Discrimination of species and populations of the genus <i>Cichla</i> (Cichliformes: Cichlidae) in rivers of the Amazon basin using otolithic morphometry

Mereles, Marcos A.; Sousa, Raniere G. C.; Barroco, Lorenzo S. A.; Campos, Caroline P.; Pouilly, Marc; Freitas, Carlos E.C.

doi:10.1590/1982-0224-2020-0149

Acessibilidade / Reportar erro

Brasil

Español English

sumário « anterior atual seguinte »

Sumário

Original article • Neotrop. ichthyol. 19 (4) • 2021 • https://doi.org/10.1590/1982-0224-2020-0149 copy

Discrimination of species and populations of the genus Cichla (Cichliformes: Cichlidae) in rivers of the Amazon basin using otolithic morphometry

Authorship SCIMAGO INSTITUTIONS RANKINGS

ABSTRACT

The genus Cichla is a highly diverse group, with 16 species already described. Externally, some species are very similar and discriminating between them may be very difficult. Nevertheless, discrimination of fish stocks is essential for management purposes. Morphometric analyses of otoliths have been successfully used to distinguish species and fish stocks, especially in marine environments. This study evaluated whether sagittal otolith shape can be used to discriminate among the species Cichla temensis, C. monoculus, and C. orinocensis, as well as within populations of C. temensis in rivers of the Amazon. Shape indices and Fourier coefficients were used to describe the shape of the otoliths. Among the groups of species, the morphology of the sagittal otolith of C. temensis was totally distinct from the species C. monoculus and C. orinocensis. While among populations of C. temensis, individuals from the Negro and Jatapú Rivers were different, regardless of the methods used. These results confirm the ability to differentiate species and populations by using the morphology of otoliths. However, more research is needed to verify the role of genetic versus environmental and biotic effects, and thus be able to explain the discrimination observed in otoliths.

Keywords:
Amazonian rivers; Fourier analysis; Otolith; Peacock bass; Shape indices

Shape indices	Equation
Form factor	$(4 π \times O A / {O P}^{2})$
Roundness	$(4 O A) \times (π \times {O L}^{2})$
Circularity	$({O P}^{2} / O A)$
Rectangularity	$(O A / O L \times O W)$
Ellipticity	$(O L - O W / O L + O W)$

Species	N	Form factor	Roundness	Circularity	Rectangularity	Ellipticity
C. monoculus (Negro River)	50	0.53 ± 0.04	0.61 ± 0.07	23.67 ± 2.01	0.73 ± 0.08	0.21 ± 0.03
C. orinocensis (Negro River)	36	0.53 ± 0.06	0.53 ± 0.03	23.95 ± 3.71	0.70 ± 0.02	0.25 ± 0.02
C. temensis (Negro River)	41	0.38 ± 0.06	0.53 ± 0.03	33.58 ± 5.42	0.69 ± 0.02	0.24 ± 0.02
C. temensis (Uatumã River)	15	0.46 ± 0.07	1.52 ± 0.09	27.98 ± 4.28	1.39 ± 1.75	-0.21 ± 0.52
C. temensis (Jatapú River)	26	0.35 ± 0.06	1.49 ± .010	36.91 ± 6.42	0.34 ± 0.13	-0.56 ± 6.42

Sociedade Brasileira de Ictiologia Neotropical Ichthyology, Núcleo de Pesquisas em Limnologia, Ictiologia e Aquicultura, Universidade Estadual de Maringá., Av. Colombo, 5790, 87020-900, Phone number: +55 44-3011-4632 - Maringá - PR - Brazil
E-mail: neoichth@nupelia.uem.br

Acompanhe os números deste periódico no seu leitor de RSS

[1] Edited by

Matt Kolmann