Abdominal Color Pattern Research Articles

A new species of Philosina Ris, 1917 (Zygoptera) from China

A new species Philosina nigromacula Yu & Jin, 2024 is described from Sichuan, southwest China, with paratypes from Sichuan and Jiangxi, east China. The new species is generally similar to Philosina buchi Ris, 1917 but has a different abdominal color pattern. There is a strange sack-like structure on the end of the male genital ligula in P. buchi and P. nigromacula, which is described and discussed for the first time. The fragmented distribution of Philosina Ris, 1917 is also discussed as well as possible reasons for the origins of the genus. The need for protection of the small number of species contained within the unique genus Philosina is also emphasized.

Machine Learning Approach to Support Taxonomic Discrimination of Mayflies Species Based on Morphologic Data.

Artificial intelligence (AI) and machine learning (ML) offer objective solutions in the elaboration of taxonomic keys, such as the processing of large numbers of samples, aiding in the species identification, and optimizing the time required for this process. We utilized ML to study the morphological data of eight species of Americabaetis Kluge 1992, a diverse genus in South American freshwater environments. Decision trees were employed, examining specimens from the Museu de Entomologia da Universidade Federal de Viçosa (UFVB/Brazil) and literature data. Eleven morphological traits of taxonomic importance from the literature, including frontal keel, shape of the mouthparts, and abdominal color pattern, were analyzed. The decision tree obtained with the Gini algorithm effectively differentiates eight species (40% of the known species), using only eight morphological characters. Our analysis revealed distinct groups within Americabaetis alphus Lugo-Ortiz and McCafferty 1996a, based on variations in abdominal tracheae pigmentation. This study introduces a novel approach, integrating AI techniques, biological collections, and literature data for aid in the Americabaetis species identification. It provides a valuable tool for taxonomic research on contemporary and extinct mayflies.

A new species of Campsurus Eaton, 1868 (Ephemeroptera: Polymitarcyidae) from the Doce River Basin, Brazil.

The male imago of Campsurus mirim sp. nov., an integrant of the C. major species group, is described based on material from a lake at the Rio Doce basin, Southeastern Brazil. It can be distinguished from other species of the group by the following combination of characteristics: small to medium size (body 7.3 mm, forewings 6.1 mm); blackish pigments on dorsum of head widely and strongly marked in fresh material; abdominal color pattern with pale transverse dashes on terga IIIVII; posterior margin of sternum IX triangular at middle; pedestals flat with inner margin broadly rounded and with both posterolateral corners (inner and outer) approximately of the same length, both acute; penes relatively wide and large, ventrally curved on apical and with apex of main lobe slightly twisted.

Geographical variation in abdominal colour pattern in Criorhina pachymera (Egger, 1858) (Diptera: Syrphidae)

The bee-mimicking hoverfly species Criorhina pachymera shows pronounced geographical variation in abdominal colour pattern. Based on 218 records from 22 European countries, we describe six abdomen forms divided over two main groups. Group A in western, northern and central parts of Europe contains abdomen forms A1–A3 with slender pollinose bands on the third and fourth tergite. Group B in south-eastern Europe contains forms B1–B3 with broad pollinose bands. These groups are separated by the Alps and the Carpathians, such as the separation of the original distributions of the two main postglacial recolonization lineages of honey bees in Europe. As these honey bee groups differ by the width of the pollinose bands on the third to fifth tergite, Batesian mimicry can explain the group distribution of C. pachymera with slender or broad pollinose bands. The different forms of C. pachymera in both groups are categorised by the extent of orange colouration on the second and third tergite. The darkest form A1, has a widespread distribution in Europe. Intermediate bright forms A2 and A3 occur predominantly in a belt along the southern margin of the group A distribution and in Sweden. Dark form B1 and intermediate bright form B2 occur on the Balkan peninsula and in neighbouring regions. The brightest form B3, is found in Italy, Switzerland (Ticino) and Greece. There is an average increase in the extent of orange colouration on the second and third tergite with decreasing geographical latitude, making temperature a likely additional cause for the described abdominal colour variation.

Geographical variation in abdominal colour pattern in Criorhina pachymera (Egger, 1858) (Diptera: Syrphidae)

The bee-mimicking hoverfly species Criorhina pachymera shows pronounced geographical variation in abdominal colour pattern. Based on 218 records from 22 European countries, we describe six abdomen forms divided over two main groups. Group A in western, northern and central parts of Europe contains abdomen forms A1–A3 with slender pollinose bands on the third and fourth tergite. Group B in south-eastern Europe contains forms B1–B3 with broad pollinose bands. These groups are separated by the Alps and the Carpathians, such as the separation of the original distributions of the two main postglacial recolonization lineages of honey bees in Europe. As these honey bee groups differ by the width of the pollinose bands on the third to fifth tergite, Batesian mimicry can explain the group distribution of C. pachymera with slender or broad pollinose bands. The different forms of C. pachymera in both groups are categorised by the extent of orange colouration on the second and third tergite. The darkest form A1, has a widespread distribution in Europe. Intermediate bright forms A2 and A3 occur predominantly in a belt along the southern margin of the group A distribution and in Sweden. Dark form B1 and intermediate bright form B2 occur on the Balkan peninsula and in neighbouring regions. The brightest form B3, is found in Italy, Switzerland (Ticino) and Greece. There is an average increase in the extent of orange colouration on the second and third tergite with decreasing geographical latitude, making temperature a likely additional cause for the described abdominal colour variation.

Can introgression in M-lineage honey bees be detected by abdominal colour patterns?

Honey bee abdominal pigmentation is one of the most recognisable traits and it is often used by beekeepers as an indicator of M-lineage subspecies purity. However, this approach may negatively impact population diversity and is futile if there is no association between tergite colour patterns and the genetic background. To assess whether this trait can be used as a proxy for introgression proportions in M-lineage subspecies, we genotyped, with highly informative SNP assays, A. m. mellifera and A. m. iberiensis individuals displaying four different colour phenotypes. The SNP data detected highly introgressed bees exhibiting a black phenotype and, at the same time, pure or marginally introgressed bees with yellow banding patterns, in both subspecies. Despite these observations, contrary to A. m. iberiensis, in A. m. mellifera, introgression proportions revealed to be a significant predictor of abdominal pigmentation. Therefore, abdominal pigmentation could be used by A. m. mellifera conservationists to guide colony selection when genetic tools are unavailable.

Redescription of the final stadium larva of Megalestes heros Needham from Fujian, China, with discussion of the characters of genus Megalestes Selys(Odonata: Zygoptera: Synlestidae).

The final stadium larva of Megalestes heros Needham, 1930 is redescribed and illustrated in detail. It is characterized by having a long and cylindrical body, a very long prementum with two end hooks of unequal size on lateral lobe, parallel wing sheaths, long and slender legs, female ovipositor short reaching the basal third of S10, and based on a distinct abdominal color pattern. The major diagnostic characters of the larvae of the genus Megalestes are as follows: (1) body smooth and slender, with long abdomen and leaf-shaped caudal gills; (2) antenna filiform, seven-segmented,third segment longest; (3) median cleft present in median lobe of prementum; lateral lobe with two end hooks of unequal size, the inner one being longer and larger than the outer, movable hook without setae; (4) wing sheaths parallel to each other.

A new species of Platybaetis Müller-Liebenau, 1980 (Ephemeroptera: Baetidae) from Thailand, with description of the imago of Platybaetis bishopi Müller-Liebenau, 1980.

Platybaetis bishopi Müller-Liebenau, 1980 was originally described from Malaysia only at the larval stage. We provide the first description of the imaginal stage of P. bishopi based on materials from Thailand. The imago of this species can be separated from the known species by coloration of abdominal terga and coloration of wings. A new species, Platybaetis nayokensis sp. nov., is described based on male and female imagos and larvae from Thailand. The larva of this species is mainly distinguished by medium acute spines on the posterior margin of the abdominal terga and two apical setae on the glossa, which seem to be shorter than in other species. The imago can be separated by the abdominal color pattern. The larva of this genus is adapted to live on wet rocks projecting out of water; it prefers large stones near small waterfalls or areas between two large rocks in running water.

The Goblin Spider GenusKhamisiaand Its Relatives (Araneae, Oonopidae)

ABSTRACT The goblin spider genus Khamisia Saaristo and van Harten was based on a single female from Yemen characterized by large lateral extensions of the sternum that widely separate coxae II and III. Three new species, including the first known males of the genus, are described: K. hayer from the United Arab Emirates, K. atlit from Israel, and K. holmi from Kenya. All these species are united by having only two trichobothria on the palpal tibia; K. hayer has apparently been introduced into Cape Verde. Other specimens with a similarly modified sternum have been found in Africa, Madagascar, and the Virgin Islands, but differ in having the normal set of three trichobothria on the palpal tibia. The new genus Khamisina is established for three new species that also differ in having an abdominal color pattern, a punctate sternum, and uniquely shaped cheliceral setae: K. kivu from DR Congo, K. kilifi from Kenya, and K. ibadan from Nigeria. A second new genus, Khamiscar, is established for six new species from ...

Description of the final stadium larva of Heliocypha perforata perforata (Percheron), with discussion of the taxonomic characters of the larvae of the genus Heliocypha Fraser (Odonata: Zygoptera: Chlorocyphidae).

The final stadium larva of Heliocypha perforata perforata is described and illustrated for the first time. It is characterized by having a row of filiform setae present laterally on distal half of prementum, 6-7 setae on the outer side of palpal lobe, very long lateral gills and distinct abdominal color pattern. The taxonomic characters of the larvae of the genus Heliocypha Fraser are discussed and summarized. Heliocypha larvae share a high similarity with Rhinocypha in general appearance and cannot be clearly distinguished from the latter in structure.

A new species of Miroculis Edmunds, 1963 (Ephemeroptera: Leptophlebiidae) from Northeastern Brazil

Miroculis stenopterus, sp. nov., is described based on material from State of Pernambuco, Northeastern Brazil. The imago of the new species can be distinguished, among other characteristics, by an uncommon forewing shape, long and narrow, similar to species of genus Microphlebia. The tentatively associated nymph can be distinguished from other species of the genus mainly by the abdominal color pattern and the ratio of labial palp segment 2 to segment 1 (1.01-1.04 x).

Two new species of Thraulodes Ulmer, 1920 (Ephemeroptera: Leptophlebiidae: Atalophlebiinae) from Southeast Brazil.

Two new species of Thraulodes Ulmer, 1920 are described from Rio de Janeiro and São Paulo, Southeastern Brazil, based on male and female imagos. Thraulodes luisae sp. nov. differs from all other species of the genus by the short and wide penes spines, turning up to apex; triangular shape of styliger plate with median projection abrupt and short with rounded apex; abdominal and legs color pattern; and presence of 2-3 weakly marked cross veins basal to bullae. Thraulodes pinga sp. nov. differs from all other species of the genus by the wide shape of styliger plate with median projection short with wide base and truncated apex; abdominal and legs color pattern; and presence of 1 weakly marked cross vein basal to bullae.

Paracloeodes caldensis (Ephemeroptera: Baetidae), an atypical new species from the Colombian Andes.

In the present work, an atypical new species of Paracloeodes Day (Ephemeroptera: Baetidae) is described based on nymphs collected in the Caldas Department, Central Cordillera of Colombia. This represents the first report of the genus from Colombia. The main characteristics that distinguish the new species from congeners are: abundant setae on femora, antennae length twice the width of the head capsule, maxilla with palp twice the length of the galea-lacinia, segment II of the labial palp with a rounded projection and 2.5 times the width of segment III, tarsal claws half the length of their respective tarsi and the abdominal color pattern. The concepts of the genera Paracloeodes, Varipes and Rivudiva are discussed in light of the discovery of P. caldensis n. sp.

Phenotypic Diversity and Landscape Genetics ofEristalis tenaxin a Spatially Heterogeneous Environment, Durmitor Mountain (Montenegro)

The study of the spatial distribution of phenotypic and genetic diversity of pollinators has conservation implications since pollination is a key ecosystem function and a basis for the maintenance of biodiversity. The impact of landscape heterogeneity on the population structure of the important hoverfly pollinator, Eristalis tenax (Diptera, Syrphidae), was investigated. Allele frequencies at allozyme loci, wing traits (size and shape) and abdominal colour pattern were compared using samples from eight locations in the Durmitor National Park, Montenegro. These locations covered a broad range of altitudes and vegetation structures, from deciduous and coniferous forests to alpine meadows. From the conservation point of view, we investigated to what extent the localities in the Durmitor mountain range are connected. Results indicated a lack of population structure in the study area. A genetic clustering analyses based on Bayesian model revealed no resolution among samples, coinciding with FST estimates. Weak...

New species for Thraulodes Ulmer, 1920 (Ephemeroptera: Leptophlebiidae: Atalophlebiinae) and the first key to adults from Brazil.

Four new species of the mayfly genus Thraulodes Ulmer are described based on imagos from Northeastern and Southern Brazil: Thraulodes luizgonzagai sp. nov., Thraulodes sternimaculatus sp. nov., Thraulodes alapictus sp. nov., and Thraulodes pinhoi sp. nov. The new species can be easily differentiated by the abdominal color pattern and genitalia morphology. The first key to adults from Brazil is provided.

<i>Thraulodes bonito</i> sp. nov. (Ephemeroptera: Leptophlebiidae) from Rio de Janeiro State, Southeastern Brazil

A new species of Thraulodes Ulmer, 1920 is described from Rio de Janeiro. The species resembles the recently published Thraulodespelicanus Mariano and Froehlich, 2011 (in Mariano et al. 2011) due to the length and width of the penes. However, Thraulodes bonito sp. nov. differs from this and all other species of the genus by the wide penes, the triangular shape of the styliger plate with median projection short and apex rounded, the abdominal color pattern and the presence of 1-3 weakly marked cross veins basal to bullae. The new species is described based on male imagos, female subimagos and nymphs.

On Munduruku, a new Theraphosid genus from Oriental Amazonia (Araneae, Mygalomorphae)

Munduruku gen. nov. is proposed for the type species Munduruku bicoloratum sp. nov., from Juruti and Santarém, Pará, Brazil. The main diagnostic character of Munduruku gen. nov. is the presence of a subapical, lanceolate keel on the male palpal bulb, which is unique among the basal taxa of Theraphosinae with type III-IV urticating setae. The female spermathecae consist of two spheroid receptacles with funnel-shaped necks, each of which bears a sclerotized area. In both sexes, the abdomen is remarkably patterned, an uncommon feature in adults of New World theraphosids. Both the bulbus lanceolate keel and the abdominal color pattern are hypothesized as synapomorphies of the genus.

Landscape genetics and spatial pattern of phenotypic variation ofEristalis tenaxacross Europe

A study of population connectivity of the migratory insect species, such as dronefly Eristalis tenax (Diptera, Syrphidae), has an essential importance in understanding the relative influence of the evolutionary forces and environmental features that interact in the spatial distribution of molecular and morphological diversity. However, specific study aiming to understand spatial genetic structure of dronefly populations and its migratory potential is lacking. Hence, we studied a spatial pattern of genetic and phenotypic variation of seven European populations of E. tenax incorporating landscape genetic methods using allozyme data, wing size and shape and abdominal colour pattern. Based on the observed lack of genotypic structuring, we suggested that there has been sufficient long-distance gene flow to effectively homogenize population structuring at a broader geographical scale. Wing shape similarity among populations and an overlap of abdominal colour variation showed no clear clustering related to geography, which is in congruence with genetic data. However, genetic (FST values) and phenotypic (wing size) data and landscape genetics indicated subdivision between the Balkan populations (four Serbian samples) and populations from Central (Germany and Switzerland) and Northern (Finland) Europe. These findings indicated a potential connection between the Central and Northern Europe supporting the Central European origin of the flies caught in Finland. Thus, by performing spatial analysis and combining genetic–morphological approach, we shed light on the movement pattern in complex landscapes and thus provided the necessary guidelines to a broad-scale analysis of this widespread generalist pollinator.

A new species of Acentrella Bengtsson (Ephemeroptera: Baetidae) from New York and New England (USA), redescription of the nymph of A. parvula (McDunnough), and key to known adult males of Nearctic Acentrella

A new species Acentrella rallatoma (type locality: Connetquot River, Oakdale, NY, USA) is described from nymphs and reared adults. Additional specimens were studied from southeastern New York, southeastern New Hampshire, coastal Connecticut, and Martha's Vineyard, MA, USA. Nymphs can be separated from those of other Nearctic species by: scraper-like outer incisors of mandibles, cerci alternately banded from bases to tips, and row of robust bristle-like setae (with modified tips) on dorsal edge of femora. Male imagos can be separated from those that lack hind wings by: distinctive colour pattern of abdominal terga, and genitalia with pigmented sclerotised penes cover. Comparative analysis of A. rallatoma with other Nearctic species revealed a lack of comparative data on nymphs of its presumptive sister species A. parvula. To facilitate future studies of this group, the nymph of A. parvula is redescribed and regional differences are discussed. Abdominal colour patterns of A. parvula that vary over its range from Florida, USA to Labrador, Canada are illustrated. Problems concerning genus-level diagnostic characters for Acentrella nymphs and adults are discussed to facilitate placement of future taxa. To complement existing keys to Nearctic nymphs of Acentrella a provisional key to the known adult males is given.

The larva of Progomphus lambertoi Novelo-Gutiérrez, 2007 (Odonata: Gomphidae)

The larva of Progomphus lambertoi is described and illustrated; it belongs to the obscurus-group of Progomphus. It appears closely related to P. belyshevi Belle and P. borealis McLachlan based on stature and size of abdominal dorsal protuberances but is easily separated from these species by abdominal color pattern.