TY - JOUR
T1 - Morphometric variation of Middle-American cichlids
T2 - Theraps–Paraneetroplus clade (Actinopterygii: Cichliformes: Cichlidae)
AU - Aguilar-Contreras, Yanet Elizabeth
AU - González-Díaz, Alfonso A.
AU - Mejía, Omar
AU - Rodiles-Hernández, Rocío
N1 - Publisher Copyright:
© Aguilar-Contreras et al.
PY - 2021
Y1 - 2021
N2 - This study assesses the patterns of variation in body shape, and relations of morphological similarity among species of the Theraps– Paraneetroplus clade in order to determine whether body shape may be a trait in phylogenetic relations. A total of 208 specimens belonging to 10 species of the Theraps–Paraneetroplus clade were examined. The left side of each specimen was photographed; in each photograph, 27 fixed landmarks were placed to identify patterns in body shape variation. Images were processed by using geometric morphometrics, followed by a phylogenetic principal component analysis. The phylogenetic signal for body shape was then calculated. To determine the relations in morphological similarity, a dendrogram was created using the unweighted pair group method and arithmetic mean values, while a Procrustes ANOVA and post-hoc test were used to evaluate significant differences between species and habitats. We found three morphological groups that differed in body length and depth, head size, and the position of the mouth and eyes. The body shape analysis recovered the morphotypes of seven species, and statistical differences were demon-strated in eight species. Based on traits associated with cranial morphology, Wajpamheros nourissati (Allgayer, 1989) differed the most among the species examined. No phylogenetic signal was found for body shape; this trait shows independence from ancestral relatedness, indicating that there is little congruence between morphological and genetic interspecific patterns. As evidenced by the consistently convergent morphology of the species in the Theraps–Paraneetroplus clade, the diversification of the group is related to an ecological opportunity for habitat use and the exploitation of food resources. Although no phylogenetic signal was detected for body shape, there appears to be an order associated with cranial morphology-based phylogeny. However, it is important to evaluate the intraspecific morphologic plasticity produced by ecological segregation or partitioning of resources. Therefore, future morphological evolutionary studies should consider cranial structures related to the capture and processing of food.
AB - This study assesses the patterns of variation in body shape, and relations of morphological similarity among species of the Theraps– Paraneetroplus clade in order to determine whether body shape may be a trait in phylogenetic relations. A total of 208 specimens belonging to 10 species of the Theraps–Paraneetroplus clade were examined. The left side of each specimen was photographed; in each photograph, 27 fixed landmarks were placed to identify patterns in body shape variation. Images were processed by using geometric morphometrics, followed by a phylogenetic principal component analysis. The phylogenetic signal for body shape was then calculated. To determine the relations in morphological similarity, a dendrogram was created using the unweighted pair group method and arithmetic mean values, while a Procrustes ANOVA and post-hoc test were used to evaluate significant differences between species and habitats. We found three morphological groups that differed in body length and depth, head size, and the position of the mouth and eyes. The body shape analysis recovered the morphotypes of seven species, and statistical differences were demon-strated in eight species. Based on traits associated with cranial morphology, Wajpamheros nourissati (Allgayer, 1989) differed the most among the species examined. No phylogenetic signal was found for body shape; this trait shows independence from ancestral relatedness, indicating that there is little congruence between morphological and genetic interspecific patterns. As evidenced by the consistently convergent morphology of the species in the Theraps–Paraneetroplus clade, the diversification of the group is related to an ecological opportunity for habitat use and the exploitation of food resources. Although no phylogenetic signal was detected for body shape, there appears to be an order associated with cranial morphology-based phylogeny. However, it is important to evaluate the intraspecific morphologic plasticity produced by ecological segregation or partitioning of resources. Therefore, future morphological evolutionary studies should consider cranial structures related to the capture and processing of food.
KW - Diversification
KW - Geometric morphometrics
KW - Morphological convergence
KW - Phylogenetic signal
KW - Usumacinta province
UR - http://www.scopus.com/inward/record.url?scp=85123102749&partnerID=8YFLogxK
U2 - 10.3897/aiep.51.69363
DO - 10.3897/aiep.51.69363
M3 - Artículo
AN - SCOPUS:85123102749
SN - 0137-1592
VL - 51
SP - 403
EP - 412
JO - Acta Ichthyologica et Piscatoria
JF - Acta Ichthyologica et Piscatoria
IS - 4
ER -