Landmark-based Geometric Morphometric Analysis Research Articles

Avialan-like brain morphology in Sinovenator (Troodontidae, Theropoda)

Many modifications to the skull and brain anatomy occurred along the lineage encompassing non-avialan theropod dinosaurs and modern birds. Anatomical changes to the endocranium include an enlarged endocranial cavity, relatively larger optic lobes that imply elevated visual acuity, and proportionately smaller olfactory bulbs that suggest reduced olfactory capacity. Here, we use micro-computed tomographic (μCT) imaging to reconstruct the endocranium and its neuroanatomical features from an exceptionally well-preserved skull of Sinovenator changii (Troodontidae, Theropoda). While its overall morphology resembles the typical endocranium of other troodontids, Sinovenator also exhibits unique endocranial features that are similar to other paravian taxa and non-maniraptoran theropods. Landmark-based geometric morphometric analysis on endocranial shape of non-avialan and avialan dinosaurs points to the overall brain morphology of Sinovenator most closely resembling that of Archaeopteryx, thus indicating acquisition of avialan-grade brain morphology in troodontids and wide existence of such architecture in Maniraptora.

Macroscopic differences in adult human femora are linked to body mass index.

Bone functional adaptation is routinely invoked to interpret skeletal morphology despite ongoing debate regarding the limits of the bone response to mechanical stimuli. The wide variation in human body mass presents an opportunity to explore the relationship between mechanical load and skeletal response in weight-bearing elements. Here, we examine variation in femoral macroscopic morphology as a function of body mass index (BMI), which is used as a metric of load history. A sample of 80 femora (40 female; 40 male) from recent modern humans was selected from the Texas State University Donated Skeletal Collection. Femora were imaged using x-ray computed tomography (voxel size ~0.5 mm), and segmented to produce surface models. Landmark-based geometric morphometric analyses based on the Coherent Point Drift algorithm were conducted to quantify shape. Principal components analyses were used to summarize shape variation, and component scores were regressed on BMI. Within the male sample, increased BMI was associated with a mediolaterally expanded femoral shaft, as well as increased neck-shaft angle and decreased femoral neck anteversion angle. No statistically significant relationships between shape and BMI were found in the female sample. While mechanical stimulus has traditionally been applied to changes in long bong diaphyseal shape it appears that bone functional adaptation may also result in fundamental changes in the shape of skeletal elements.

Geometric morphometric analysis of Pleuronectiformes vertebrae: A new tool to identify archaeological fish remains?

Flatfish (Pleuronectiformes) vertebrae are difficult to identify to species due to the lack of diagnostic features. This has resulted in a lack of understanding of the species abundances across archaeological sites, hindering interpretations of historical fisheries in the North Sea area. We use a new approach, utilising a combined 2D landmark-based geometric morphometric analysis as an objective and non-destructive method for species identification of flatfish vertebrae from the North Sea area. Modern specimens were used as a reference to describe the morphological variation between taxa using principal component analysis (PCA) and to trial an automated classification using linear discriminant analysis. Although there is limited distinction between taxa using PCAs, the classification shows high accuracies, indicating that flatfish species identifications using geometric morphometrics are possible. Bone samples (n = 105) from two archaeological sites in the United Kingdom and France were analysed using this approach and their identifications were verified using collagen peptide mass fingerprinting. The success rate of species identification was usually less than 50%, indicating that this technique has limited applicability due to preservation/fragmentation of archaeological fish bone. Nonetheless, this could prove a valuable tool for modern and non-fragmented samples. Furthermore, the technique applied in this study can be easily adapted to work on other landmark datasets.

Variation in shell morphology in the fossil freshwater gastropod Tanousia subovata (SETTEPASSI 1965) from the Mercure Basin (Middle Pleistocene, southern Italy): Distinct taxa or ecophenotypic variation? (Gastropoda Prosobranchia: Hydrobiidae)

The study of the shell plasticity of the extinct Hydrobiidae Tanousia subovata (settePassI 1965) resulted in a better understanding of the relationships between the shape of the organisms and the environment that influenced their life. Three populations, from distinct sections of the lacustrine Middle Pleistocene Mercure Basin (Basilicata-Calabria, southern Italy), have been investigated, using a landmark-based geometric morphometric analysis to quantify the morphological variability. Morphometric data and data coming from independent proxies (such as lithology and other fossils), already published on the studied basin, have been taken into account. Results have been interpreted to discriminate between internal and external factors influencing the shape of the shell. The geometric morphometric method proved useful to reveal some morphological variations between the three populations, which, following the comparisons with palaeoenvironmental data and with the literature appear to result from ecological or maybe chronological factors rather than indicating distinct species.

The dentition of the extinct megamouth shark, Megachasma applegatei (Lamniformes: Megachasmidae), from southern California, USA, based on geometric morphometrics

Megachasma applegatei is an extinct megamouth shark (Lamniformes: Megachasmidae) commonly found in late Oligocene‒early Miocene marine deposits of the western USA, that is known only from isolated teeth exhibiting odontaspidid tooth design. In this study, we investigated the tooth morphometry of the extant megamouth shark (Megachasma pelagios) and smalltooth sandtiger (Odontaspis ferox: Odontaspididae) to aid in the reconstruction of the dentition of M. applegatei based on the tooth morphometry of 207 isolated fossil teeth from the lower Miocene Jewett Sand of southern California. Our landmark-based geometric morphometric analyses show that M. applegatei not only possesses a wider morphological range of teeth than M. pelagios, but also has morphological variation that can be corresponded to different tooth types in O. ferox, forming a unique heterodont dentition typical for macrophagous lamniform sharks known as the ‘lamnoid tooth pattern’. Therefore, our study suggests that the dentition of M. applegatei could have also exhibited the lamnoid tooth pattern. In order to reconstruct the dentition of M. applegatei, specific tooth specimens plotted on the morphospace of M. applegatei were selected by identifying teeth of specific tooth types in the corresponding morphospaces of M. pelagios and O. ferox. However, because the total number of teeth per each dental series cannot be ascertained, we generated three sets of reconstructed dentition for M. applegatei. The first set modeled the dentition of O. ferox, the second set representing an intermediate form between O. ferox and M. pelagios, and the third set mimicking the dentition of M. pelagios, with the assumption that the true dental pattern for M. applegatei lies somewhere between the first and third tooth sets, possibly close to the second set. This study represents the first case of using geometric morphometrics to reconstruct the dentition of an extinct shark.

Effects of obesity on talar micro- and macro-morphology.

The addition of information regarding obesity status to the forensic anthropological biological profile could significantly contribute to the identification of human skeletal remains since over 40% of the U.S. adult population is currently obese. This study examines the differences in talar shape and trabecular bone structure between obese and non-obese individuals. A sample of 20 obese and 20 non-obese divided evenly by sex was selected from the Texas State University Donated Skeletal Collection. Tali were imaged using x-ray computed tomography (voxel size: 28-38.7μm). Image stacks were processed to produce binary images as well as trabecular thickness and spacing maps. Landmark-based geometric morphometric analyses were conducted to quantify shape variation. Shape coordinates were used to locate 100 geometrically homologous volumes of interest within each talus. Bone volume fraction, trabecular thickness, and trabecular spacing were extracted at each volume of interest. Within each sex, a one-way ANCOVA was used to determine if significant differences exist between obese and non-obese individuals in trabecular bone after controlling for age. The size of the talus as well as subtle aspects of shape were found to distinguish the sexes. The results further indicate that bone volume fraction significantly differs between obese and non-obese males. In females, bone volume fraction is correlated with age but does not differ between obese and non-obese. The study demonstrates that bone microstructure is a promising approach to estimating body mass or body mass index category but age effects diminish the potential for the talus to be used alone.

Intraspecific variation in wing geometry among Tabanus rubidus (Diptera: Tabanidae) populations in Thailand

Tabanus rubidus (Wiedemann, 1821) (Diptera: Tabanidae) is a hematophagous insect of veterinary and medical importance and is the predominant Tabanus spp. in Thailand. It is a potential mechanical vector of Trypanosoma evansi, which causes surra in domestic and wild animals. Wing geometric morphometrics is widely used as morphological markers for species identification and to assess the insect population structure. Herein, we investigated the intraspecific variation in wing geometry among T. rubidus populations in Thailand using landmark-based geometric morphometric analysis. Tabanus rubidus females were collected from five populations in four geographical regions in Thailand. The left wings of 240 specimens were removed and digitized using 22 landmarks for analysis. While wing size variations were found between some populations, wing shape variations were detected in all. These intraspecific variations in T. rubidus populations indicate an adaptive response to the local environmental conditions.

Sauropod Trackway Morphometrics: An Exploratory Study Using Highway A16 Excavation at the Courtedoux-Tchâfouè Track Site (Late Jurassic, NW Switzerland)

Ichnogeneric classification of sauropod trackways is determined using qualitative and quantitative descriptions of morphological parameters. More recently, the validity of several of these parameters has been called into question (e.g., trackway gauge). This paper aims to test traditional and more novel landmark-based geometric morphometric (GM) analysis to describe sauropod tracks and trackways. The Courtedoux-Tchâfouè (TCH) tracksite, in NW Switzerland, has been used as a test site because it hosted several Late Jurassic sauropod track-bearing levels, over a short time period (∼40 ka), creating a time capsule of sauropod activity. Exploratory statistical analyses suggest that the TCH trackway dataset can be partitioned into clusters based on trackway parameters (e.g., width of pes angulation pattern/pes length) that demonstrate differences between trackways. Nevertheless, clustering reflected a moderate degree of intercluster similarity and a continuum in TCH trackway morphologies. The GM analysis of TCH pes impressions, from several trackways, indicates a similar morphotype and did not significantly differentiate pes tracks from various stratigraphic levels. Currently, the results indicate that neither linear nor landmark-based geometric morphometric methods strongly segregate tracks at TCH nor show a time-control (i.e., via stratigraphic level) over the short interval studied. The methods reinforce that sauropod pes impression shape is conservative and that combining morphological methods to be inclusive of sauropod trackway data is important. The TCH site demonstrates that variability may reflect morphological continuums and behavioural factors and does not unambiguously differentiate unique sauropod trackmakers. More exploration on the minimum number of trackway parameters as predictors of sauropod ichnotaxonomy is needed. Integrating complementary techniques will provide more insight and practical means of identification and delineation of sauropod tracks and their trackways.

The Central Ohio Archaeological Digitization Survey

AbstractSignificant parts of the archaeological record are in private hands, including those of responsible and responsive stewards (RRS). This is not necessarily a bad thing. The Central Ohio Archaeological Digitization Survey (COADS) engages RRS in collaborative study of central Ohio prehistory. COADS leverages the mass of RRS data constructively to add depth and breadth to a regional archaeological record. We recorded over 12,000 diagnostic points and about 5,000 other stone tools from 32 RRS collections. All were scanned as two-dimensional (2D) images, and a sample as three-dimensional (3D) models for landmark-based geometric morphometric (LGM) analysis and GIS analysis of prehistoric land use. The resulting dataset is >4.7 times the number of diagnostics recorded in the Ohio SHPO database for the region, shedding new light on land use and tool use over millennia. In addition to academic research, COADS creates an accessible collection of 3D models available to RRS colleagues and to society at large. This reciprocal sharing mutually benefits professionals and the RRS community. Professionals are not the only ones who research the cultural past; the more and better we collaborate with RRS and others with legitimate interests, the better our common understanding of that past.

Wing Morphometric and DNA Barcoding Analysis of Two Different Public Health Important Anopheles Mosquito Species

Accurate identification and bio-ecology of mosquito vectors is paramount importance in several respects including the development of species-specific vector control strategies. In the current study, we explored two different advance tools such as Geometric morphometric (GM) and DNA barcoding analysis, to supplement morpho-taxonomy based identification of malaria vectors. In landmark-based GM analysis, the pattern of wing shape was examined and we noticed a clear variation in their shape among different Anopheles species. Similarly, in the DNA barcoding studies, the phylogenetic analysis based upon the marker genes such as COI, Cytb and D3 region of 28s rDNA gene sequences were carried out. The neighbour joining tree was formed by distinctive conspecific clusters illustrating genetic variation among different group of Anopheles species. Further, genetic exchange among different Anopheline populations was analysed by considering the COI gene sequences. In the gene flow study, the frequent genetic divergence as well as gene exchange among Anopheles stephensi mosquito populations was observed. Our findings suggested that GM analysis of the wing shape along with DNA barcoding approach can effectively be used together for accurate identification of mosquito vectors including Anopheles stephensi and Anopheles barbirostris.

Wing morphometrics as a tool for the identification of forensic important Lucilia spp. (Diptera: Calliphoridae)

Blow flies of the genera Lucilia Robineau-Desvoidy (Diptera: Calliphoridae) are considered forensically important species across several regions of the world. Due to the similarity of adults, especially females, the usual methods based on morphology or even molecular techniques can experience some limitations; therefore, alternative or supportive tools are required. Recently, the landmark-based geometric morphometric analysis has been applied to discriminate many insects on genus and species level. Herein, we focus on wing morphometric analysis as a tool in classifying five species of Lucilia; three species from Thailand - L. cuprina (Wiedemann, 1830), L. porphyrina (Walker, 1856) and L. sinensis Aubertin, 1933; and two species from Switzerland - L. caesar (Linnaeus, 1758) and L. illustris (Meigen, 1826). Canonical variate analysis of 233 right wings showed four overlapping clusters of L. cuprina, L. sinensis, L. caesar, and L. illustris with one distinct cluster of L. porphyrina. Eighty-eight to 100 percent of correct classification was achieved, with an UPGMA dendrogram analysis revealing clear-cut branch and sub-branch of five species determined. Results from this study suggested that wing morphometric analysis is a useful tool for the identification of adult Lucilia spp.

Wing shape analysis on some species of Terellia serratulae (L., 1758) group (Diptera: Tephritidae) based on geometric morphometric analysis

Tephritidae (fruit flies) is one of the most important Diptera families and includes more than 200 pest species. Some species in this family have a high level of similarity and are difficult to distinguish morphologically. In this study, landmark-based geometric morphometric analysis using wing images was performed on three members of the Terellia (sensu stricto) serratulae group in order to distinguish Terellia fuscicornis (Loew, 1844), Terellia nigripalpis Hendel, 1927, and Terellia serratulae (L., 1758). Specimens of the T. fuscicornis , T. nigripalpis and T. serratulae used in the study were collected from three provinces (İzmir, Kahramanmaraş and Adıyaman) of Turkey between 2016 and 2018. The geometric morphometric analysis of the wings, using fifteen landmarks, indicated significant differences in the wing shapes of each species, separating them successfully into distinct groups. CVA (canonical variate analysis) results based on the wing shapes strongly support the existence of taxonomically three different species. The reidentification accuracies were high, and wing shape discriminated three species of Terellia with over 87% accuracy. Finally, we concluded that landmark-based geometric morphometric analysis could be a powerful tool to identify Terellia spp.

Wing morphometrics of medically and forensically important muscid flies (Diptera: Muscidae)

Many muscid flies (Diptera: Muscidae) are well-known as medical, veterinary, and forensically significant insects, thus correct species identification is critically important before applying for fly control and determining a minimal postmortem interval (PMImin) in forensic investigations. Limited in taxonomic keys and taxonomists, as well as scanty in advanced molecular laboratories lead to difficulty in identification of muscids. To date, a landmark-based geometric morphometric analysis of wings has proven to be a promising alternative technique for identifying many insect species. Herein, we assessed wing morphometric analysis for identification of six medically and forensically important muscids, namely Musca domestica Linnaeus, Musca pattoni Austen, Musca ventrosa Wiedemann, Hydrotaea chalcogaster (Wiedemann), Hydrotaea spinigera Stein, and Dichaetomyia quadrata (Wiedemann).A total of 302 right wing images were digitized based on 15 homologous landmarks and wing shape variation among genera and species was analyzed using canonical variate analysis, whereas sexual shape dimorphism of M. domestica, M. ventrosa, and D. quadrata was analyzed using discriminant function analysis. The cross-validation revealed a relatively high percentage of correct classification in most species, ranging from 86.4% to 100%, except for M. pattoni, being 67.5%. Misidentifications were mainly due to cross-pairings of the genus Musca; M. domestica VS M. pattoni VS M. ventrosa. The accuracy of classification using cross-validation test demonstrated that wing shape can be used to evaluate muscid flies at the genus- and species-level, and separate sexes of the three species analyzed, with a high reliability. This study sheds light on genus, species, and sex discrimination of six muscid species that have been approached using wing morphometric analysis.

Molecular and morphological evidence for a unified, inclusive Sinotaia quadrata (Caenogastropoda: Viviparidae: Bellamyinae)

ABSTRACT The taxonomy of species in the caenogastropod genus Sinotaia (Viviparidae: Bellamyinae) has been a complex and controversial issue since the 19th century. Sinotaia quadrata, the type species of Sinotaia, comprises many named forms and transitions between them, and the taxonomic validity of some species similar to S. quadrata also requires clarification. To clarify relationships in this common and significant member of the freshwater benthos, we reconstructed a phylogeny for species related to S. quadrata based on the 16S rRNA and cytochrome c oxidase subunit I genes to test which classifications are robust using modern data and interpretation. We also compared the shell outline morphology of type material of most species in the genus Sinotaia from the original literature. The combination of phylogenetic and shape variance data suggests that seven currently recognized species of Sinotaia should be synonymized with S. quadrata. We used microsatellite markers and landmark-based geometric morphometric analysis to examine the genetic differentiation and shell shape variation of S. quadrata populations in both China and Japan. Genetic and shape variations were not congruent, suggesting that minor variations in shell shape do not indicate distinct Sinotaia species. Shell shape variation shows no clear separations and shows environmental plasticity. Using data on molecular phylogenetics, genetic diversity and shell morphology, we provide a more inclusive species concept for S. quadrata. This provides a basis to formally revise this taxon and the seven closely related nominal species that are widely distributed in China and East Asia.

Landmark-based geometric morphometric analysis of wing size and wing shape among Aedes albopictus (Skuse, 1894) populations in Turkey.

Aedes albopictus (Skuse, 1894) has a widespread distribution that includes both temperate and tropical climates. It is a potential vector of several important worldwide arboviruses, including chikungunya, zika, and dengue, and its geographical distribution expands rapidly. Despite its vectorial importance, the bioecological features of this species in newly established environments are still not very well known. Thus, this study investigated phenotypic variations among Ae. albopictus populations from different regions in Turkey. This is the first comparative morphological study of Ae. albopictus populations in Turkey. The procrustes distances phenogram derived from wing data indicates that the shape differences among some populations and the population from the Aegean coast differ from the Black Sea populations. Size differences were also detected between some populations.

Evaluation of fluctuating asymmetry and sexual dimorphism of Channa striata using landmark-based geometric morphometric analysis from Agusan Marsh and Lake Mainit in Caraga Region, Philippines

Abstract. Saura EBD, Falcasantos GC, Andante RJM, Munda LC, Alimorong MM, Hernando BJ. 2021. Evaluation of fluctuating asymmetry and sexual dimorphism of Channa striata using landmark-based geometric morphometric analysis from Agusan Marsh and Lake Mainit in Caraga Region, Philippines. Nusantara Bioscience 13: 100-110. Evaluation was conducted to determine the impact of ecological condition to Channa striata using fluctuating asymmetry (FA) employing the landmark-based geometric morphometric analysis, using TPS software, SAGE, PAST-Hotellings Test, including Physico-chemical analysis, cyanide and four base metals. Results of Physico-chemical analysis of the two habitats showed Agusan marsh with low oxygen level (3.37-4.55) and high in Iron and TDS as compared to DENR Standards. The statistical results showed high variations (p < 0.0001) on left and right-side having percentage of 79.22% in Agusan Marsh and 72.35% in Lake Mainit which is relatively high Fluctuating Asymmetry. In terms of sex, Agusan marsh had 84.27% and 85.41% FA in males and females while Lake Mainit having 85.12% and 80.89% in males and females. The fairly similar percentage of Fluctuating Asymmetry confirms no sexual dimorphism and no shape differences between male and female, and no peculiar characters to distinguished between sexes based on the 17 landmark points. Present study concluded that FA observed in the snout tip was due to breeding behavior, the landmark points in cephalic, pectoral, and caudal region were associated with burrowing and mobility factors within the lateral line system in these fishes which thrive in high turbid habitat and low oxygen. Furthermore, it was found that the level of FA tends to increase in disturbed environs.

Dimorfismo sexual en la geometría alar de Musca domestica L. (Diptera: Muscidae) de Colombia

Sexual dimorphism in flies has been evidenced in classical morphological characters, but little is known about the differentiation in wing geometry, a multivariate character highly controlled at the genetic level that influences the flight and impacts its life history and can be analyzed through geometric morphometrics. Here, we evaluated sexual dimorphism in the wing geometry of Musca domestica L., a cosmopolitan synanthropic fly. Specimens from Colombia were used for wing mounting, photography, and landmark-based geometric morphometric analysis. We found significant differences between male and female specimens in wing size and shape. Particularly, cross-validated classification based on wing shape resulted in high scores (90%) of correct sex attribution. The influence of wing geometry differences on the flight performance and life history in this species remains unknown.

A new fanged frog in the Limnonectes kuhlii complex (Anura: Dicroglossidae) from northeastern Cambodia.

The Limnonectes kuhlii complex is a group of morphologically similar species of fanged frogs distributed across much of mainland and insular Southeast Asia. Many new species in this complex have been described in recent years, primarily on the basis of mitochondrial DNA divergence corroborated by differences in linear measurements and qualitative characters. Males in this species complex develop enlarged heads at sexual maturity, but the degree of head enlargement varies among mature males, even within the same population. We evaluated the utility of body length (snout-vent length minus head length) in descriptive statistics and in size-adjusting measurements for traditional morphometric analysis, as well as a landmark-based geometric morphometric analysis of male head shape, in Indochinese species of the L. kuhlii complex. The analyses supported quantitative and qualitative morphological distinction of a divergent mitochondrial lineage of the L. kuhlii complex in northeastern Cambodia, and the lineage is described as a new species. Limnonectes fastigatus sp. nov. differs from its closest relatives and from geographically proximate members of the complex by having the combination of elongated, slender odontoids; nuptial pads on the first finger; immaculate belly; significantly different body length-adjusted measurements in both sexes; and a significantly different male head shape. The new species is the only member of the L. kuhlii complex known from Cambodia.

Body forms in sharks (Chondrichthyes: Elasmobranchii) and their functional, ecological, and evolutionary implications

Sharks are among the oldest vertebrate lineages in which their success has been attributed to their diversity in body shape and locomotor design. In this study, we investigated the diversity of body forms in extant sharks using landmark-based geometric morphometric analyses on nearly all the known (ca. 470) extant sharks. We ran three different analyses: the ‘full body,' ‘precaudal body,’ and ‘caudal fin' analyses. Our study suggests that there are two basic body forms in sharks, a ‘shallow-bodied’ form (Group A) and ‘deep-bodied’ form (Group B), where all sharks essentially have one basic caudal fin design of a heterocercal tail despite some specializations. We found that swimming modes in sharks are highly correlated with body forms where Group A sharks are predominantly anguilliform swimmers and Group B sharks are represented by carangiform and thunniform swimmers. The majority of Group A sharks are found to be benthic whereas pelagic forms are relatively common among Group B sharks. Each of the two superorders of sharks, Squalomorphii and Galeomorphii, must have gone through complex evolutionary history where each superorder contains both Group A sharks and Group B sharks, possibly involving parallel evolution from one group to the other or at least one episode of evolutionary reversal.

An appraisal of subspecific classification of Apis mellifera L. in parts of West and Central Africa through landmark-based geometric morphometric analysis of forewings

To appraise the subspecific classification of Apis mellifera L. in West and Central Africa, 1663 workers from 175 colonies from 44 localities, were sampled throughout Nigeria and parts of Niger, Cameroon and Chad. The samples were analysed with reference subspecies (A. m. adansonii (N = 12), A. m. jemenitica (N = 14) and A. m. scutellata (N = 12)), using geometric morphometric analysis, based on 19 landmarks on the left forewings of workers. The analysis allowed separating size and shape of the wing. Hierarchical cluster analysis followed by stepwise discriminant analysis (DA) grouped the colonies into two morphoclusters with a cross-validation classification rate of 96.6%. ANOVA revealed a significant difference (p < 0.0005) between the unknown colonies and either of A. m. jemenitica and A. m. scutellata but an insignificant difference (p > 0.05) between them and A. m. adansonii in respect of size. MANOVA revealed a significant difference (p < 0.0005) between the unknown colonies and each of the reference subspecies regarding shape or form (shape + size). All the colonies formed one cluster in a PCA of shape and form, respectively. Based on shape, DA assigned 46.02% and 2.84% of the unknown colonies to A. m. scutellata and A. m. adansonii, respectively, with a posterior probability of ≥95%. However, when shape and size were combined, DA assigned 28.40%, 21.02% and 10.23% of the unknown colonies to A. m. adansonii, A. m. scutellata and A. m. jemenitica, respectively, with a posterior probability of ≥95%. Thus, though this classification is not definitive, it suggests that the unknown colonies are morphologically closer to adansonii and scutellata than jemenitica. However, in order to avoid further confusion in the nomenclature of the honey bees of this region, it is recommended that A. m. adansonii could be retained as their sole subspecific name, pending further studies.