Bilateral Gynandromorph Research Articles

A bilateral gynandromorph of Aedes (Ochlerotatus) punctor (Kirby, 1837) from Germany (Diptera, Culicidae)

A completely bilateral gynandromorph of Aedes (Ochlerotatus) punctor, reared from a larva collected from a natural habitat in the German Volcanic Eifel region, is described and figured. In dorsal view, its right side is of female, the left side of male morphology. Only the external genitalia appear to be a mosaic, with male hypopygia dominating.

A gynandromorph of the stonefly Amphinemura zonata (Okamoto, 1922) (Plecoptera: Nemouridae) from Japan.

A gynandromorph of Amphinemura zonata (Okamoto, 1922) collected from Matsubara-izumi Pond in Japan is described and illustrated as the first report in the genus. The specimen exhibits bilateral gynandromorphism on abdominal sterna 79 and the paraprocts. Male features occur on the right half and female features on the left half. In addition, the gynandromorph is predominantly female as it retains female features on the dorsal male half of the abdomen, has eggs in the abdomen, has female-length fore wings, and lacks main male features such as an epiproct and a hypoproct on sternum 9.

The first case of bilateral gynandromorphic plumage type in the bearded reedling Panurus biarmicus

Bilateral gynandromorphism is a condition in which an individual has both male and female phenotypes distributed symmetrically on the body. We describe the first case of a likely gynandromorphic bearded tit, which was trapped in Poland. The bird had a black moustache and grey-blue plumage on the right side of the head, which is typical for males, and lacked this plumage coloration on the left side, which is typical of females. The entire bill was brown, consistent with a typical female, while the undertail coverts were buff with randomly distributed black spots, which represents a mixture feature of both sexes. The observation is discussed in light of earlier cases of gynandromorphic birds.

Half male half female: A rare prodigy of gynandromorphism in tasar silkworm Antheraea mylitta D (Saturniidae: Lepidoptera) with special reference to its procreative behaviour

Gynandromorphs are organisms which exhibit both male and female characteristics. This does not necessarily mean that it possesses both male and female reproductive organs, such as seen in hermaphroditic animals, as this article highlights about half- male, half female moth of Antheraea mylitta Drury spotted in Central Tasar Research and Training Institute, Ranchi, Jharkhand still expressed a female gynandromorphy in behaviour and morphologically appears to be known as a bilateral gynandromorph. This particular study has proved that genitalia of gynandromorph was similar to the female reproductive system and thus it could able to mate with normal male and that coupling has resulted in production of fertile offspring. A total of 133 eggs were laid by gynandromorph moth and 77.44% of hatching has been obtained. Longevity study showed that gynandromorph moth survived up-to 10 days. Further, the study on gynandromorphs offspring revealed that they showed normal growth and development in their life cycle and their economic characteristics has been documented.

First record of a bilateral gynandromorph of Danaus chrysippus (Linnaeus, 1758) from Mallorca (Balearic Islands, Spain) (Lepidoptera: Nymphalidae)

Danaus chrysippus (Linnaeus, 1758) was firstly reported in the Balearic Islands during the 1980s in Menorca, and in the 1990s in Mallorca. Since then several continuous reports have been documented over time. Here, in a new locality of distribution of the species in Mallorca (Balearic Islands, Spain), the first record of a bilateral gynandromorph of this species is described.

A bilateral gynandromorph of Discoelius dufourii (Hymenoptera, Vespidae, Zethinae): morphology and mating behaviour

A gynandromorph is an organism combining both female- and male-type tissues. While the vast majority of studies have described the morphology of gynandromorphs, their sexual behaviours remain under-explored. We studied a predominantly bilateral gynandromorph specimen of the predatory wasp Discoelius dufourii (Hymenoptera: Vespidae: Zethinae) reared from a trap-nest. In addition to describing the morphology, we explored the gynandromorph’s response to a conspecific female, comparing it with the behavioural interactions between normal males and females of D. dufourii and the phylogenetically related D. zonalis. For most specific behavioural elements, males of both Discoelius species exhibited a greater frequency and a higher probability of occurrences of the behaviour than did females. However, aggression and plopping behaviours were prevalent in females. The gynandromorphic specimen demonstrated behavioural activities similar to those of a male, including a relatively frequent mate body antennation and an attempt to mount a female. However, it approached the female less frequently in comparison to conspecific normal males, and it did not demonstrate substrate antennation and jumping, typical of Discoelius male mating behaviour. Based on the parameters of the nest cell, the probability of the development of the gynandromorphic specimen from an unfertilized (male) egg was higher than the probability of development from a fertilized (female) egg.

Description of a bilateral gynandromorph in Spodoptera frugiperda (Smith, 1797) (Lepidoptera: Noctuidae) from Brazil

ABSTRACT A bilateral gynandromorph of Spodoptera frugiperda was reported for the first time from Minas Gerais State, Brazil. The specimen with this trait was found among the progeny of a laboratory rearing population and exhibited dimorphism in the antennae, wings, head, thorax, and abdomen. It had a male left side and a female right side. Both the external and internal genitalia were typically those of a male.

A record of gynandromorphism in the libellulid dragonfly Crocothemis servilia (Insecta: Odonata) from India

Here we report a case of gynandromorphism in the dragonfly Crocothemis servilia (Drury, 1773), (Insecta: Odonata: Anisoptera: Libellulidae) from the Puzhakkal region of Kole wetlands, Thrissur, Kerala, southern India from a single photograph recorded during a survey conducted on 14 July 2019. The individual exhibits bilateral gynandromorphism only in the thoracic region, half of which showed blood red colouration as in males and the other half pale yellow characteristic of females. The base of the wing of the red half was marked with rich amber, in contrast with the other wing base which was paler. The head, legs, and abdomen showed typical female morphology.

Observations on a presumed bilateral gynandromorph Black Redstart Phoenicurus ochruros paired with a male

A supposed bilateral gynandromorph Black Redstart Phoenicurus ochruros in northwestern Switzerland formed a pair with a phenotypically classical male, but apparently was not breeding. The bird was documented before and after moult, when all replaced feathers were again of the same sex type. It was also recorded singing, the song being typical for the species. This is the second recorded case of a bilateral gynandromorph Black Redstart, one of only a handful cases where wild bilateral gynandromorph birds have been observed throughout the breeding season, and the first unequivocal documentation of a presumed bilateral gynandromorph bird forming a stable pair with a typical male.

The first gynandromorph of the Neotropical bee Megalopta amoena (Spinola, 1853) (Halictidae) with notes on its circadian rhythm

Gynandromorphy is an anomaly that results in an organism phenotypically expressing both male and female characteristics. Here we describe the first gynandromorph of the bee species Megalopta amoena (Spinola, 1853) (Halictidae, Augochlorini) and the second record of this anomaly within the genus Megalopta. Additionally, we analyzed the bee’s circadian rhythm, which has never before been quantified for a gynandromorph. The gynandromorph showed a deviant activity pattern; it was intermediate between that of the male and female M. amoena. Our results imply that the brains of bilateral gynandromorphs may have mixed sex-specific signaling. Based on four days of recording, the gynandromorph circadian rhythm was shifted earlier in the day relative to the male and female M. amoena, and it exhibited intensity similar to the female.

Description of Larval and Pupal Stages of a Bilateral Gynandromorph Reared from a Cross between Citheronia regalis (Fabr.) and C. splendens (Druce) (Lepidoptera: Saturniidae)

A detailed study of the larval and pupal stages of a bilateral gynandromorph obtained from a hybrid cross between Citheronia regalis (Fabr.) and C. splendens (Druce) (Lepidoptera: Saturniidae) is presented. Color illustrations and metric data document male splendens characteristics on one side and female regalis characteristics on the other side of the last instar larva. Differences in color, shape, and setal positions on the head capsule and the anal plate are documented. A video study of the larval gynandromorph is presented from a hyperlink within this publication. The pupa shows evidence of male and female genitalia, however, no asymmetry was observed among the sclerites of the antennae or of the wings. Images of the adult gynandromorph are included.

Observations of certain breeding behaviors in a bilateral gynandromorph Eastern Towhee (Pipilo erythrophthalmus)

We present observations of breeding behaviors exhibited by a bilateral gynandromorph Eastern Towhee (Pipilo erythrophthalmus) in Rhode Island during June and July 2017. The individual had the black plumage of a male towhee on the left side of its body and brownish plumage of a typical female towhee on the right side of its body. We observed this individual moving with, interacting with, and feeding fledged young. We also recorded the bird singing in similar locations over a 35 day observation period. This is one of the first observations of a free-living gynandromorph bird exhibiting certain breeding behaviors such as associating with another adult, singing, and feeding young.

A record of bilateral gynandromorphism in <i>Epeolus</i> (Hymenoptera: Apidae: Nomadinae)

The discovery of a gynandromorph of a North American Epeolus Latreille is reported. A specimen of E. flavofasciatus Smith from Flagstaff, Arizona, USA discovered in the collection of the American Museum of Natural History (AMNH) exhibits male-specific features on the left and female-specific features on the right, consistent with bilateral gynandromorphism (the first known case in the genus). Descriptions and images of the aberrant features exhibited by the specimen are presented.

Two new records of Gynandromorphs in Xylocopa (Hymenoptera, Apidae s.l.)

Two new records of gynandromorphs in Xylocopa Latreille, 1802 (Hymenoptera, Apidae). Gynandromorphs are deviant morphological individuals with genetically distinct male and female tissues. Records of sex anomalies seems to be important to better understand the mechanisms regulating phenotypic expression. Herein, two new cases of gynandromorphs in carpenter bee species of Xylocopa from Brazil are described and figured: a mixed gynandromorph of the X. (Neoxylocopa) brasilianorum (Linnaeus, 1767) from São Paulo and a bilateral gynandromorph of the X. (Neoxylocopa) ordinaria Smith, 1874 from Sergipe.

The first case of gynandry in Mygalomorphae:Pterinochilus murinus, morphology and comments on sexual behavior (Araneae: Theraphosidae)

A bilateral gynandromorph specimen of the tarantula Pterinochilus murinus Pocock, 1897 is here described and illustrated. In addition, encounters with conspecific females were studied. The possible explanations for this case of gynandry are discussed. This constitutes the first formal report of gynandry in a mygalomorph spider.

The first report of gynandromorphy in termites (Isoptera; Kalotermitidae; Neotermes koshunensis).

This is the first report of gynandromorphy in Isoptera. An Asian dry-wood termite, Neotermes koshunensis (Shiraki) [Kalotermitidae], possessing both male and female phenotypic characteristics, was found on Okinawa Island, Japan. This deformed individual showed morphological and anatomical hermaphroditism in the abdomen. The right side of the seventh sternite was the female form and contained an ovary, while the left side was the male form and contained a testis. Genotypic analysis revealed that this individual was a genotypic bilateral chimera. These results suggested that the termite was a bilateral gynandromorph with a male left side and a female right side. As reported previously in other insects, double fertilization (by two sperms, one with an X and one with a Y chromosome) of a binucleate egg is the most likely mechanism that generated this genotypic bilateral chimera. N. koshunensis has the ability to reproduce through parthenogenesis, in which the secondary polar body is likely to be used for nuclear phase recovery. If the second polar body in this mechanism has high fertility and healthy embryogenic potential, like an egg nucleus, some of gynandromorphs might be produced by a side effect of parthenogenetic ability.

Morphological outcomes of gynandromorphism in Lycaeides butterflies (Lepidoptera: Lycaenidae).

The genitalia of male insects have been widely used in taxonomic identification and systematics and are potentially involved in maintaining reproductive isolation between species. Although sexual selection has been invoked to explain patterns of morphological variation in genitalia among populations and species, developmental plasticity in genitalia likely contributes to observed variation but has been rarely examined, particularly in wild populations. Bilateral gynandromorphs are individuals that are genetically male on one side of the midline and genetically female on the other, while mosaic gynandromorphs have only a portion of their body developing as the opposite sex. Gynandromorphs might offer unique insights into developmental plasticity because individuals experience abnormal cellular interactions at the genitalic midline. In this study, we compare the genitalia and wing patterns of gynandromorphic Anna and Melissa blue butterflies, Lycaeides anna (Edwards) (formerly L. idas anna ) and L. melissa (Edwards) (Lepidoptera: Lycaenidae), to the morphology of normal individuals from the same populations. Gynandromorph wing markings all fell within the range of variation of normal butterflies; however, a number of genitalic measurements were outliers when compared with normal individuals. From these results, we conclude that the gynandromorphs’ genitalia, but not wing patterns, can be abnormal when compared with normal individuals and that the gynandromorphic genitalia do not deviate developmentally in a consistent pattern across individuals. Finally, genetic mechanisms are considered for the development of gynandromorphism in Lycaeides butterflies.

Observations of a Bilateral Gynandromorph Northern Cardinal (Cardinalis cardinalis)

We describe behavioral observations of a bilateral gynandromorph Northern Cardinal (Cardinalis cardinalis) in northwestern Illinois from December 2008 through March 2010. The bird exhibited the typical bright red color of a male cardinal on the left half of its body, and the dull brownish-gray appearance of a female cardinal on the right half. We observed the bird more than 40 days, mostly in the vicinity of bird feeders. It was never paired with another cardinal, was never heard vocalizing, and was not subjected to any unusual agonistic behaviors from other cardinals. These observations are among the most extensive of any bilateral gynandromorph bird in the wild.

HINTW, a W‐chromosome HINT gene in chick, is expressed ubiquitously and is a robust female cell marker applicable in intraspecific chimera studies

Grafting and transplantation experiments in embryology require proper distinction between host and donor tissues. For the avian model this has traditionally been achieved by using two closely related species (e.g., chick and quail) followed by species-specific antibody staining. Here, we show that an in situ hybridization probe against the HINTW gene is a robust and reliable marker for female-derived chicken cells. At all pre-circulation stages tested, all cells in female embryos, independently confirmed by PCR analysis, were strongly positive for HINTW, whereas all male embryos were negative. This probe is broadly applicable in intra-specific chick/chick chimera studies, and as a proof of principle, we utilized this probe to detect female cells in three experimental settings: (1) to mark female donor cells in a node transplantation assay; (2) to distinguish female cells in male/female twins generated by the Cornish pasty culture; and (3) to detect female half of the embryo in artificially generated bilateral gynandromorphs. A rapid, PCR based pre-screening step increases the efficiency of obtaining desired donor/host sex combination from 25% to 100%. For most avian chimera studies, this female-specific in situ probe is a low cost alternative to the commonly used QCPN antibody and to ubiquitous-GFP chicken strains which are not widely available to the research community.

New orchid and leaf-cutter bee gynandromorphs, with an updated review (Hymenoptera, Apoidea)

Two new cases of gynandromorphs in bees are described and figured: a mixed, nearly bilateral gynandromorph of the orchid bee Euglossa (Euglossa) tridentata Moure and a mixed gynandromorph of the megachilid bee Megachile (Chelostomoides) otomita Cresson. Records of gynandromorphic bees recently documented in the literature are also summarized. In less than a decade, more than 20 new cases were documented in 15 species and five genera previously unknown; as of today, gynandromorphs are recorded from 113 species in 29 genera of all bee families. Most gynandromorphs have been recorded from the long-tongued bee families Apidae and Megachilidae, but at the generic level, a significant percentage of species are from the megadiverse Megachile s.l. (23% of the total) and Andrena (14%) (Andrenidae). Although gynandromorphs are known from all major biogeographic regions of the world, most are recorded from the Holarctic region (79%) (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)