Malacocephalus occidentalis Goode & Bean, 1885

(Macrouridae, Gadiformes)

Ocorre em todo o Oceano Atlântico, tanto Sul quanto Norte. No Atlântico Ocidental é conhecido desde Cape Cod até a Argentina. Atinge 530 mm de comprimento. É uma espécie bentopelágica que se alimenta de crustáceos, teleósteos e cefalópodes (Bernardes et al. 2005, Muto et al. 2005). Vive no talude continental entre 200 e 1950 m de profundidade, geralmente entre 300 e 500 m.

The collection contains otoliths from 1033 individuals of this species, ranging from 157 to 523 mm of total length. Click here to see the map of the sampling area for the individuals of this species. The following summaries contains data from 113 analysed otoliths. See more detailed data here (in portuguese).

Otoliths from Malacocephalus occidentalis, with total length of A. 179mm; B. 410mm; C. 523mm; internal side A1; B1; C1; external side A2; B2; C2; profile of the ventral region A3; B3; C3; click the figures for larger version*

Morphology:
Shape: elliptic (96%), trapezoidal to elliptic (4%). Anterior region: peaked-round (34%), angled-round (30%), oblique to peaked-round (14%), oblique to angled-round (13%). Posterior region: oblique to peaked-round (35%), oblique-round (33%), oblique to blunt-round (18%), oblique to peaked (14%). Dorsal edge: lobed to sinuate (96%), sinuate (4%). Ventral edge: sinuate to entire (50%), entire (26%), lobed to sinuate (18%), sinuate (6%). Profile: biconvex. Rostrum and antirostrum orientation: in agreement (95%), in disagreement (5%). Rostrum: underdeveloped (96%), Developed (4%). Antirostrum: absent (66%), underdeveloped (34%). Pseudorostrum: absent (51%), underdeveloped (45%), Developed (4%). Pseudoantirostrum: absent. Sulcus acusticus: position supramedian (96%), median (4%), orientation slightly descending (48%), horizontal (47%), descending (4%), slightly ascending (1%), opening ostiocaudal (54%), caudal (22%), pseudo-ostiocaudal (12%), para-ostial (8%), morphology homosulcoid, colliculum homomorphic, ostium elliptic (96%), tubular (3%), oval (2%), cauda elliptic.
Description of the terms used

Morphometry:

Shape indices	Mean ± sd	Minimum	Maximum
OL / TL %	3.05 ± 0.37	2.47	4.97
OH / OL %	55.75 ± 4.71	46.59	69.56
OT / OL %	18.95 ± 1.77	13.18	23.04
OT / OH %	34.26 ± 4.44	21.57	44.39
Circularity	18.02 ± 1.58	14.92	23.49
Rectangularity	0.70 ± 0.02	0.62	0.74

Description of the abbreviations used

* Vouchers:
Collection identifier for the individuals shown on photography and drawings:

14.1.MAOC.REV.AF.611.2 (179 mm)
14.1.MAOC.REV.AF.614.2 (410 mm)
14.1.MAOC.REV.AF.615.1 (523 mm)

For more information about this species: