 |
Prepectoral length | 24.6 | 23.5–25.3 | 24.5 | 0.6 |
Anal-pelvic distance | 21.5 | 21.2–24.0 | 22.6 | 1.0 |
Pelvic-pectoral distance | 36.1 | 32.3–36.1 | 34.1 | 1.4 |
Width of peduncle | 5.1 | 3.7–5.3 | 4.4 | 0.7 |
Pectoral-fin length | 20.4 | 19.1–20.9 | 20.2 | 0.6 |
Pelvic-fin length | 15.5 | 13.9–16.1 | 15.0 | 0.7 |
First anal-fin lobe length | 30.7 | 24.0–32.4 | 29.4 | 3.5 |
Second anal-fin lobe length | * | 13.9–18.2 | 15.4 | 2.4 |
Dorsal-fin length | 27.9 | 25.2–31.1 | 28.2 | 1.6 |
Distance dorsal-fin origin to anal-fin origin | 64.9 | 62.0–65.9 | 64.6 | 1.1 |
Distance dorsal-fin end to anal-fin origin | 49.0 | 46.9–49.6 | 48.5 | 0.9 |
Distance dorsal-fin end to anal-fin end | 26.0 | 24.1–26.7 | 25.3 | 0.8 |
Percentages of head length | ||||
Snout length | 31.2 | 29.3–33.7 | 31.4 | 1.4 |
Interorbital width | 53.8 | 49.2–56.5 | 53.0 | 2.7 |
Head width | 66.8 | 64.9–71.1 | 68.4 | 2.3 |
Postorbital distance | 34.2 | 32.8–36.6 | 34.0 | 1.2 |
Fourth infraorbital width | 16.2 | 14.6–19.6 | 16.9 | 1.4 |
Eye vertical diameter | 27.4 | 27.3–35.4 | 30.9 | 2.9 |
Mouth length | 17.6 | 14.4–18.2 | 16.9 | 1.4 |
Third infraorbital width | 11.8 | 11.8–14.1 | 12.9 | 0.8 |
Cheek gap width | 9.9 | 9.2–12.6 | 11.1 | 1.1 |
Mouth width | 36.1 | 31.7–38.5 | 35.9 | 2.0 |
Snout gently rounded, mouth terminal, slightly oriented dorsally; jaws equal in size. Labial row of premaxillary teeth separated from lingual row by a gap; five teeth in labial row and two teeth in lingual row (Fig.
Scales cycloid, lateral line with 80 (1), 81 (3), 82 (2), or 83* (2) perforated imbricate scales from supracleithrum to hypural joint; total perforated scales 85 (1), 86 (2), 87 (1), 88* (2), or 89 (2). Scale rows between dorsal-fin origin and lateral line 39 (1), 40* (3), 41 (2), or 42 (2). Scale rows between lateral line and pelvic-fin insertion 36 (2), 38* (2), 39 (2), 40 (1), or 42 (1). Circumpeduncular scales 34 (1), 35* (3), or 36 (4). Prepelvic serrae with 13 (1), 17 (2), 18 (2), or 19* (3) very reduced spines (Fig.
Pectoral-fin rays i, 16 (2), i, 17 (5), or i, 18* (1). Pelvic-fin rays i, 7* (7), or i, 8 (1). Dorsal-fin origin at midbody preceded by strong forward-directed spine. Dorsal-fin rays ii* (4), or iii (4), and 20 (3), 21* (4), or 22 (1); anteriormost rays longest. Anal-fin rays iii (7), or iv* (1), and 32 (3), 33* (2), or 34 (3). Adipose fin with sub-rectangular distal margin. Caudal fin forked into lobes of similar size.
Total vertebrae 40 (1), or 41 (2). Predorsal vertebrae 10 (3). Postdorsal vertebrae 15 (2), or 16 (1). Vertebrae through last dorsal-fin pterygiophore and first anal-fin pterygiophore 2 (1), or 3 (2). Supraneurals 6 (3). Neurocranium in lateral view high, short, triangular, with concavity at epiphyseal bar level. Ascending process of premaxilla broader from its base to tip, with slightly rounded edge (Fig.
Collecting localities of
The type locality of
Corredeira dos Periquitos, Rio Aripuanã, type locality of
The specific name ‘
Several classifications of
The authors would like to thank Lúcia Rapp Py-Daniel, Renildo Oliveira, and Douglas Bastos (INPA), Valéria Machado (UFAM), Wolmar Wosiacki and Izaura Magalhães (MPEG), Cecile Gama (