Variation In Male Genitalia Research Articles

Incurvaria pirinella sp. nov., a new species of the vetulella species-group (Lepidoptera, Incurvariidae) from Bulgaria, with release of DNA barcodes for European species of Incurvaria

IncurvariapirinellaJunnilainen, Kaitila & Mutanen,sp. nov.is described from Bulgaria based on specimens collected by netting and artificial light from several low-elevation localities in Bulgaria. The species is morphologically and genetically most similar toI.triglavensisHauder, 1912. Differences between these two species are present in external appearance and genitalia of both sexes. Additionally,I.pirinellashows a distance of 4.74% to its nearest neighbourI.triglavensisin the standard DNA barcoding marker (COI-5P). We provide preliminary observations of phylogenetic affinities of EuropeanIncurvariaand briefly discuss habitat preferences of some species. All species have distinct barcodes with minimum K2P divergences between species averaging 7.05% (range 1.2–12.8%). A world checklist ofIncurvariaHaworth, 1828 is provided and DNA barcodes for all European species are here released. Finally, we document morphological variation in male genitalia withinI.triglavensisHauder, 1912.

Cryptic diversity in Andrognathuscorticarius Cope, 1869 and description of a new Andrognathus species from New Mexico (Diplopoda, Platydesmida, Andrognathidae).

Andrognathus is a genus of small, thin-bodied millipedes found in deciduous forests of North America. Poorly understood, these organisms inhabit decaying wood and have morphologically conserved and difficult-to-identify sexual characters that have limited study historically. Recent use of scanning electron microscopy has uncovered variation in male genitalia that was previously unknown in the genus. The distribution of Andrognathus and the extent of this variability across the continent, however, were undocumented, and a wealth of natural history collections remained uncatalogued. Here a new species of Andrognathus is described from New Mexico, Andrognathusgrubbsisp. n., natural history collections are utilized to create a comprehensive map of the genus, and a neotype established for the type species, Andrognathuscorticarius Cope, 1869. Analysis of the cytochrome oxidase I gene (COI) for A.corticarius was completed for the type series and individuals across the species distribution, but little variation was found. Andrognathusgrubbsisp. n. joins A.corticarius and A.hoffmani Shear & Marek, 2009 as the only members of the genus.

Two new species of tribe Agalliini (Hemiptera: Cicadellidae: Megophthalminae) with note on intraspecific variations.

Two new species of leafhoppers, Durgades sineprocessus sp. nov. (From Himachal Pradesh: Kalpa) and Japanagallia dolabra sp. nov. (From Sikkim: Lachung) from India, are described and illustrated. Photographic illustrations of Durgades aviana Viraktamath and a detailed note on intraspecific variation in male genitalia of Austroagallia sinuata (Mulsant Rey) are also provided. Material is deposited in the National Pusa Collection, Division of Entomology, Indian Council of Agricultural Research-Indian Agricultural Research Institute (ICAR-IARI), New Delhi, India.

Cladistic classification of Mecyclothorax Sharp (Coleoptera, Carabidae, Moriomorphini) and taxonomic revision of the New Caledonian subgenus Phacothorax Jeannel

The 15 species of Mecyclothorax Sharp precinctive to New Caledonia are revised and shown by cladistic analysis to comprise a monophyletic lineage, here treated as subgenus Phacothorax Jeannel. The New Caledonian species of subgenus Phacothorax include Mecyclothoraxfleutiauxi (Jeannel), M.najtae Deuve, and 13 newly described species: M.jeanneli sp. n., M.laterobustus sp. n., M.laterorectus sp. n., M.laterosinuatus sp. n., M.laterovatulus sp. n., M.manautei sp. n., M.megalovatulus sp. n., M.octavius sp. n., M.paniensis sp. n., M.picdupinsensis sp. n., M.plurisetosus sp. n., and two jointly authored species; M.kanak Moore & Liebherr sp. n., and M.mouensis Moore & Liebherr sp. n.. subgenus Phacothorax is one of five subgenera recognized within genus Mecyclothorax based on cladistic analysis of 65 exemplar taxa utilizing information from 137 morphological characters. The four other monophyletic subgenera include the precinctive Australian Eucyclothorax subgen. n. (type species Mecyclothoraxblackburni [Sloane]), the precinctive Queensland Qecyclothorax subgen. n. (type species Mecyclothoraxstoreyi Moore), the precinctive New Zealand Meonochilus Liebherr & Marris status n., and the geographically widespread and very diverse nominate subgenus, distributed from St. Paul and Amsterdam Islands, eastward across Australia and New Guinea, and in the Sundas, Timor Leste, Lord Howe and Norfolk Islands, New Zealand, and the Society and Hawaiian Islands. The biogeographic history of Mecyclothorax can be derived from the parsimony cladogram time-calibrated by times of origin of particular geographic areas inhabited by resident representative species. Based on sister-group status of subgenus Phacothorax and subgenus Mecyclothorax, and occupation of Lord Howe Island–an island originating no earlier than 6 Ma–by the earliest divergent lineage within subgenus Mecyclothorax, the ancestor of present-day Phacothorax spp. is hypothesized to have colonized New Caledonia 6 Ma, subsequent both to Cretaceous Gondwanan vicariance as well as any Oligocene submergence. Area relationships among the New Caledonian Phacothorax point to earliest diversification incorporating the northern massifs, and most recent diversification on the ultramafic volcanic substrates in the south of Grand Terre. Flight wing loss has played an important role in shaping the various island faunas, both in their morphology as well as their diversity. The retention of flight capability in only a few of the many hundred Mecyclothorax spp. is presented in light of how populations evolve from macropterous colonizing propagules to vestigially winged specialists. Interspecific differences in genitalic structures for the sister-species pair M.fleutiauxi + M.jeanneli are shown to involve functional complementarity of male and female structures. Extensive geographic variation of male genitalia is demonstrated for several New Caledonian Mecyclothorax spp. This variation deviates from the geographically uniform male genitalia exhibited by species in the hyperdiverse Mecyclothorax radiation of Haleakalā volcano, Maui, suggesting that extensive sympatry occurring among species in that diverse species swarm selects for stability within this mate recognition system. Conversely, lower levels of sympatry characterizing the depauperate New Caledonian radiation permit the presence of more extensive male genitalic variation, this variation not selected against due to the lower likelihood of interspecific mating mistakes.

Integration and modularity in the male genitalia and parameres of Belostoma species of bifoveolatum group sensu Lauck, 1962 (Insecta, Heteroptera, Belostomatidae)

The bifoveolatum group comprises three known species (Belostoma angustum Lauck, B. bifoveolatum (Spinola), and B. elegans (Mayr)), with representatives occurring in southern and south-eastern South America, as well as along the Andes. These species, however, are cryptic with regard to body dimensions and male genitalia. Much of this cryptic variation in male genitalia is still misunderstood, so that proposed keys to bifoveolatum species are scarce and have been based only on body dimensions. In fact, it is not understood whether different parts of male genitalia covary themselves in the integrated way, or if parameres are somehow associated with male genitalia. This paper investigates whether there is expressive variation and integration in the shape of intromitent parts of male genitalia and parameres through specimens of those species from different southern South American localities, by using geometric morphometrics. We also test the hypotheses that the base of phallotheca [PHA]/dorsal arms [DA] subdivision, as well as base/apex of parameres, constitute separate modules. We semi- and landmarked PHA and DA, as well as the right paramere [PA], of 89 B. angustum males, four males of B. bifoveolatum and eight of B. elegans. To eliminate all non-shape variation, point configurations were subjected to the generalised least-squares Procrustes superimposition. A multilevel approach showed that the patterns of integration within individual, among individual and among populations centred by species are similar, with total variation concentrated in a few of the available dimensions. Accordingly, this correspondence is apparent with the very high values of matrix correlations between the covariance matrices for within-species-locality and among localities (r=0.91 for PHA+DA and r=0.86 for VD). Fluctuating asymmetry was not negligible for PHA+DA and it seems that there might be little agreement between it and the other levels of variation (matrix correlation using individual variation, r=0.34. P<0.0001; matrix correlation using variation among population, r=0.29, P<0.0001). After eliminating size effects, morphological integration between PHA+DA and PA was significant (RV=0.058, P=0.0313), which might have enabled greater elaboration of these parts resulting in their greater and faster diversification at the individual level. Our results indicated poor agreement between different levels of variation with regard to fluctuating asymmetry, such that direct developmental interaction is not important for all levels of covariation between PHA+DA and PA through bifoveolatum group of species. Our findings suggest the lack of diagnostic importance of the PHA+DA and VD to differentiate the species B. angustum and B. elegans, despite of their integration. Both DA/PHA and apex/base of PA modularity hypotheses were not refuted across all levels, which might be an indicative of the lack of integration between PA and PHA+DA at higher levels of organisation, such as among populations.

The function and evolution of male and female genitalia in Phyllophaga Harris scarab beetles (Coleoptera: Scarabaeidae).

Genitalia diversity in insects continues to fuel investigation of the function and evolution of these dynamic structures. Whereas most studies have focused on variation in male genitalia, an increasing number of studies on female genitalia have uncovered comparable diversity among females, but often at a much finer morphological scale. In this study, we analysed the function and evolution of male and female genitalia in Phyllophaga scarab beetles, a group in which both sexes exhibit genitalic diversity. To document the interaction between male and female structures during mating, we dissected flash-frozen mating pairs from three Phyllophaga species and investigated fine-scale morphology using SEM. We then reconstructed ancestral character states using a species tree inferred from mitochondrial and nuclear loci to elucidate and compare the evolutionary history of male and female genitalia. Our dissections revealed an interlocking mechanism of the female pubic process and male parameres that appears to improve the mechanical fit of the copulatory position. The comparative analyses, however, did not support coevolution of male and female structures and showed more erratic evolution of the female genitalia relative to males. By studying a group that exhibits obvious female genitalic diversity, we were able to demonstrate the relevance of female reproductive morphology in studies of male genital diversity.

The Meloidae (Coleoptera) of Australasia: a generic review, descriptions of new taxa, and a challenge to the current definition of subfamilies posed by exceptional variation in male genitalia

The seven Australasian genera of blister beetles (Coleoptera : Meloidae : Nemognathinae) are reviewed. Included are a key to genera, generic synopses and descriptions of two new genera of Nemognathini, Australozonitis and Pulchrazonitis, as well as a new monotypic tribe Palaestrini, which features a bauplan of male genitalia unique not only to the subfamily Nemognathinae but to the entire family. The genus Palaestra is redefined to include several Australasian, Asian and African species previously assigned to Zonitis. Exceptional variation of male genitalia encountered in the Palaestrini challenges current subfamily definitions, which are partly based on male genitalic structure and correlated sexual behaviour. Generic synopses include synonyms, type species, number of species, geographic distribution, significant references on taxonomy, life history and morphology, and additional notes. Forty-six new combinations are proposed for species previously in Zonitis. Distribution and relationship of tribes within the Nemognathinae, as well as the biogeography of the Australasian Meloidae are outlined and discussed.

Male genital length and mating status differentially affect mating behaviour in an earwig

Phenotypic variation in male genitalia may affect copulation behaviour, which can have important fitness consequences for males. Male genitalia commonly possess traits that increase male control over copulation, but in species where females control mating, a poor functional understanding often prevents insight into the processes responsible for such effects. Here, I investigate the effect of male genital length on copulation behaviour in the earwig Euborellia brunneri, where both sexes exhibit extremely elongated genitalia that correspond in shape. This model system is particularly suitable because pairs mate repeatedly and females can limit both the number and duration of copulations. I used both virgin and mated males and females in a double-mating design because longer male genitalia confer benefits in sperm competition. Consistent with a greater predicted male mating effort in mated females, the duration of individual copulations increased, but this traded off against mating frequency as cumulative mating duration remained unchanged. In contrast, male genital length increased both individual and cumulative mating duration, regardless of mating status. This difference suggests that, while males may modify copulation duration in response to mating status, females facultatively adjust mating frequency to prevent mating excessively or express preferences for increased male genital length. Notably, this study demonstrates that male genital phenotypes that are successful in sperm competition also enjoy female-mediated mating benefits.

Phenotypic and genetic variation in male genitalia in the seedbug, Lygaeus equestris (Heteroptera)

Male genitalia evolve through sexual selection and, in insects, tend to show negative static allometry, low phenotypic variation, and are usually relatively small. Much less is known about the genetic variation and heritability of male genitalia. Additionally, in instances where the intromittent organ is greatly elongated, it is unclear whether typical patterns of genital scaling and variation also apply. In the present study, we investigated the allometry, variation, and heritability of male genital length in the seedbug, Lygaeus equestris, a species with a greatly elongated intromittent organ (i.e. almost as long as male body size). We found that genital length was negatively allometric, in spite of its great length, and was no more variable than nongenital traits. Additionally, genital length was significantly heritable and had considerable evolvability. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 98, 400–405.

Natural selection and genital variation: a role for the environment, parasites and sperm ageing?

Male genitalia are more variable between species (and populations) than other organs, and are more morphologically complex in polygamous compared to monogamous species. Therefore, sexual selection has been put forward as the major explanation of genital variation and complexity, in particular cryptic female choice for male copulatory courtship. As cryptic female choice is based on differences between males it is somewhat paradoxical that there is such low within-species variation in male genitalia that they are a prime morphological identification character for animal species. Processes other than sexual selection may also lead to genitalia variation but they have recently become neglected. Here I focus on pleiotropy and natural selection and provide examples how they link genitalia morphology with genital environments. Pleiotropy appears to be important because most studies that specifically tested for pleiotropic effects on genital morphology found them. Natural selection likely favours certain genital morphology over others in various environments, as well as by reducing re-infection with sexually transmitted diseases or reducing the likelihood of fertilisation with aged sperm. Both pleiotropy and natural selection differ locally and between species so may contribute to local variation in genitalia and sometimes variation between monogamous and polygamous species. Furthermore, the multitude of genital environments will lead to a multitude of genital functions via natural selection and pleiotropy, and may also contribute to explaining the complexity of genitalia.

Tumbling Flower Beetles from New Zealand (Coleoptera: Mordellidae) with New Synonymies for Some Australian Species

There are six species of tumbling fl ower beetles (Coleoptera: Mordellidae) from New Zealand in five genera: Hoshihananomia antarctica (White 1846), Mordella promiscua Erichson 1842, Mordella jucunda (Broun 1880), Stenomordellaria neglecta (Broun 1880), Zeamordella monacha Broun 1886, and Tolidopalpus nitidicoma (Lea 1929). Machairophora Franciscolo 1943 is a valid revised synonym under Hoshihananomia Kono 1935; Hoshihananomia tibialis (Broun 1880) and Machairophora tibialis (Broun 1880) are junior synonyms of H. antarctica; H. multiguttata (Waterhouse 1878) and H. dumbrelli (Lea 1895) are transferred from Mordella as new combinations. Mordellistena Broun 1880 is an occupied name of Mordellistena Costa 1854. The former two species in that genus are now Mordella jucunda and Stenomordellaria neglecta. I redescribe M. jucunda and provide justifi cation for its previous transfer from Mordellistena to Mordella, making Mordellistena Broun a new junior synonym of Mordella L. Mordella detracta Pascoe 1876, M. bella Waterhouse 1878, M. elegantula Waterhouse 1878, M. felix Waterhouse 1878, and M. limbata Waterhouse 1878 are five new junior synonyms of M. promiscua, of which great withinspecies variation in male genitalia is documented for the first time. Trichotomoxia demarzi Ermisch 1962 and Mordella graphiptera Champion 1895 are two new junior synonyms of Z. monacha. The generic definition of Zeamordella requires revision to accommodate the variation in the shape of scutellum from semicircular to trapezoidal. As a result, Trichotomoxia Franciscolo 1950 only differs from Zeamordella Broun 1886 in the shape of last maxillary palpomere: securiform in the former, transverse isosceles in the latter. Z. madagascariensis (Ermisch 1962) is transferred from Trichotomoxia as a new combination accordingly. I redesignate the specimen labeled by Broun from Pokeno in the Natural History Museum, London (BMNH), as the neolectotype of Z. monacha, contra Franciscolo (1980). Tolidopalpus nitidicoma is identified as the sixth, most recently recorded, species from New Zealand; it is transferred from Mordella as a new combination and redescribed in detail. Phenology and larval host plants are summarized. The New Zealand mordellid fauna has close relationships with that of Australia.

Size and Shape Differences in Genitalia of Males from Sympatric and Reproductively Isolated Populations of &lt;I&gt;Anthocoris antevolens&lt;/I&gt; White (Heteroptera: Anthocoridae) in the Yakima Valley, Washington

Anthocoris antevolens White (Heteroptera: Anthocoridae) is a widespread predatory bug in North America commonly associated with deciduous trees and shrubs. Unpublished observations showed that there is considerable geographic variation in male genitalia in this species and that the variation may lead to reproductive isolation among geographically separated populations. We show that male bugs from two sympatric populations in the Yakima Valley, Washington, one occurring on oak (Quercus garryana Douglas) and the other collected from willow (Salix sp.), differed in size and shape of the phallus and clasper. Mating trials showed that males from the oak source successfully inseminated females from the oak source in 75% of pairings; insemination success for males from the willow source paired with females from the willow source was somewhat lower at 62%. In nonlike crosses (oak × willow, willow × oak), males failed to inseminate the female in 100% of pairings, despite vigorous mating attempts by the males. Copulation duration was independent of population source. However, males from the willow source initiated copulation attempts significantly sooner in the assay than males from the oak source, irrespective of female source. We interrupted copulating pairs by freezing them with liquid nitrogen and showed that males in nonlike crosses generally had failed to fully inflate the phallus in the female. Results support statements made elsewhere that A. antevolens is actually composed of an unknown number of reproductively isolated cryptic species.

Geographical variation in male genitalia inBrachyrhaphis episcopi(Poeciliidae): is it sexually or naturally selected?

Male poeciliid fishes inseminate females using an intromittent organ called the gonopodium. Here we report on natural variation in gonopodium size both within and between 12 populations of the freshwater fishBrachyrhaphis episcopi(Poeciliidae) in Panama. We show that males from sites with more predatory fish species have, on average, a relatively longer gonopodium than males inhabiting sites with fewer predatory fish. Gonopodium length was not correlated with the site‐specific adult sex ratio and the average sex ratio was more strongly female biased at sites with more predatory fish. The gonopodium exhibited lower phenotypic variance than the average for sexually selected traits and it generally showed negative allometry. Our results are similar to those reported for the guppyPoecilia reticulata. Two alternative hypotheses for these findings are discussed. First, that population differences are sexually selected. Second, that they are an incidental consequence of environmental differences between sites. Specifically, that higher water flow rates select for enlarged fin size and stockier bodies in downstream sites where predatory fish are more common.

Initial stabilization preceding enhanced hemolysis in autoimmune hemolytic anemia treated with intravenous gammaglobulin

Testicular volumes of adolescents. J PEDIATR 1982;100:1010. 3. Lambert B. The frequency of mumps and mumps orchitis, and the consequences for sexuality and fertility. Acta Genet [Suppl] 1951;2:1. 4. Rundle AT, Sylvester PE. Measurement of testicular volume: its application to assessment of maturation and its use in diagnosis of hypogonadism. Arch Dis Child 1962;37:514. 5. Hurxthal LM. Hypogenitalism during the time of puberty. JAMA 1948;136:12. 6. Cassorla FG, Golden SM, Jonsonbaugh RE, et al. Testicular volume during early infancy. J PEDIATR 1981;99:742. 7. Takihara H , Sakatoky J, Fujji M, et al. Significance of testicular size measurement in andrology. I. A new orchidometer and its clinical application. Fertil Steril 1983;39:836. 8. Schonfeld WA, Bebe GW. Normal growth and variation in male genitalia from birth to maturity. J Urol 1942;48:759. 9. Schonfeld WA. Primary and secondary sexual characteristics. Am J Dis Child 1943;65:535. 10. Prader A. Testicular size: assessment and clinical importance. Triangle 1966;7:240. 11. Marshall WA, Falkner F, Tanner JM, eds. Human growth. New York: Plenum, 1978:150.

From Flies to Mice: And Back Again

Our goal in science is to generate principles of generality. Information on insects has been important in the development of our program of research on rodent reproductive behavior; I hope that the reverse effect might also be realized. Mammalian copulatory patterns can be classified with respect to locking, thrusting, multiple intromissions, and multiple ejaculations; application of a similar classification scheme might be useful with insects. In both insects and rodents variation in male genitalia and accessory glands appear correlated with reproductive behavior. Patterns of sperm competition are focal to the evolution of mating systems. Because there are important species differences in sperm competition, detailed study of both the basic pattern and the dynamics of sperm competition in a variety of species is warranted. There is evidence for female mate choice in both insects and rodents. Further, in both insects and rodents the capacity of males to produce ejaculates is limited; this implies a role for male choice in mate selection. Principles of the greatest generality will be developed if investigators can synthesize information from a wide range of taxa.