scholarly journals Morphometric variation of Middle-American cichlids: Theraps– Paraneetroplus clade (Actinopterygii: Cichliformes: Cichlidae)

2021 ◽  
Vol 51 (4) ◽  
pp. 403-412
Author(s):  
Yanet Elizabeth Aguilar-Contreras ◽  
Alfonso A. González-Díaz ◽  
Omar Mejía ◽  
Rocío Rodiles-Hernández

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 demonstrated 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.

2013 ◽  
Vol 63 (2) ◽  
pp. 217-232 ◽  
Author(s):  
Rosalía Aguilar-Medrano

Chromis is a circumglobal tropical and temperate genus with over 84 species of damselfishes. Studies based in osteological and molecular data have cited the relationship between Azurina and Chromis in the eastern Pacific. The main objectives of the study are: (1) to characterize size and shape in all Chromis and Azurina species of the eastern Pacific, (2) explore the phylogenetic signal of external morphology, and (3) present a hypothesis of the diversification process of this group. According to the results, there is no significant relationship between size and shape. The variation in body shape among all species is related to the height of the trunk, position of the snout and eye, and length of the caudal peduncle. The main morphologic variation between Azurina and Chromis is the degree of elongation of the body. Both Azurina species are closely related to C. punctipinnis and C. atrilobata. The morphological pattern of Azurina integrated it into Chromis. The phylogenetic pattern found by geometric morphometric analyses presented a high similarity with previous results based on molecular data. Phylogeny recovered two main clades, slender-bodied and deep-bodied species. This pattern of morphometric variation is closely related to exploitation of two different reef environments.


2020 ◽  
Vol 17 ◽  
pp. 47-53
Author(s):  
A.O. Bamidele ◽  
A.I. Akinpelu

This study examined the differences in cranial morphology of tree squirrel species (Heliosciuru srufobranchium) from four different locations in rainforest part of Nigeria. Locally fabricated live traps made of wire-mesh and steel were used to capture the squirrels. Trapped tree squirrels were immediately transferred to the laboratory in cages, where they were euthanized by placement in a bell-jar containing chloroform-soaked cotton wool. Individuals from two locations (33 from Ile Ife and 49 from Emure Ekiti) were then preliminarily identified to the generic level, using an identification key. Eighty-two (82) skulls were prepared from them, using Long Island Natural History Museum Guide. The sexes of the specimens were determined by visual inspection of the external genitalia. Twenty-seven (27) cranial and six (6) external body parameters were measured using digital Vernier caliper. One-way analysis of variance at p<0.05 was used to determine the difference in measured body parameters and Principal Component Analysis was used to differentiate the measured skull parameters. The results showed that the body parameters; head body length, tail length, tail body length, ear length, hind foot length and body weight measured were slightly different from one location to another. Also, the cranial measurements showed some similarities and differences between the two locations (Ile Ife and Emure Ekiti). In conclusion, the cranial measurements of the tree squirrels from the two locations (Ile Ife and Emure Ekiti) showed slight differences despite the fact that the tree squirrels are from the same genus (H. rufobranchium). Keywords: Heliosciurus rufobranchium; rainforest; tree squirrel; cranial; morphometric


2018 ◽  
Vol 22 (02) ◽  
pp. 179-190
Author(s):  
Michelle Tavares Cardoso Andreu ◽  
Carlos Eduardo Arlé ◽  
Eduardo Motta Carelli Minsky ◽  
Lazaro Laut ◽  
Rafael da Rocha Fortes ◽  
...  

2021 ◽  
Vol 22 (11) ◽  
Author(s):  
Fauziyah FAUZIYAH ◽  
APON Z. MUSTOPA ◽  
FATIMAH FATIMAH ◽  
ANNA I. S. PURWIYANTO ◽  
ROZIRWAN ROZIRWAN ◽  
...  

Abstract. Fauziyah, Mustopa AZ, Fatimah, Purwiyanto AIS, Rozirwan, Agustriani F, Putri WAE. 2021. Morphometric variation of the horseshoe crab Tachypleus gigas (Xiphosura: Limulidae) from the Banyuasin estuarine of South Sumatra, Indonesia. Biodiversitas 22: 5061-5070. Morphological studies are essential for fish resource management, ecology, conservation, and stock assessment. This research was conducted to characterize the morphological variation of the coastal horseshoe crab (Tachypleus gigas) from the Banyuasin estuarine, South Sumatra, Indonesia. The body weight (BW), prosoma width (PW), carapace length (CL), telson length (TEL), and total length (TL) were measured for describing the morphometric variability of T. gigas. A total of 70 T. gigas (32 females and 38 males) were found using trammel net fishing and bottom gillnet during the survey. Multivariate and allometric methods analyzed their morphometric characters. Based on Kruskal- Wallis tests, the result showed a significant difference in somebody measurements (TL and CL) between males and females. The principal component analysis (PCA) results showed that all morphometric characters had a strong correlation in both sexes, so the first principal component (PC1) values were 92% and 72%. In comparison, the second principal component (PC2) values were 5% and 20% in females and males, respectively. The results of discriminant function analysis (DFA) suggested that only one (BW) of the five morphometric characters was significant in separating both sexes. Both sexes were also revealed variations in growth patterns based on the allometric analysis results. These results were expected to be used as a basis for managing the horseshoe crab population-based conservation.


2015 ◽  
Author(s):  
Tsung Fei Khang ◽  
Oi Yoon Michelle Soo ◽  
Wooi Boon Tan ◽  
Lee Hong Susan Lim

Anchors are important attachment appendages that prevent the physical dislodging of a monogenean parasite from fish host gills. Common descent and evolutionary processes have left their mark on anchor morphometry, in the form of patterns of shape and size variation useful for systematic and evolutionary studies. We used a geometric morphometric approach to explore anchor shape variation in 13 Ligophorus (Monogenea:Ancyrocephalidae) species infecting two marine mugilid (Teleostei: Mugilidae) fish hosts (Moolgarda buchanani and Liza subviridis) in the waters off West Peninsular Malaysia. Molecular sequence data from three nuclear markers: 28S rRNA, 18S rRNA and ITS1, were used to infer a maximum likelihood phylogeny to enable visualization of shape evolution in phylomorphospace. For inferring patterns of size evolution in the phylogeny, we used a size measure based on the first principal component of all pairwise Euclidean distances between landmarks. Cluster heat map and principal component analysis showed that anchor shape variation had sufficient systematic information for delimiting 12 of the 13 species. Adams' multivariate K test indicated significant correlation between anchor shape and phylogeny (p-value = 0.0001). We also discovered that characters based on anchor shaft shape, the length between inner and outer root tips and the length between inner root tip and the dent point were more phylogenetically informative than inner and outer lengths, as indicated by a maximum parsimony tree that was better resolved and had major clades congruent with those of the molecular phylogenetic tree. Continuous character mapping of size onto the inferred molecular phylogeny and Rayleigh’s test for departure from directional uniformity in each species’s landmark relative to the ancestor indicated that species infecting M. buchanani generally evolved larger and more robust anchors, while those infecting L. subviridis generally evolved smaller and more delicate anchors. Nevertheless, phylogenetic regression of anchor shape against body size and anchor size showed significant correlation (p-value = 0.02) between anchor shape and size, suggesting morphometric constraints in anchor evolution. Finally, morphological integration analysis revealed tight integration between the root and point compartments within anchors, confirming that the anchor functions as a single, fully integrated module. The present work is supported by the development of integrative analytical tools in the form of a new R package – monogeneaGM. By lowering barriers to data integration and analysis , we aim to encourage the scientific community to collect and contribute morphometric and genetic data from other Ligophorus species, which are essential for developing Ligophorus as a model system for understanding association between patterns of anchor shape size evolution and biodiversity in the Monogenea.


2016 ◽  
Vol 64 (4) ◽  
Author(s):  
Edna Judith Márquez ◽  
Natalia Restrepo-Escobar ◽  
Francisco Luis Montoya-Herrera

The endangered species Strombus gigas is a marine gastropod of significant economic importance through the Greater Caribbean region. In contrast to phenotypic plasticity, the role of genetics on shell variations in S. gigas has not been addressed so far, despite its importance in evolution, management and conservation of this species. This work used geometric morphometrics to investigate the phenotypic variation of 219 shells of S. gigas from eight sites of the Colombian Southwest Caribbean. Differences in mean size between sexes and among sites were contrasted by analysis of variance. Allometry was tested by multivariate regression and the hypothesis of common slope was contrasted by covariance multivariate analysis. Differences in the shell shape among sites were analyzed by principal component analysis. Sexual size dimorphism was not significant, whereas sexual shape dimorphism was significant and variable across sites. Differences in the shell shape among sites were concordant with genetic differences based on microsatellite data, supporting its genetic background. Besides, differences in the shell shape between populations genetically similar suggest a role of phenotypic plasticity in the morphometric variation of the shell shape. These outcomes evidence the role of genetic background and phenotypic plasticity in the shell shape of S. gigas. Thus, geometric morphometrics of shell shape may constitute a complementary tool to explore the genetic diversity of this species.


2017 ◽  
Vol 88 (18) ◽  
pp. 2055-2075 ◽  
Author(s):  
Rong Liu ◽  
Xia Guo ◽  
Qiujin Peng ◽  
Le Zhang ◽  
Terence T Lao ◽  
...  

Poor fit has become one of reasons for high non-compliance in the use of garments made of compression textiles in venous deficiency treatments. A novel methodology to categorize lower body shapes and sizes has been established via three-dimensional digital anthropometric technology in this study based on 208 Hong Kong subjects aged 40–60 years. Three new parameters were introduced to classify body shapes, namely the “A-angle” for assessing the “alignment” of lower extremities, the “cosine values of the key angle” at the turning point for below-knee shape determination, and “gradient” for above-knee shape categories. The mathematical simulation via the interpolation function was employed to explore the characteristics of shape variation trends with the involvement of dynamic interactions of both circumferences ( Cir) and heights ( Hei) of lower extremities. The clustering analysis quantitatively segmented the sample population into three stratified leg morphologies (i.e. diamond, inverted trapezoid, and balanced leg shapes) in terms of the determined anthropometric landmarks along the lower extremities, in which the C ir( s) of the brachial ( cB1), calf ( cC), and thigh ( cF) exhibited most obvious differences among the clustered lower limbs. The created stratified shape-driven sizing system and methodologies further involved the body shape classifications into the Cir-based size categories to cater for diverse body morphologies in product size selection, thus improving dimensional fitness and accurate treatment using compression textiles in practice.


2015 ◽  
Author(s):  
Tsung Fei Khang ◽  
Oi Yoon Michelle Soo ◽  
Wooi Boon Tan ◽  
Lee Hong Susan Lim

Anchors are important attachment appendages that prevent the physical dislodging of a monogenean parasite from fish host gills. Common descent and evolutionary processes have left their mark on anchor morphometry, in the form of patterns of shape and size variation useful for systematic and evolutionary studies. We used a geometric morphometric approach to explore anchor shape variation in 13 Ligophorus (Monogenea:Ancyrocephalidae) species infecting two marine mugilid (Teleostei: Mugilidae) fish hosts (Moolgarda buchanani and Liza subviridis) in the waters off West Peninsular Malaysia. Molecular sequence data from three nuclear markers: 28S rRNA, 18S rRNA and ITS1, were used to infer a maximum likelihood phylogeny to enable visualization of shape evolution in phylomorphospace. For inferring patterns of size evolution in the phylogeny, we used a size measure based on the first principal component of all pairwise Euclidean distances between landmarks. Cluster heat map and principal component analysis showed that anchor shape variation had sufficient systematic information for delimiting 12 of the 13 species. Adams' multivariate K test indicated significant correlation between anchor shape and phylogeny (p-value = 0.0001). We also discovered that characters based on anchor shaft shape, the length between inner and outer root tips and the length between inner root tip and the dent point were more phylogenetically informative than inner and outer lengths, as indicated by a maximum parsimony tree that was better resolved and had major clades congruent with those of the molecular phylogenetic tree. Continuous character mapping of size onto the inferred molecular phylogeny and Rayleigh’s test for departure from directional uniformity in each species’s landmark relative to the ancestor indicated that species infecting M. buchanani generally evolved larger and more robust anchors, while those infecting L. subviridis generally evolved smaller and more delicate anchors. Nevertheless, phylogenetic regression of anchor shape against body size and anchor size showed significant correlation (p-value = 0.02) between anchor shape and size, suggesting morphometric constraints in anchor evolution. Finally, morphological integration analysis revealed tight integration between the root and point compartments within anchors, confirming that the anchor functions as a single, fully integrated module. The present work is supported by the development of integrative analytical tools in the form of a new R package – monogeneaGM. By lowering barriers to data integration and analysis , we aim to encourage the scientific community to collect and contribute morphometric and genetic data from other Ligophorus species, which are essential for developing Ligophorus as a model system for understanding association between patterns of anchor shape size evolution and biodiversity in the Monogenea.


1990 ◽  
Vol 68 (7) ◽  
pp. 1410-1419 ◽  
Author(s):  
R. G. Foottit ◽  
M. Mackauer

Morphological variation in Cinara nigra (Wilson), found on Pinus contorta Dougl. ex Loud, throughout western North America, was characterized with the aid of univariate and multivariate statistical methods. Within-population variation in one sample collected near Edson, Alberta, was examined. Correlation and principal component analysis revealed patterns of interdependence among characters as well as patterns of size and size-related shape variation in 52 characters. To examine morphological variation between 19 geographic samples, this initial set was reduced in two steps to 49 and 32 characters, respectively; the reduction did not result in a significant loss of information content. No geographic pattern in clusters of samples was revealed either by the ordination of sample centroids or by UPGMA cluster analysis of the Mahalanobis D values. The taxonomic implications of this morphometric analysis are discussed, in particular the usefulness of various morphological attributes for species discrimination.


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