17 research outputs found

    Dramatic Dietary Shift Maintains Sequestered Toxins in Chemically Defended Snakes

    Get PDF
    Unlike other snakes, most species of Rhabdophis possess glands in their dorsal skin, sometimes limited to the neck, known as nucho-dorsal and nuchal glands, respectively. Those glands contain powerful cardiotonic steroids known as bufadienolides, which can be deployed as a defense against predators. Bufadienolides otherwise occur only in toads (Bufonidae) and some fireflies (Lampyrinae), which are known or believed to synthesize the toxins. The ancestral diet of Rhabdophis consists of anuran amphibians, and we have shown previously that the bufadienolide toxins of frog-eating species are sequestered from toads consumed as prey. However, one derived clade, the Rhabdophis nuchalis Group, has shifted its primary diet from frogs to earthworms. Here we confirm that the worm-eating snakes possess bufadienolides in their nucho-dorsal glands, although the worms themselves lack such toxins. In addition, we show that the bufadienolides of R. nuchalis Group species are obtained primarily from fireflies. Although few snakes feed on insects, we document through feeding experiments, chemosensory preference tests, and gut contents that lampyrine firefly larvae are regularly consumed by these snakes. Furthermore, members of the R. nuchalis Group contain compounds that resemble the distinctive bufadienolides of fireflies, but not those of toads, in stereochemistry, glycosylation, acetylation, and molecular weight. Thus, the evolutionary shift in primary prey among members of the R. nuchalis Group has been accompanied by a dramatic shift in the source of the species’ sequestered defensive toxins

    Description of the final-instarlarva and pupa of Acanthacorydalis orientalis (McLachlan, 1899) (Megaloptera: Corydalidae) with some life history notes

    No full text
    Cao, Chengquan, Liu, Xingyue (2013): Description of the final-instarlarva and pupa of Acanthacorydalis orientalis (McLachlan, 1899) (Megaloptera: Corydalidae) with some life history notes. Zootaxa 3691 (1): 145-152, DOI: 10.11646/zootaxa.3691.1.

    Two new species of the genus Xya Latreille, 1809 (Orthoptera, Tridactyloidea, Tridactylidae) from Yunnan with a key to all Xya species in China

    No full text
    This contribution to the taxonomy of Xya Latreille, 1809 (Orthoptera, Tridactyloidea, Tridactylidae) adds descriptions and photographic illustrations of two new species: Xya xishangbanna sp. nov. and Xya yunnanensis sp. nov. from Xishuangbanna, Yunnan Province, China. Xya xishangbanna sp. nov. can be diagnosed by the shiny dark brown hind femora, and the epiproct with a shallow bottom of the middle “v-shaped” crack in the upper part and straight sides; Xya yunnanensis sp. nov. can be diagnosed by the compound eye bearing no narrow band along the inner margin, and the epiproct with the bottom of the side edge with a sharply angled protrusion and a narrow lower anchor-shaped base less than 1/2 the width of the upper one. Distributional information and bionomics for these two new species and photos for the habitat are given. A key to all Chinese species of Xya is provided

    Allometry and morphological trait relationship in the sexually dimorphic Chinese dobsonfly, Acanthacorydalis asiatica (Wood-Mason, 1884) (Megaloptera, Corydalidae)

    No full text
    Male insects with large weapons such as horns and elongate mandibles would be expected to invest more on such structures than other parts of the body for advantages in male to male competition for mating. In male genitalia, however, intermediate size provides a better fit for more females than small or large sizes, and such a male would leave more offspring regardless of their body size. These predictions were tested using a static allometry analysis between body size and other trait sizes. Acanthacorydalis asiatica is a large dobsonfly (Megalotera) and males have conspicuously large mandibles used as weapons. We examined the hypothesis that the male mandibles of this sexually dimorphic species are sexually selected to enlarge, whereas the male genitalia are stable to be intermediate regardless of a great variation in body size. The results, as predicted, showed positive allometry between male body size and mandible length but negative allometry between male body size and ectoproct length (a male grasping structure). Sperm are transferred through a small spermatophore attached externally to the female genital opening, so it may be evolutionarily unnecessary to develop an enlarged male genital size. In contrast, there may be a trade-off between male mandible size and wing length, because of negative allometry between body size and wing length in males but isometry between them in females

    Adults of Alderflies, Fishflies, and Dobsonflies (Megaloptera) Expel Meconial Fluid When Disturbed

    No full text
    Chemical secretions are an effective means by which insects may deter potential enemies, already being studied extensively with regard to their chemicals, synthesis, toxicity, and functions. However, these defensive secretions have been little studied in Megaloptera. Herein, the fluid expelling behavior of adult alderflies (Sialidae), fishflies (Corydalidae: Chauliodinae), and dobsonflies (Corydalidae: Corydalinae), all of the order Megaloptera, is described in detail regarding the timing and possible function of this behavior. When disturbed artificially, both males and females could expel fluid from the anus. However, the frequency of expelling was much lower in alderflies than in fishflies and dobsonflies. The amount of expelled fluid relative to body weight was also smaller in alderflies. In fishflies and dobsonflies, the amount of expelled fluid decreased with adult age, probably because the fluid is little replenished once expelled. The cream-colored fluid seems to be meconial fluid produced via the Malpighian tubules at the pupal stage, which is usually discharged at adult emergence in most other holometabolous insects. However, adult fishflies and dobsonflies often expel it vigorously by bending their abdomen when disturbed after emergence. Thus, the fluid expelling may be an anti-predatory behavior, particularly in younger adults that can expel a relatively large amount of fluid

    First report of the Old World leafhopper genus Olidiana McKamey (Hemiptera Cicadellidae: Coelidiinae) from Pakistan with description of a new species

    No full text
    Naveed, Hassan, Wang, Xiu-Dan, Cao, Chengquan, Zhang, Yalin (2020): First report of the Old World leafhopper genus Olidiana McKamey (Hemiptera Cicadellidae: Coelidiinae) from Pakistan with description of a new species. Zootaxa 4778 (2): 396-400, DOI: https://doi.org/10.11646/zootaxa.4778.2.1

    Metastatic breast cancer to the thyroid diagnosed by fine-needle aspiration cytology: A case report and literature review

    No full text
    Metastatic breast cancer to the thyroid is rare. We report a case of breast cancer that metastasized to bilateral thyroid. A 62-year-old woman who was admitted due to thyroid nodules identified by ultrasound. Ultrasound revealed multiple thyroid nodules with calcification, which were classified as TI-RADS 4c. She had a history of left breast cancer 5 years ago, treated with radical mastectomy and adjuvant EC-TH chemotherapy and radiotherapy. The patient underwent fine-needle aspiration of bilateral thyroid nodules, and the cytology examination revealed a metastatic ductal carcinoma of breast. The findings indicate that cytological morphology, immunohistochemistry and molecular test are important for diagnosis of thyroid metastatic carcinoma

    Checklist and keys to Deltocephalinae leafhoppers (Hemiptera, Cicadellidae) from Pakistan

    No full text
    Keys to all levels of the subfamily Deltocephalinae (Hemiptera: Cicadellidae) of Pakistan are provided based on published records and original data from recent research. Checklists to the genera and species of Deltocephalinae are also given. A total of 49 genera with more than 100 species are now known from Pakistan. Two new synonyms are proposed, i.e., Cicadulina striata Ahmed, 1986 a junior synonym of Cicadulina chinai Ghauri, 1965, syn. nov. and Macrosteles parafalcatus Naveed & Zhang, 2018 a new junior synonym of Macrosteles indrina (Pruthi, 1930), syn. nov

    Description of the final-instar larva and pupa of Neoneuromus ignobilis Navás, 1932 (Megaloptera: Corydalidae)

    No full text
    Cao, Chengquan, Liu, Fangqing, Tong, Chao, Fang, Yaqian, Li, In, Liu, Ingyue (2018): Description of the final-instar larva and pupa of Neoneuromus ignobilis Navás, 1932 (Megaloptera: Corydalidae). Zootaxa 4378 (4): 581-588, DOI: https://doi.org/10.11646/zootaxa.4378.4.

    First description and bionomic notes for the final-instar larva and pupa of an Oriental dobsonfly species, Neoneuromus sikkimmensis (van der Weele, 1907) (Megaloptera: Corydalidae)

    No full text
    Neoneuromus van der Weele, 1909, a member of megalopteran subfamily Corydalinae, is a common and widespread dobsonfly genus of the Oriental Region. The adult taxonomy of Neoneuromus is relatively well-known but the larvae and pupae are undescribed. In this paper we describe the last-instar larva and the pupa of N. sikkimmensis (van der Weele, 1907), representing the first detailed description of any immature stage of Neoneuromus. Information on the bionomics of this species is also reported
    corecore