Morphological variations of Gnathonemus petersii (Günther, 1862) (Pisces, Mormyridae) based on museum preserved adult specimens
2
조회
0
다운로드
0
인용
0
참고문헌
키워드
초록
Examination of the morphometric (measurable) and meristic (countable) characteristics in fish is important for the differentiation of taxonomic units to spot differences in fishes. The taxonomical study of African freshwater mormyrids is of great interest because of their morphological diversification. Therefore, the study of variations in morphological traits among fish species has been conventionally based on comparisons of adults. In this study, morphological variations were studied for Gnathonemus petersii based on museum deposited adult specimens collected from African rivers. Specimens were previously (2015) collected, identified, tagged, and deposited in the Royal Museum for Central Africa. The study was based on 29 measurable and eight countable traits along with character definitions to compare morphological variations in G. petersii. Accordingly, the 29 measurable traits were measured using a caliper, and meristic enumerations were supported by dissecting microscope. Overall, a total of 119 individuals of G. petersi were measured and enumerated for their morphometrics and meristics, respectively, to interpret intraspecific variations. Counts of pelvic and pectoral fins for all specimens were the same (6 and 10, respectively) and excluded for the analysis. However, specimens collected from the Wouri and Sanaga Rivers showed some grouping being isolated from Nigerian specimens. Out of the 29 morphometric variables measured, 18 variables showed slight differences. In the present study, the test for clear separation analysis applied for the G. petersi species using morphometric measurements showed slight separations in between specimens collected from Congo and Sanaga. Generally, the morphometric measurements, which represent standard length (%SL) and head length (%HL) were the most discriminate characters used in the present analysis. Although systematic ichthyologists continue to depend heavily on morphological variations for taxonomic characters, the value and availability of genetic, physiological, behavioral, and ecological data need to be used in modern fish nomenclature.
Abstract
Examination of the morphometric (measurable) and meristic (countable) characteristics in fish is important for the differentiation of taxonomic units to spot differences in fishes. The taxonomical study of African freshwater mormyrids is of great interest because of their morphological diversification. Therefore, the study of variations in morphological traits among fish species has been conventionally based on comparisons of adults. In this study, morphological variations were studied for Gnathonemus petersii based on museum deposited adult specimens collected from African rivers. Specimens were previously (2015) collected, identified, tagged, and deposited in the Royal Museum for Central Africa. The study was based on 29 measurable and eight countable traits along with character definitions to compare morphological variations in G. petersii. Accordingly, the 29 measurable traits were measured using a caliper, and meristic enumerations were supported by dissecting microscope. Overall, a total of 119 individuals of G. petersi were measured and enumerated for their morphometrics and meristics, respectively, to interpret intraspecific variations. Counts of pelvic and pectoral fins for all specimens were the same (6 and 10, respectively) and excluded for the analysis. However, specimens collected from the Wouri and Sanaga Rivers showed some grouping being isolated from Nigerian specimens. Out of the 29 morphometric variables measured, 18 variables showed slight differences. In the present study, the test for clear separation analysis applied for the G. petersi species using morphometric measurements showed slight separations in between specimens collected from Congo and Sanaga. Generally, the morphometric measurements, which represent standard length (%SL) and head length (%HL) were the most discriminate characters used in the present analysis. Although systematic ichthyologists continue to depend heavily on morphological variations for taxonomic characters, the value and availability of genetic, physiological, behavioral, and ecological data need to be used in modern fish nomenclature.