De Luna, E. 2022.

 Taxonomy of Hedwigia filiformis (Bryopsida: Hedwigiaceae) with the restitution of the confounded identity of Hedwigia integrifolia. Acta Botanica Mexicana 129: e2080.

Abstract

Background and Aims: Hedwigia integrifolia is still conflated with Hedwigidium imberbe, despite previous distinction of these two species. This paper offers clarification of the taxonomic status of Hedwigia integrifolia, as a synonym of H. filiformis. The latter name is re-established only for the species characterized by filamentous pseudoparaphyllia, leaf cells with peltate papillae, and perichaetial leaves ciliate. 

Methods: Protologues, specimens of Hedwigia worldwide from several herbaria, and personal collections were studied to evaluate the taxonomic and nomenclatural status of H. integrifolia, along with the similar species Hedwigia filiformis. Anatomical observations were recorded of pseudoparaphyllia, leaf cell papillae, and capsule neck stomata. 

Key results: My examination of numerous Hedwigia specimens worldwide led to the conclusion that Hedwigia integrifolia is a heterotypic synonym of Hedwigia filiformis. For the correct identification of Hedwigia filiformis, a morphological description and illustrations are provided for this species, so far known to occur in Canada, the USA, Mexico, Italy, Japan and South Korea.

Conclusions: Hedwigia filiformis differs from other species in Hedwigia mostly by its slender sympodial branches, short ovate leaves with revolute margins, the very short hyaline leaf acumina, and the short elliptical apical cell.


Figure 3: Morphological features of Hedwigia filiformis (Michx.) P. Beauv. A. slender sympodial stems and branches; B. leaves appressed when dry; C. detail of leaves showing the hyaline part very short. (A-C, from De Luna 2516, Mexico, Veracruz (XAL)); D-H. leaf apices acute to short acuminate, with a very short hyaline part. The upper leaf cells are subquadrate, and the apical cell is short elliptic. (D, from Macoun s.n., 1893, Canada, Ontario, “Canadian Musci 615” (FH); E, from Small s.n., 1892, USA, North Carolina (DUKE); F, from Anderson 2403, USA, North Carolina (DUKE); G, from Churchill 9469, USA, Kansas (DUKE); H, from Anderson 20616, USA, New York (DUKE). 


Gregorio-Cipriano, R., E. De Luna y D. González. 2022.

An assay for the quantification of pathogenicity and virulence of two strains of Podosphaera xanthii (Erysiphaceae) on different hosts from digital images. SYDOWIA 74: 277-285.

http://www.sydowia.at/syd74/T19-Gregorio-Cipriano-3002.pdf

DOI: https://doi.org/10.12905/0380.sydowia74-2022-0277

Abstract

The predominant species of powdery mildew in the Cucurbitaceae is Podosphaera xanthii. However, there is little information on the epidemiology of this disease in Mexico despite its importance. As a first assay, we explore the applicability of a quantitative technique to estimate differences in the severity of disease caused by P. xanthii on leaves of Cucurbitaceae. We obtained two samples from different hosts: cultivated (Cucurbita pepo) and wild (C. radicans) cucurbits. Conidia were inoculated onto the leaves of growing plants of seven cucurbit species. We used the ImageJ program to quantify the infected area for each leaf as the sum of several polygons. The severity of the infection was calculated as the percentage of the infected foliar area. The two inocula of P. xanthii were pathogenic in five of seven inoculated cucurbits. Our analyses of variance to compare the variation of the percentage values among susceptible hosts revealed different levels of severity. This result indicates that this is a promising method to quantitatively compare differences in disease severity of different strains or hosts of powdery mildews. 

Keywords: cucurbits, image analysis, infection percentage, powdery mildew, Ascomycota.



De Luna, E. 2022.

Lectotypification, taxonomy, and distribution of Braunia plicata (Hedwigiaceae) in South America and Mexico. PHYTOTAXA 532: 101-106. 
Abstract:  
Diagnosis and illustrations are given for Braunia plicata (Mitt.) A. Jaeger., and lectotypes for two names are designated. One of Bridges specimens (Bridges s. n.) located at BM hb-Hooker is the lectotype for B. plicata. A duplicate of Pringle 15171 at P hb-Cardot is the lectotype for B. plicata var canescens Card. This name is retained as synonym of B. plicata. The worldwide distribution of the species is documented in Bolivia, Peru, and Mexico. 

Keywords: Hedwigiales, Braunia, lectotypes, mosses, nomenclature, Bryophytes



Ariza-Marín, E. R. y E. De Luna. 2022.

Morphometric analyses of sexual dimorphism in sound-emitting structures in adults of the bess beetle Vindex agnoscendus (Coleoptera: Passalidae). ZOOLOGY xxxx.

DOI: https://doi.org/10.1016/j.zool.2021.125992 

PDF: https://authors.elsevier.com/a/1eelH3MhxMd8am

Abstract

In insects, the sexually dimorphic body size, color, and horns are very conspicuous. Other not so obvious characteristics, such as behavioral traits related to reproduction, are also dimorphic (courtship dances and sounds). Among these, the stridulation, stridulatory apparatus, and hearing systems could also be different between sexes. Passalids are subsocial beetles with acoustic communication in the interactions of larvae-adult and adult-adult. Most of the species do not have morphological traits with sexual dimorphism, but sounds are dimorphic under reproductive and aggression contexts. We studied sexual dimorphism in the stridulation organs (plectrum) in Vindex agnoscendus (Percheron) as an important step towards understanding its functioning. We acquired SEM micrographs of the plectrum for 14 specimens per sex, for measuring size, density and shape of the spines. We performed traditional and geometric morphometric analyses to test for sexual differences in the spines of three zones (Z1-Z3) of the plectrum. Allometric analyses showed spine variation is not related to body size in either sex. Our univariate and multivariate analyses uncovered sexual dimorphism in spine size (length and width of spines), spine density (distance between spines and number of spines), and spine shape (landmark coordinates). Spines were wider in males than in females in the apical zone (Z1). The spines were further apart in females than in males in two zones (Z1, Z2) and the spine numbers were higher in females than in males in the apical zone (Z1). The shape of spines was different between sexes in two zones (Z1, Z2). Moreover, our disparity analyses showed different variability patterns in size and density of spines. Variability of spine shape was similar between sexes, and variability of spine density was higher in females than in males, while for spine size it was higher in males than in females. These findings for the plectrum suggest further research for sexual dimorphism in the pars stridens and acoustic signals, and for the possible roles of natural and sexual selection in the patterns of variability of spines.

Keywords

Bess beetles, Geometric morphometry, Stridulatory apparatus, Sexual dimorphism, Traditional morphometry.

De Luna E. 2021

A synopsis of Braunia (Hedwigiaceae, Bryopsida) in Mexico, with the lectotypification of Braunia andrieuxii. ACTA BOTANICA MEXICANA 128: e1950. PDF
DOI: https://doi.org/10.21829/abm128.2021.1950 
Abstract
Background and Aims: Four species of Braunia are known in Mexico: Braunia andrieuxii, B. secunda, B. squarrulosa and B. plicata. A taxonomic study of the species of Braunia in Mexico has not been undertaken before. Moreover, among several “Andrieux” specimens currently available, there is no certainty as to which particular collection is the type. 
Methods: The four species of Braunia known in Mexico and neighboring areas in the southern United States of America, Central America and the Caribbean Islands were studied together for the first time. Based on over 450 collections from several herbaria, a taxonomic treatment and a key to the species of Braunia in this geographical region are presented. 
Key results: The four species are described and illustrated. A specimen Andrieux 23 located at BM is selected as the lectotype for B. andrieuxii, with isolectotypes in the herbaria BM and NY. A key is provided for the identification of the species of Braunia in Mexico, and neighboring USA, Central America, and the Caribbean. 
Conclusions: Morphological features most likely to be informative for the distinction of the four species in Mexico are the leaf margins, leaf apices, upper leaf cells, and sporophytes. The leaf apex is hyaline and dentate only in B. plicata, while it is concolorous and entire or scabrous in the other three species of Braunia from Mexico. The upper leaf cells are quadrate to short- rectangular in B. andrieuxii and B. plicata; whereas the upper leaf cells are elongate in B. secunda and B. squarrulosa
Key words: Hedwigiales, mosses, taxonomy.




Dynamic zoomable maps are shared on line here (thanks to ZeeMaps): 

 






De Luna E. 2021

Seta length variation and the refutation of Hedwigidium = Braunia (Hedwigiaceae, Bryopsida). ACTA BOTANICA MEXICANA 128: e1810. PDF. 
Abstract: 
Background and Aims: Traditionally regarded as a monotypic genus, Hedwigidium was recently proposed to be identical to Braunia, because “… some Braunia species have a seta as short as that of Hedwigidium.” This paper offers data and analyses for a refutation of the taxonomic hypothesis that Hedwigidium = Braunia. 
Methods: Seta length measurements (n=682) were sampled in 20 species of the four genera of Hedwigiaceae to compare variation between Hedwigia (n=10), Hedwigidium (n=40), Braunia (n=614), and Pseudobraunia (n=18). Measurements were subjected to analyses of variance and multiple comparison tests, to reveal if some Braunia species have a seta as short as that of Hedwigidium, or not. 
Key results: Analyses of variance followed by Mann-Whitney pairwise tests reveal that the average seta length in Hedwigidium imberbe (0.7 mm, sd=0.21) is different from the average seta length in each of the seven Braunia species with short setae, all in the range of 2.0-2.3 mm. For the first time, the geographical distribution of Hedwigidium is documented and mapped. Literature records are verified for Europe (United Kingdom, Norway, France, Italy, and Spain), Africa (Cameroon, DR Congo, Malawi, Tanzania, Uganda, Zimbabwe, South Africa, Reunion Island, Kenya), and Southeast Asia (India, Sri Lanka, Indonesia). In the New World, Hedwigidium is confirmed for Mexico, Guatemala, El Salvador, Honduras, Costa Rica, Dominican Republic, and South America (Venezuela, Colombia, Ecuador, Peru, Bolivia, Chile, Argentina, and Brazil). 
Conclusions: The data and statistical analyses presented here refute the taxonomic conclusion proposing Hedwigidium is synonymous with Braunia. None of Braunia species has a seta as short as that of Hedwigidium. Therefore, still surviving unrefuted is the alternative hypothesis that Hedwigidium is a separate genus. Taxonomic characters important in distinguishing this genus from other genera in the Hedwigiaceae are discussed. 
 Key words: Braunia, Hedwigia, Hedwigiales, morphometrics, refutation.






Ariza-Marín, E. R. y E. De Luna. 2020.

Linear and geometric morphometric analyses of variation of the plectrum in four species of bess beetles, tribe Proculini (Coleoptera: Passalidae). ARTHROPOD STRUCTURE AND DEVELOPMENT 59: 100994. DOI: https://doi.org/10.1016/j.asd.2020.100994<>


Abstract. 
Bess beetles are sapro-xillophagous insects that inhabit decaying logs. They display sub-social behavior and acoustic communication. Adults produce sounds with an abdomino-alary stridulatory system. The sixth abdominal tergum has lateral protuberances with spines ( pars stridens ) whereas the hind wings have spines in the radial cell ( plectrum ). The potential taxonomic utility of these spines has not been studied. We evaluated variation of spines in the plectrum of adult females sampling four species of Proculini using traditional and geometric morphometric methods. We divided the plectrum into five zones to compare the density, size and shape of spines among zones and among species comparing each zone separately. Spine shape and size were quantified with 2D cartesian coordinates and four measurements from SEM micrographs. Separate univariate and multivariate analyses of variance revealed that the size, density and shape of spines is different among zones in each of the four species. Also, spine shape and size in all zones is different among species, which would imply that plectrum spines might have taxonomic utility. Additionally, disparity analyses showed that the peripheral zones have a higher variability, and the disparity values in the middle and apex zones are higher in the two species with a wide distribution range.




De Luna E. 2020.

Integrando análisis morfométricos y filogenéticos: de la sistemática fenética a la morfometría filogenética. ACTA BOTANICA MEXICANA 127: e1640.

Abstract:
Background and Aims: Quantitative methods have accumulated for the use of linear measurements and Cartesian coordinates of landmark points in analyses of morphometric variation. Unlike previous reviews, here I emphasize the theoretical bases of mathematical spaces and morphospace of a taxonomic character. The goal of this contribution is to provide conceptual elements for a basic understanding of morphometric and statistical methods useful in systematics under a phylogenetic approach.
Methods: Morphometric data are being applied in comparative biology research, using a phylogeny as a reference. In contrast, applications of morphometrics in systematics have been with the aim of phenetic grouping and distinguishing taxonomic groups with overall similarity. Under a phylogenetic approach, morphometric data can also be used for the study of taxonomic character variation, character state identity and phylogenetic inference. Taxonomic groups should be proposed from monophyletic groups discovered with phylogenetic methods. 
Key results: I review the basic morphometric theory, vector geometry, Kendall shape space, Procrustes distance, projection of tangential spaces, and construction of morphospace hypercubes. Remainders of statistical concepts useful for the application of Principal Component Analysis and Canonical Variate Analysis in systematics are presented. Particularly, I give examples and recommendations on the use of linear measurements and landmark coordinates in morphometric analyses for the identification of species, the variation of taxonomic characters and in the inference of phylogeny and classification.
Conclusions: The current broad collection of methods provides an opportunity to integrate morphometric data to discover taxic and transformational homology. This implies an epistemological change necessary to move from applications in systematics under a phenetic approach to the integration of morphometric analyses as part of phylogenetic research.

Key words: geometric morphometrics, landmarks, multivariate analysis, phylogeny, shape.



Resumen:
Antecedentes y Objetivos: Se han acumulado métodos cuantitativos para el uso de mediciones lineales y coordenadas Cartesianas de puntos en análisis de la variación morfométrica. A diferencia de revisiones previas, aquí se enfatizan las bases teóricas de los espacios matemáticos y del morfoespacio de un carácter taxonómico. El objetivo de esta revisión es suministrar elementos conceptuales para una comprensión básica de los métodos morfométricos y estadísticos útiles en la sistemática, bajo un enfoque filogenético.
Métodos: Los datos morfométricos se están aplicando en estudios de biología comparativa, usando las filogenias como referencia. En contraste, las aplicaciones de la morfometría en sistemática han sido con el objetivo de agrupar y distinguir grupos taxonómicos fenéticamente con la similitud total. Bajo un enfoque filogenético, los datos morfométricos también se pueden usar para el estudio de la variación de caracteres taxonómicos, la identidad de los estados y la inferencia de filogenias. Los grupos taxonómicos debieran ser propuestos a partir de grupos monofiléticos descubiertos con métodos filogenéticos. 
Resultados clave: Se presentan las bases de la teoría de la morfometría, geometría vectorial, el espacio de Kendall, la distancia Procrustes, proyección de espacios tangenciales y construcción de hipercubos del morfoespacio. Se revisan conceptos estadísticos útiles para la aplicación de los Análisis de Componentes Principales y los Análisis de Variables Canónicas en sistemática. Particularmente se dan recomendaciones y ejemplos sobre el uso de mediciones lineales y coordenadas de puntos en análisis morfométricos para la identificación de especies, la variación de caracteres taxonómicos y en la inferencia de filogenias y clasificación.
Conclusiones: El amplio acervo actual de métodos brinda la oportunidad de integrar los datos morfométricos para descubrir homología táxica y homología transformacional. Esto implica un cambio epistemológico necesario para transitar de aplicaciones bajo una sistemática fenética, a la integración de los análisis morfométricos como parte de la investigación filogenética.
Palabras clave: análisis multivariados, filogenia, forma, marcas, morfometría geométrica.




Chollet-Villalpando J.G. y E. De Luna. 2020

A geometric morphometric approach for disparity of the sulcus acusticus of sagitta in species of Gerreidae (Teleostei: Perciformes). ORGANISMS DIVERSITY AND EVOLUTION. 

This paper explores shape disparity in the sulcus acusticus of saccular otolith using geometric morphometric methods in selected Gerreidae species. First, multivariate linear regressions between size (CS-log-transformed) and shape were implemented to uncover allometry in the variation of the sulcus acusticus at three levels: intraspecific, intrageneric, and interspecific. Second, we assessed species disparity to investigate if differences in disparity are associated with three biologically contrasting ecological or historical processes within the family. Specifically, we asked: (1) How has disparity changed as a result of an ecological shift from marine to freshwater habitat? (2) How has disparity changed in genera with increasing taxonomic richness? and (3) How did a vicariant event across the Panama isthmus changed disparity in a pair of sister species? Our results indicate that the disparity of the sulcus acusticus shape of the single freshwater species (Eugerres mexicanus) is in the middle of the range of values of the 17 marine species compared. This suggests that the change to a freshwater environment did not influence the variability of the sulcus acusticus. In the taxonomic comparisons, as expected, disparity is lowest in the monotypic Deckertichthys, while it increases with species number in Diapterus. In the vicariant pair, the Pacific basin species (Diapterus brevirostris) has a disparity value almost twice the value than in the Atlantic taxon (D. rhombeus). It remains to be investigated if the same disparity patterns documented here are associated to marine-freshwater ecological shifts and vicariant events in other fish families.

Keywords

Fishes, Landmark data, Morphological variability, Shape disparity.

Montes de Oca AC, E. De Luna, EA Rebollar, P. Piermarini y S. Ibañez. 2019.

Morphological discontinuous variation and disparity in Lutzomyia (Tricholateralis) cruciata Coquillett (Diptera: Psychodidae) are not related to contrasting environmental factors in two biogeographical provinces. ZOOMORPHOLOGY 138: 335-348.

PDF: https://rdcu.be/bEmL5

doi: https://doi.org/10.1007/s00435-019-00450-8

Lutzomyia cruciata (Diptera: Phlebotominae) is an important Leishmania vector with wide distribution in America. However, geographical patterns of morphological variation of populations along its longitudinal and latitudinal distribution are still unknown. In this work, we quantified morphological variation and disparity in 243 specimens (females) from nine sample groups of Lu. cruciata from two biogeographical provinces in Mexico: Veracruzan Province (five groups) and Yucatan Peninsula Province (four groups). We registered two linear morphometric data of a reproductive structure (spermatheca) and one landmark configuration for wing shape. Our questions were if intraspecific morphological variation and disparity are related to contrasting environmental factors in these two provinces. First, our results from canonical variates analyses of the spermatheca and wing shape revealed more differences among groups of specimens within a biogeographic province than between. Second, our regression analyses revealed that morphometric variation is weakly related to 20 environmental variables considered for the two biogeographic provinces. Levels of morphological disparity in the spermatheca and wing shape within the two provinces are the same regardless of environmental homogeneity in the Yucatan Province or heterogeneity in the Veracruzan Province. These patterns of morphological variation and disparity weakly correlated with environmental variables suggest that intraspecific variation in Lu. cruciata is not clinal within a province. Subsequent investigations will be required to elucidate suspected correlations of local discontinuous phenotypes with genetic divergence within a biogeographical province.

Keywords

Geometric morphometrics Wing Spermatheca Phlebotominae Leishmania mexicana