Automatic determination of landmark coordinates for honey bee forewing venation using a new MATLAB-based tool

Abstract

In this study, a novel and free-to-use MATLAB-based tool (WingMarks) is presented, aimed at facilitating the geometric morphometric analysis of forewing venation through an automatic recognition of vein junctions. Firstly, the ability of the new software to analyze wing images obtained by different optical equipment was evaluated. Even when a low-end USB-microscope was used for image collection, it reached 100% precision in the automatic detection of the landmarks for 74% of the samples, and most of failures corresponded to a single point and were easily corrected. The measurement error of WingMarks software was studied through repeated analysis of the same wing image, evincing that landmark determination was highly repeatable, even higher than that of widely used tpsDig manual software. In addition, a field test with 720 specimens from three subspecies (A. m. iberiensis, A. m. ligustica, and A. m. carnica) and from Buckfast hybrid, collected from 90 different colonies, was conducted. In conjunction with MorphoJ, the coordinates of the vein junctions extracted by the program led to an accurate classification of the specimens, confirmed by canonical variate analysis methods. WingMarks software can thus be deemed as a versatile, precise and accurate tool for the automatic recognition of Apis mellifera wing vein junctions, facilitating the identification of bee genetic diversity using geometric morphometrics. The program is available under Creative Commons license and can be easily adapted to different insect species.

APIS MELLIFERA EN EL ALTIPLANO CENTRAL DEL ECUADOR: africanización, Varroa destructor, caracteres conductuales y producción melífera

“…Estas limitaciones y la continua reducción de los costos de la tecnología de biología molecular, convirtieron a los sistemas de reconocimiento de ADN en una alternativa más atractiva que la morfometría (Francoy et al, 2008). A pesar de esto, los métodos morfométricos se siguieron desarrollando y avanzando (Ángel-Beamonte et al, 2018).…”

“…Se realizaron varios intentos para simplificar la determinación morfológica, como es el caso de Francoy et al, (2006) quienes redujeron el número de caracteres y la utilización de la célula radial de ala (Figura 11), o emplear un programa informático automatizado diseñado específicamente para las mediciones morfométricas (Ángel-Beamonte et al, 2018;Baylac et al, 2008;Nawrocka et al, 2018;Tofilski 2004Tofilski , 2008. La información que describe la forma en estudio puede ser analizada de diversas maneras: análisis exploratorios, de componentes principales (CP), de variables canónicas (AVC), de deformación relativa, análisis multivariado de varianza (MANOVA), regresiones multivariadas y pruebas no paramétricas (Slice 2007;Zelditch 2004), para el caso de Apis mellifera, mediante un análisis de variables canónicas se pueden agrupar individuos de cada una de las subespecies, para luego analizar y clasificar muestras desconocidas en base a los patrones de variación de las alas (Porrini 2016).…”

“…En el análisis morfométrico geométrico de la venación de las alas, un programa de uso frecuente es tpsDig (Rohlf y Bookstein 2003), que requiere el trazado manual de todas las intersecciones de las venas. La principal ventaja de este software es su flexibilidad (Ángel-Beamonte et al, 2018).…”

Honey bee (Apis mellifera) wing images: a tool for identification and conservation

“…On the other hand, if a wing image is available, it can be reanalyzed, and missing or incompatible landmarks can be determined. In addition, the wing images can be used to determine the landmarks automatically [ 35 , 51 , 52 ].…”

Monthly Changes in Honey Bee Forewings Estimated Using Geometric Morphometrics

“…It had been based on the cubital index (Alpatov, 1948;Goetze, 1959), which is a proportion of two vein lengths, but later the angles between wing vein intersections were included in the measurements (DuPraw, 1965). Recently, the wings have been described according to the coordinates of landmarks located in forewing vein intersections (Francoy et al, 2008;Tofilski, 2008;Barour & Baylac, 2016;Ángel-Beamonte et al, 2018;Bustamante et al, 2020;Dukku & Danailu, 2020;). This method, called geometric morphometrics, has proven to be effective in the discrimination of honey bee subspecies (Gerula et al, 2009) and lineages (Nawrocka et al, 2017).…”