Elytral Colour Pattern Research Articles

Henosepilachna vigintioctomaculata Motschulsky (Coleoptera: Coccinellidae): morphotypes in an East Asian population

The 28-spotted potato ladybird beetle Henosepilachna vigintioctomaculata is an endemic pest of field crops in the Russian Far East. The study on the morphotypic structure of a population of this phytophagous insect can facilitate the monitoring of processes occurring in ecosystems. It might contribute to the research on the endemic fauna of the Russian Far East and reveal how varieties form resistance to pesticides. To study the polymorphism and structure of a potato ladybird beetle population, an analysis of elytral color patterns was conducted. The following features were considered: the size and shape of spots, the intensity of color, the position of spots on the elytra relative to the elytral suture, the presence of merged spots. As the result, nine morphotypes were identified. The morphotype A2 was the most frequent (47.81 %) and followed by the morphotypes A1 and A6. The morphotype A9 had the lowest frequency of occurrence (1.82 %). It was also determined that morphotypes differed in the linear dimension of spots on the elytra. The form A2 was characterized by the largest spots. The size of the color patterns varied from 104.98 ± 0.071 to 297.01 ± 0.065 µ. The form A1 had the smallest spots.

A new species of Ophtalmibidion Martins from French Guiana, and notes on O. luscum Martins (Coleoptera, Cerambycidae, Cerambycinae)

Ophtalmibidion gutta sp. nov. is described from French Guiana. The elytral color pattern of Ophtalmibidion luscum Martins, 1971 is commented on. A key to species of Ophtalmibidion is provided as well as photographs of all species.

Integrative taxonomic review of the genus Peschetius (Coleoptera, Dytiscidae, Hydroporinae) from India with description of two new species

AbstractThe diving beetle genusPeschetiusGuignot, 1942 (Coleoptera: Dytiscidae) in India is reviewed. Integrative taxonomic approach using morphology, multivariate morphometry and genetic analysis of cytochrome oxidase subunit 1 revealed the presence of four species, two of which are described here as new:Peschetius bistroemisp. nov.from southern Western Ghats (Kerala) differs from all known congeners with distinctly broadened male antennomeres IV and V, shape of the prosternal process and the male genitalia;P. nilssonisp. nov.from northern Western Ghats, Rajasthan and Madhya Pradesh is similar to the widespread IndianP. toxophorusGuignot, 1942, from which it differs in habitus, elytral colour pattern and the shape of the male genitalia. New records are presented for the remaining Indian species, namelyP. quadricostatus(Aubé, 1838) andP. toxophorus. All species are diagnosed, illustrated and a key to their identification is provided.

Molecular analysis and morphological variability confirm Hydaticus dhofarensis Pederzani, 2003 as the westernmost population of the Indomalayan H. bipunctatus Wehncke, 1876 (Coleoptera: Dytiscidae)

Hydaticus dhofarensis Pederzani, 2003, the only endemic diving beetle known from Dhofar Region is newly recorded from Masirah Island, central Oman. Analysis of 3ʹ region of the mitochondrial cytochrome oxidase I gene (cox1) reveals that specimens from Oman differs only in 1% of the sequence from specimens of the widespread Indomalayan H. bipunctatus Wehncke, 1876. In addition, study of extensive material of H. dhofarensis shows that the elytral colour pattern and body shape, previously considered as diagnostic characters, vary significantly, and especially the specimens from more northern localities agree completely with H. bipunctatus. Therefore, Hydaticus dhofarensis is considered as a junior subjective synonym of H. bipunctatus. The occurrence of this predominantly Indomalayan species in southern Oman is briefly discussed.

New color patterns and new synonym of Odontolabis sinensis (Westwood, 1848) (Coleoptera: Lucanidae): insights from a multilocus phylogeny and species delimitation.

Taxonomy of Odontolabis sinensis (Westwood, 1848) and Odontolabis fallaciosa Boileau, 1901 has long been a controversial issue due to their highly morphological similarity except for elytral color patterns. In the present work, we assessed their taxonomic status by combining molecular phylogeny and species delimitation based on multilocus datasets (COI, 16S rDNA, Cytb, CAD, Wingless). Phylogenetic analyses under both Maximum Likelihood inference and Bayesian inference recovered identical topologies. All the examined individuals in the clade of O. sinensis and O. fallaciosa formed into five subclades belonging to four color patterns, respectively. The Kimura-2-Parameter (K2P) genetic distance analysis yielded a low mean value (0.0108-0.0295). The multiple species delimitations (ABGD, PTP and GMYC) reinforced them to be one MOTU. Our results suggest that these clades belong to the same species, and thus we propose O. fallaciosa to be a junior subjective synonym of O. sinensis. We also found two new color patterns corresponding to two clades from Southwestern China (north of 20°N and east of 105°E), respectively displaying the reddish-orange, slenderly rimmed patch and brownish-orange broad patches along the elytral edge, which was probably attributable to both historical and ecological factors in this particular region.

Evolutionary fine-tuning of background-matching camouflage among geographical populations in the sandy beach tiger beetle.

Background-matching camouflage is a widespread adaptation in animals; however, few studies have thoroughly examined its evolutionary process and consequences. The tiger beetle Chaetodera laetescripta exhibits pronounced variation in elytral colour pattern among sandy habitats of different colour in the Japanese Archipelago. In this study, we performed digital image analysis with avian vision modelling to demonstrate that elytral luminance, which is attributed to proportions of elytral colour components, is fine-tuned to match local backgrounds. Field predation experiments with model beetles showed that better luminance matching resulted in a lower attack rate and corresponding lower mortality. Using restriction site-associated DNA (RAD) sequence data, we analysed the dispersal and evolution of colour pattern across geographical locations. We found that sand colour matching occurred irrespective of genetic and geographical distances between populations, suggesting that locally adapted colour patterns evolved after the colonization of these habitats. Given that beetle elytral colour patterns presumably have a quantitative genetic basis, our findings demonstrate that fine-tuning of background-matching camouflage to local habitat conditions can be attained through selection by visual predators, as predicted by the earliest proponent of natural selection.

Development and evolution of color patterns in ladybird beetles: A case study in Harmonia axyridis.

Many organisms show various geometric color patterns on their bodies, and the developmental, evolutionary, genetic, and ecological bases of these patterns have been intensely studied in various organisms. Ladybird beetles display highly diverse patterns of wing (elytral) color and are one of the most attractive model organisms for studying these characteristics. In this study, we reviewed the genetic history of elytral color patterns in the Asian multicolored ladybird beetle Harmonia axyridis from the classical genetic studies led by the pupils of Thomas Hunt Morgan and Theodosius Dobzhansky to recent genomic studies that revealed that a single GATA transcription factor gene, pannier, regulates the highly diverse elytral color patterns in this species. We also reviewed and discussed the developmental and evolutionary mechanisms driven by the pannier locus in H.axyridis. In the development sections, we focused on the following two topics: (a) how the red (carotenoid) and black (melanin) pigmentation of elytra is regulated by the pannier and pigmentation genes and (b) how the diverse color patterns are formed by integrating regulatory inputs from other genes involved in wing development. In the evolution section, we subsequently focused on the highly diversified DNA sequences within the first intron of pannier that are 56-76kb long and that were generated through recurrent multiple inversions. Furthermore, we discussed how these recurrent inversions have driven the diversification of color patterns throughout evolution.

Repeated inversions within a pannier intron drive diversification of intraspecific colour patterns of ladybird beetles

How genetic information is modified to generate phenotypic variation within a species is one of the central questions in evolutionary biology. Here we focus on the striking intraspecific diversity of >200 aposematic elytral (forewing) colour patterns of the multicoloured Asian ladybird beetle, Harmonia axyridis, which is regulated by a tightly linked genetic locus h. Our loss-of-function analyses, genetic association studies, de novo genome assemblies, and gene expression data reveal that the GATA transcription factor gene pannier is the major regulatory gene located at the h locus, and suggest that repeated inversions and cis-regulatory modifications at pannier led to the expansion of colour pattern variation in H. axyridis. Moreover, we show that the colour-patterning function of pannier is conserved in the seven-spotted ladybird beetle, Coccinella septempunctata, suggesting that H. axyridis’ extraordinary intraspecific variation may have arisen from ancient modifications in conserved elytral colour-patterning mechanisms in ladybird beetles.

Influence of Elytral Color Pattern, Size, and Sex of Harmonia axyridis (Coleoptera, Coccinellidae) on Parasite Prevalence and Intensity of Hesperomyces virescens (Ascomycota, Laboulbeniales).

Harmonia axyridis is an invasive ladybird (Coleoptera, Coccinellidae) with the potential to outcompete native ladybird species in its invasive distribution area. It was introduced as a biological control agent in many countries but has also spread unintentionally in many others. Hesperomyces virescens (Ascomycota, Laboulbeniales) is a minute (200–400 µm in size) biotrophic fungus that infects over 30 species of ladybirds. The aim of this study was to evaluate whether the elytral color pattern, size, and sex of Ha. axyridis affect infection by H. virescens. Coloration in Ha. axyridis has been linked to the presence of an antimicrobial alkaloid (harmonine). In fall 2016, we collected 763 Ha. axyridis individuals in Cambridge, Massaschusetts, of which 119 (16%) bore H. virescens fruiting bodies. We analyzed 160 individuals (80 infected, 80 uninfected) concerning the intensity of infection by H. virescens. Elytral sizes and coloration patterns were quantified using digital photography and analytical methods. Smaller ladybirds had a higher prevalence and higher intensity of parasitism. Additionally, male ladybirds bore more thalli compared to female ladybirds. Elytral color patterns had an effect on neither prevalence nor intensity of infection by Laboulbeniales in our dataset, although we found a slight trend to higher intensity of parasitism in more melanic males. This suggests that the development of Laboulbeniales might be affected by certain insect alkaloids.

Description of the male of Antodice quadrimaculata Martins Galileo, 2003 (Coleoptera, Cerambycidae, Lamiinae), with new country record for the species.

The genus Antodice Thomson, 1864 was revised by Martins Galileo (1998) and currently includes 27 species (Tavakilian Chevillotte 2017), distributed from Mexico to southern South America. Based on a single female specimen collected in Arroyo Cristal, Ka'azapá, Paraguay, the species Antodice quadrimaculata was first described by Martins Galileo in 2003. The holotype specimen was collected on 20 November 1999 by J. Jensen and is deposited in the Museum of Zoology of the University of São Paulo, Brazil. With the help of Carlos Aguilar, from Paraguay's National Museum of Natural History, we were able to determine the exact location where the holotype was collected. With the collection and the description of the male, presented herein, we describe the male of this species record its occurrence in Brazil, a new country record.We identified this species as belonging to the group of Antodice species with yellowish flagellomeres and a black apex, resembling Antodice venustula Lane, 1973 in its elytral color pattern. In A. venustula, the elytra are covered with whitish pubescence and exhibit only two patches of compact white pubescence. In A. quadrimaculata, according to Martins Galileo (2003), the elytra are of a reddish color with whitish pubescence on the dorsal anterior area and close to the apexes, and they also have three patches of compact white pubescence. The specimens of A. quadrimaculata cited herein were collected in the Iguaçu National Park (Parque Nacional do Iguaçu-PNI), the largest fragment of Atlantic forest in southern Brazil, located in the western region of the state of Paraná. The insects were collected using light traps, set up on nights with a new moon. The artificial light source was a 500-Watt incandescent lamp powered by a Honda EP 2500 generator. Sampling began at 6 p.m., ending between midnight and 3 a.m. the next day. The studied material was deposited in the entomological collection of the Museum of Zoology at the State University of Londrina (Universidade Estadual de Londrina), Londrina, Brazil (MZUEL). To better represent the expansion of the geographical distribution of the species from the holotype recorded in Paraguay (Fig. 5, 6), the cartographic material (Fig. 1) was produced using ArcGIS Software 9.0®. The map database was obtained from the Institute of Land, Cartography and Geosciences, (Instituto de Terras, Cartografia e Geologia do Paraná), Curitiba, Brazil (ITCG).

Two new species of Conognatha Eschscholtz, 1829 (Coleoptera, Buprestidae, Stigmoderini) from Southeast and South Brazilian regions with distributional notes

Conognatha (Pithiscus) coffeatus sp. nov. and Conognatha (Pithiscus) puris sp. nov., both from the Atlantic Rainforest (type locality: Itatiaia, Rio de Janeiro State, Brazil), are described and illustrated. They differ from each other mainly by the elytral colour pattern, presence of a short longitudinal groove between the vertex and the frons in C. (P.) puris sp. nov., and differences in frons shape, antennae sensory fields, pronotum and aedeagus. The distribution of C. (P.) gounellei is extended to the State of Minas Gerais, Brazil. A modified key to include the new species, as well as illustrations, are presented.

A new species of Agrilozodes Théry, 1927, new record for A. pygmaeus (Kerremans, 1897) and a key for the genus (Coleoptera, Buprestidae).

Agrilozodes bellamyi sp. nov. from the Caatinga Biome (type locality: Juazeirinho, Paraíba, Brazil) is described and illustrated. It differs from the other five known species mainly by the moderate longitudinal elevation between the eyes, posterolateral angles of pronotum acute and oblique, mesoepisternum excavated, elytral color pattern and elevation of interestriae 2 and 4. The distribution of A. pygmaeus is extended to Rio de Janeiro, Brazil. Photographs of six species as well as a key to the six species of the genus are provided.

Ancyronyx jaechi sp.n. from Sri Lanka, the first record of the genus Ancyronyx Erichson, 1847 (Insecta: Coleoptera: Elmidae) from the Indian Subcontinent, and a world checklist of species

Ancyronyx jaechi sp. n. from Kegalle District, Sabaragamuwa Province, Sri Lanka is described. The new species is rec-ognized by a unique combination of the elytral colour pattern, as well as the shape and size of the male sternite IX, theaedeagus, the female ovipositor, and the secondary sexual characters. An updated world checklist of the species of Ancy-ronyx Erichson, 1847 including authority clarification for A. montanus Freitag & Balke, 2011 is provided. The distributional area of the genus and its diagnostic characters are discussed. The habitats of Ancyronyx species are briefly discussed.

Using biological traits to explain ladybird distribution patterns

AbstractAim Determining to what extent differing distribution patterns are governed by species’ life‐history and resource‐use traits may lead to an improved understanding of the impacts of environmental change on biodiversity. We investigated the extent to which traits can explain distribution patterns in the ladybird fauna (Coleoptera: Coccinellidae) of Great Britain.Location The British mainland and inshore islands (Anglesey, the Isle of Wight and the Inner Hebrides).Methods The distributions of 26 ladybird species resident in Britain were characterized in terms of their range size (from 2661 10‐km grid squares across Britain) and proportional range fill (at 10‐ and 50‐km scales). These were assessed relative to five traits (body length, elytral colour pattern polymorphism, voltinism, habitat specificity and diet breadth). The role of phylogenetic autocorrelation was examined by comparing the results of phylogenetic and generalized least‐squares regressions.Results Diet breadth was the only trait correlated with range size: species with broad diets had larger range sizes than dietary specialists. Range fill was sensitive to recording intensity (a per‐species measure of the mean number of records across occupied squares); models including both recording intensity and range size provided more explanatory power than models incorporating ecological traits alone.Main conclusions Habitat specificity is often invoked to explain the distribution patterns of species, but here we found diet breadth to be the only ecological correlate of both range fill and range size. This highlights the importance of understanding predator–prey interactions when attempting to explain the distribution patterns of predatory species. Our results suggest that the diet breadth of predatory species is a better correlate of range size and fill than other measures, such as habitat specificity.

Two Cryptic Species in Brontispa longissima (Coleoptera: Chrysomelidae): Evidence from Mitochondrial DNA Analysis and Crosses between the Two Nominal Species

Abstract The beetle Brontispa longissima (Gestro) (Coleoptera: Chrysomelidae) is a serious invasive pest of the coconut palm, Cocos nucifera I., in Southeast Asia and the Pacific region. Genetic analysis is essential to ecological and evolutionary study of such invasive species. We therefore conducted molecular analyses by using partial sequences (1044 bp) of the mitochondrial cytochrome oxidase subunit I (COI) genes of B. longissima collected from several locations. We found two monophyletic groups: one distributed over a limited area (Australia, Papua New Guinea, Samoa, and Sumba Island; referred to as the Pacific group) and the other collected from a wide area of Asia and the Pacific region (referred to as the Asian group). We compared the biological and morphological traits of the two groups. We found that insects in the Pacific group had a shorter developmental time from hatching to adult emergence, produced fewer eggs, and had a larger adult body size than insects in the Asian group. Elytral color patterns did not differ between the two groups. Our interpopulation crosses produced significantly fewer progeny than intrapopulation crosses, suggesting that B. longissima represents two cryptic species.

Pterorhopalus mizotai (Coleoptera, Carabidae, Paussinae, Paussini), a New Genus and Species of Platyrhopalina from Sabah, Borneo

Pterorhopalus mizotai gen. et sp. nov. (Paussini, Platyrhopalina) is described based on a single specimen collected with a Malaise trap in the Crocker Range, Negeri Sabah, Borneo, Malaysia. A key to the genera of the subtribe Platyrhopalina is presented. The new genus is related to Platyrhopalus, but is readily distinguished from it by the structure of the antennae. Convergence of the elytral colour pattern among the Oriental paussines is discussed.

FIVE NEW PUERTO RICAN LONGHORN BEETLES AND OTHER NOTES ON WEST INDIAN ACANTHOCININI (COLEOPTERA: CERAMBYCIDAE: LAMIINAE)

Five new species of Cerambycidae from Puerto Rico, Antilleptostylus guilartensis, Leptostylopsis guanica, Leptostylopsis yukiyu, Leptostylopsis monin, and Urgleptes borikensis are described. A new combination, Antilleptostylus brunneofasciatus (Fisher), and new synonymy, Leptostylopsis oakleyi (Fisher) = Leptostylopsis gundlachi (Fisher) are also proposed. Habitus figures of the new species, keys for separating the Puerto Rican species of Leptostylopsis Dillon and Urgleptes Dillon, a key and figures for separating the species of Antilleptostylus Gilmour, a figure to help in separating Leptostylopsis gundlachi Fisher and two new related species, and a figure of some typical elytral color pattern variations in Urgleptes borikensis are presented.

Morphological Variation within and between Four Closely Related Phyllotreta Species: P. dilatata, P. flexuosa, P. ochripes and P. tetrastigma (Coleoptera: Chrysomelidae)

Phyllotreta dilatata Thomson, 1866, P. flexuosa (Illiger, 1794) P. ochripes (Curtis, 1837) and P.tetrastigma (Comolli, 1837) are four closely related, morphologically similar flea beetle species which are usually distinguished according to elytral colour pattern and also show morphological differences in the genitalia. Here both uni- and multivariate analyses are used to study intra- and interspecific morphological variation for the four species. All species seem to differ in overall morphology and the results also support the idea of regarding P. tetrastigma and P. flexuosa as two different systematic entities.

Notes on Identification and Ecology of Tumbling Flower Beetles (Mordellidae) from Ossabaw Island, Georgia

A unique opportunity on April 25, 1995, to intensively search for mordellid beetles resulted in finding four species on Ossabaw Island, Chatham County, Georgia. This is the first report of their host plant associations and the sympatry of Mordellistena trifasciata and M. minuta. Historically, there has been confusion between these two species (Liljeblad 1945, Khalaf 1971) because their elytral color patterns are practically identical. I provide some overlooked distinctions between them. Mordellistena pubescens (Fabricius) (Fig. 1): 6 specimens on black cherry Prunus serotina (Rosaceae), sparkleberry Vaccinium arboreum (Ericaceae), and wax myrtle Myrica cerifera (Myricaceae). According to Liljeblad (1945), the color patterns of this species are quite variable. The dermal color of the Ossabaw specimens varies from reddish brown to black. There are three (sometimes four) dark spots surrounded by cinereous pubescence on the basal half (posterior) of the pronotum. Cinereous pubescence totally covers the anterior portion of the pronotum. The elytral markings of golden pubescence in the Ossabaw specimens are inconsistent with those illustrated by Liljeblad (1945). Because both base and apex are covered with golden pubescence, there appear four golden crossbands on the elytron. The lateral margins are heavily covered with golden pubescence that encloses three dark spots on the elytron. The middle dark spot is usually more or less a crossband. In one specimen, the apical dark spot is so heavily encroached by the apical and penultimate golden crossbands that it is almost obliterated. The short oblique ridges on the posterior tibia vary from 2-6 with the apical two obvious and the basal remainder rudimentary; the basitarsus has 2-4 ridges, again only the apical two are obvious; the second tarsal segment has only one ridge with a rudimentary second barely visible. These counts by Liljeblad (1945) are 3-4, 3, and 2, respectively. Determination of the number of ridges on the posterior leg is therefore highly subjective. Mordellistena andreae andreae Leconte (Fig. 2): 10 specimens on black cherry Prunus serotina (Rosaceae), sparkleberry Vaccinium arboreum (Ericaceae), wax myrtle Myrica cerifera (Myricaceae). Liljeblad (1945) named three varieties of this species. The form M. ancilla, regarded as a variety of M. andreae (Liljeblad 1945, Bright 1986), was said by Khalaf (1971) to have the penultimate segments of the anterior and middle tarsi truncated at apex. These segments on all Ossabaw specimens are slightly emarginate or notched at apex. This may be why Khalaf called ancilla a full species. Head and thorax are yellow in the male and black in the of M. andreae andreae. However, one from Ossabaw has a totally ferruginous head. Liljeblad (1945) also reported female with black head except a space in front of antennae which is yellowish. Apparently head color is variable in this form. Mordellistena trifasciata (Say) (Fig. 3 & Table 1): 2 specimens on red buckeye Aesculus pavia (Hippocastanaceae) and sparkleberry Vaccinium arboreum (Ericaceae).

Temperature-Dependent Development in a Polymorphic Lady Beetle, Calvia quatuordecimguttata (Coleoptera: Coccinellidae)

The influence of temperature on the development rate and expression of 3 elytral color patterns in the lady beetle, Calvia quatuordecimguttata (L.), was assessed at 6 constant temperatures between 10 and 34°C. The expression of the 3 elytral color patterns was discrete and independent of temperature treatment. No differences were observed among the color morphs in the real or physiological time for egg-to-adult development, or for pupal weight. However, temperature did influence survival and growth rates of the overall population. No eggs hatched at 34°C. Larval mortality was high at 10°C and moderate between 14 and 30°C. Development time from oviposition to adult was 14.6 ± 0.9 d at 30°c and 95.6 ± 9.0 d at 10°C. The total heat-unit requirement for egg to adult development was 274.1 DD above a mean development-threshold of 8.2°C. Pupal weight differed among temperature treatments and was greatest at 10-22°C, and lowest at 26 and 30°C.