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1.
Abstract
The tribe Heteronycini and 10 included genera (4 of them new) are defined. A key to genera and keys to species of Acheilo gen. n. and Webbella gen. n. are provided. The new genera are: Acheilo, Paraheteronyx, Proborhinus and Webbella. A. clypeatus gen. n., sp. n. is described.
The following species are transferred to other genera: Heteronyx bravicollis Blackburn, H. brevicoxis Lea, H. clypealis Lea, H. cribrifrons Lea, H. inconstans Lea, H. noctivagus Lea, H. phanophilus Lea, H. transversopolitus Lea and H. unidentatus Lea to Neoheteronyx Blackburn; H. unguiculatus Burmeister to Paraheteronyx gen. n.; H. cornutus Blackburn to Proborhinus gen. n.; H. capitalis Blackburn and H. pedarius Blackburn to Acheilo gen. n.; H. firmus Blackburn and H. labralis Blackburn to Webbella gen. n. Anacheirotus Blackburn is synonymised with Heteronyx Guérin-Méneville; A. inornatus Blackburn becomes H. inornatus (Blackburn). Pseudoheteronyx seticollis Lea is synonymised with P. creber Blackburn. Heteronyx clypealis Lea is synonymised with Neoheteronyx brevicollis (Blackburn). Lectotypes are designated for Heteronyx unguiculatus and Eurychelus marmoratus Blanchard.  相似文献   

2.
Courtship behaviors are androgen-dependent in many vertebrates and castration often decreases courtship. We examined the effectiveness of castration in reducing courtship behaviors and 11-ketotestosterone (KT) and testosterone (T) in restoring them in male white perch. Castrates were given implants containing KT, T or no hormone. Sham-operated males received implants without hormone. Three weeks later, males were exposed to an ovulated female for 1 h and two courtship behaviors were quantified. Attending behavior involves close and continuous following of a female with occasional contact. Circling involves rapid transits around the female in a circular pattern or back and forth in front of her. In plasma samples taken immediately after observations, KT and T were below detectable levels in castrated males but at high physiological levels in males implanted with KT or T. Castrated males given KT attended females more than castrated males given T implants or implants containing no hormone, but not more than sham-operated males. Circling was eliminated by castration but restored by implantation with T or 11-KT to values exhibited by sham-operated males. This is one of the few demonstrations that KT can regulate courtship behavior in a non-territorial and economically important fish species.  相似文献   

3.
We have investigated the biochemical properties of Xenopus laevis p53. With an in vitro binding assay, we can detect a specific association between X. laevis p53 and simian virus 40 large T antigen. Furthermore, X. laevis p53 expressed in monkey COS cells is stably associated with this viral antigen. Like mammalian p53, X. laevis p53 in complex with simian virus 40 large T antigen exhibits a 20-fold increase of its half-life. On the other hand, X. laevis p53 is unable to associate either in vivo or in vitro with adenovirus type 5 E1B 55-kilodalton protein. We show by an immunological technique that X. laevis p53 forms specific complexes with mammalian hsp72 and hsp73 heat shock proteins only at a temperature well above the optimal growth temperature for X. laevis. Our results suggest that the protein-binding properties of p53 are closely related to the functional activity of the protein.  相似文献   

4.
Abstract
Final-instar larvae, pupae and adults of Cestrinus trivialis Erichson from south Queensland are described and illustrated. Characters are given which allow the species to be separated from Gonocephalum macleayi (Blackburn), Pterohelaeus darlingensis Carter, and P. alternatus Pascoe.  相似文献   

5.
We consider haploid and dioecious age-structured populations that vary over time in cycles of length k. Results are obtained for both autosomal and sex-linked loci if the population is dioecious. It is assumed that k is small in comparison with numbers of haploid individuals (or of numbers of males and females) in any generation of a cycle. The inbreeding effective population size N(e) is then approximately given by the expression [T summation operator (k-1)(j=0)1/[N(e)(j)T(j)]](-1), where N(e)(j) and T(j) are, respectively, the effective population size and generation interval that would hold if the population was at all times generated in the same way as at time j. The constant T, which is the effective overall generation interval, is defined to be k times the harmonic mean of the quantities T(j). Our expressions for T and N(e), in terms of N(e)(j) and T(j), are general, but the N(e)(j)s are derived under the assumption that offspring are produced according to Poisson distributions.  相似文献   

6.
Courtship behaviors are androgen-dependent in many vertebrates and castration often decreases courtship. We examined the effectiveness of castration in reducing courtship behaviors and 11-ketotestosterone (KT) and testosterone (T) in restoring them in male white perch. Castrates were given implants containing KT, T or no hormone. Sham-operated males received implants without hormone. Three weeks later, males were exposed to an ovulated female for 1 h and two courtship behaviors were quantified. Attending behavior involves close and continuous following of a female with occasional contact. Circling involves rapid transits around the female in a circular pattern or back and forth in front of her. In plasma samples taken immediately after observations, KT and T were below detectable levels in castrated males but at high physiological levels in males implanted with KT or T. Castrated males given KT attended females more than castrated males given T implants or implants containing no hormone, but not more than sham-operated males. Circling was eliminated by castration but restored by implantation with T or 11-KT to values exhibited by sham-operated males. This is one of the few demonstrations that KT can regulate courtship behavior in a non-territorial and economically important fish species.  相似文献   

7.
Abstract The Pepila fuscomaculata species-group from Australia, including P. fuscomaculata ( Baly 1877 ), P. hypocrita ( Blackburn 1896 ), P. submetallescens ( Baly 1877 ), P. tumbyensis ( Blackburn 1896 ), P. blackburni sp. n., P. brittoni sp. n., P. nikitini sp. n. and P. reidi sp. n., is analysed. A key to all the species is presented. Line drawings of male and female genitalia of all species are included. Brief ecological and zoogeographical data are also reported.  相似文献   

8.
The number of muscle fibers in the vocal organ of the adult male African clawed frog, Xenopus laevis, exceeds that of adult females. This sex difference is the result of rapid fiber addition in males between the end of metamorphosis, post-metamorphic stage 0 (PM0) and PM2. At PM0, male and female frogs have similar numbers of laryngeal muscle fibers. Males then add more muscle fibers than females and achieve an adult value that is 1.7 times the female number. Males castrated at PM0 have the same fiber number as females. Ovariectomy at PM0 does not alter muscle fiber addition in females. Gonadectomy at PM2 has no effect on fiber addition in either sex. Females attain masculine muscle fiber number if their ovaries are replaced with a testis at metamorphosis. Exogenous testosterone treatment at PM0 significantly increases fiber number in females but not in males. Exogenous testosterone given at PM2 has no effect on fiber number in females but decreases fiber number in males. We conclude that the testes are necessary for the marked addition of laryngeal muscle fibers seen in male X. laevis between PM0 and PM2. The masculine pattern of muscle fiber addition can be induced in females provided with a testis. Androgen secretion from the testes most probably accounts for masculinization of laryngeal muscle fiber number. After PM2, androgens are no longer necessary for muscle fiber addition and cannot increase fiber number in females.  相似文献   

9.
10.
The synthetic progestin, medroxyprogesterone acetate (MPA), is used to treat male sex offenders, and it is also suppresses sexual activity in male monkeys. To examine the possibility that MPA may act as an anti-androgen in the primate brain, 4 intact male cynomolgus monkeys were given MPA (40 mg i.m.) once a week for 16 weeks, while 4 control males received i.m. injections of vehicle. All males were then castrated and 3 days later were given 3 mCi [3H]testosterone ([3H]T) i.v.; 1 h after injection males were killed, and radioactivity in nuclear pellets obtained from the hypothalamus (HYP), preoptic area (POA), amygdala (AMG), septum, pituitary gland and genital tract was analyzed by HPLC. Concentrations of [3H]T and [3H]dihydrotestosterone in nuclear pellets were 65-96% lower in MPA-treated males than in controls (P less than 0.001), but the aromatized metabolite, [3H]estradiol, which was the major form of radioactivity present in nuclear pellets from HYP, POA and AMG, was unchanged. There were no differences in concentrations of [3H]T in supernatants from the tissues of MPA-treated and control males. Because the reduced nuclear uptake of androgen in brain occurred in males whose androgen-dependent behavior had been suppressed by MPA treatments, it is proposed that MPA may have anti-androgenic effects at the level of the cell nucleus in brain regions that control behavior.  相似文献   

11.
Abstract  Cuticular hydrocarbon components in beetles of six Australian melolonthines whose larvae damage sugarcane, Antitrogus parvulus (Britton), A. consanguineus (Blackburn), Lepidiota negatoria (Blackburn), L. picticollis (Lea), L. noxia (Britton) and Dermolepida alborhirtum (Arrow), are identified and compared. These species demonstrate species-specific cuticular hydrocarbon profiles with a number of unprecedented structures. Major components have been identified as polymethylated hydrocarbons, 3-methyl substituted n -alkanes, 9,10-allenes and the corresponding C9 alkenes. The similarity of these compounds shows some correlation with the phylogeny of the beetles, but two polymethylated C22 hydrocarbons are unique to A. parvulus. One C25 allene is shown to have a potential role in mate recognition in A. consanguineus.  相似文献   

12.
Abstract  Species of the Australian genus Myrabolia are reviewed. Lectotypes are designated for Silvanus brevicornis Erichson, Myrabolia haroldiana Reitter, M. lindensis Blackburn and M. longicornis Blackburn. The following new species are described and illustrated: M. australis, M. blackburni , M. elongata , M. kioloa , M. lawrencei , M. micra , M. pelion and M. tasmanica. Ocholissa leai Grouvelle, originally described in Colydiidae, is here transferred to Myrabolia as M. leai (Grouvelle) comb. n. The nomenclatural history, a diagnosis and distribution data are provided for each species. A key to the species of the genus is presented.  相似文献   

13.
Salt marsh plants were tested for their insecticidal activities against larvae of the confused flour beetle Tribolium confusum (Tenebrionidae). 16 aerial part extracts were obtained using organic solvents of increasing polarity and tested for their anti-feedant and toxicity effects. Responses varied with plant material and extract type. Ethyl acetate extracts of F. laevis, S. echioides and. T. boveana and petroleum ether extract of F. laevis presented, anti-feedant property. However, S. fructicosa seemed to be attractive to the tested flour beetle. Mortalities of 97, 87, 97 and 80% were observed by using respectively ethyl acetate extracts of F. laevis, S. echioides and T. boveana and petroleum ether extract of F. laevis, when applied at a dose of 1%, mixed with the insect diet. This preliminary study showed that F. laevis, S. echioides and T. boveana presented potential bio-insecticidal activity with ethyl acetate extracts, similar result was found with petroleum ether extract of F. laevis. More complementary studies are needed for the use of these extracts to control T. confusum.  相似文献   

14.
15.
16.
Male Glossina sexually sterilized by gamma-irradiation are as efficient vectors of trypanosomiasis as fertile males. An attempt was made, using isometamidium chloride (Samorin), to interfere with the cyclical development of trypanosomes in sterile males, destined for use in the sterile insect release (SIR) method of tsetse eradication. The infection rate with mature Trypanosoma congolense Broden was effectively reduced in sterile male Glossina morsitans centralis Machado, when the flies were fed on an infected goat 2 days after they were fed as tenerals on an in vitro bloodmeal containing 8 micrograms Samorin/ml blood. The infection rates with mature T.vivax Ziemann and T.brucei brucei Plimmer & Bradford were completely suppressed at this drug dose. Whensterile teneral males were fed on a bloodmeal containing 12 micrograms/ml Samorin and given the infected bloodmeal 10 days later, infections by mature T.vivax, T.congolense and T.b.brucei were completely suppressed. Hence in the management of a tsetse eradication programme utilizing the SIR method, it is recommended that the sterile teneral male tsetse should, prior to release, be given a bloodmeal containing Samorin at 12-15 micrograms/ml blood. This will effectively suppress future disease transmission.  相似文献   

17.
The feet of 259 new patients at a chiropody clinic were examined for tinea pedis, onychomycosis, and erythrasma: 23% of men and 4% of women were infected by dermatophytes, and the nails of seven males were infected by non-dermatophytes. Of 200 patients examined under Wood''s light 37% showed the coral-red fluorescence of erythrasma.Of the 259 patients, 9.7% were infected by Trichophyton interdigitale, 2.7% by T. rubrum, and 1.5% by Epidermophyton floccosum. Reasons are given, based on the method of selection of the patients, for supposing that T. interdigitale is still the dominant cause of tinea pedis in the population at large, despite figures from dermatological clinics suggesting the dominance of T. rubrum. The high incidence of infection in males compared with females corresponds with similar findings in school-children.  相似文献   

18.
Neural crest-derived melanophores form species-specific patterns in the dermis of amphibian embryos. Melanophore patterns may be generated by one of two general mechanisms: pigment cell precursors disperse throughout the embryo, with melanophores differentiating in certain regions due to environmental cues, or melanoblasts may localize in different regions as a result of a hierarchy of tissue affinities. Both of these mechanisms have been proposed to be responsible for the dorso-ventral patterning of melanophores in Xenopus laevis. We have reexamined the distribution of melanoblasts in X. laevis and Taricha torosa using the dopa (3,4-dihydroxyphenyl-alanine)-staining technique. We have found that many of the dopa-positive cells identified as melanoblasts by some researchers are actually not derived from the neural crest: dopa-positive cells in T. torosa were identified in the transmission electron microscope to be either leukocytes or erythrocytes, in X. laevis dopa-positive cells are found between the ectoderm and somites where neural crest cells are not found, and X. laevis embryos surgically depleted of neural crest have dopa-staining patterns identical to control embryos. Melanoblasts are apparently not found in the ventralmost regions of early T. torosa and X. laevis embryos, providing additional evidence for the role of differential tissue affinities in directing the formation of embryonic pigment cell patterns.  相似文献   

19.
The possible mechanisms by which the administration of drugs may alter the gonadal function in humans are considered in this review. Based on personal data, and on data published in the literature, the following events may occur: (1) blockade of gonadal steroidogenesis; (2) interaction of drug(s) with the steroid-binding protein system in plasma, and (3) interference of drug(s) at the level of the feedback control of gonadotropin secretion. Representative examples of the above mechanisms are as following: (1) Ketoconazole possesses inhibitory effects in vitro on cytochrome P-450. When given in adult males, it decreased the plasma concentrations of testosterone (T) and androstenedione and increased 17 alpha-hydroxyprogesterone levels, suggesting that this drug acts in vivo on gonadal steroidogenesis by blocking the 17,20-lyase. (2) Danazol is a progestagen with high affinity for sex steroid-binding protein (SBP); when given in high dosages in normal males, it increased rapidly the dialyzable fraction (percent protein unbound or free fraction) of T. This suggests that by interacting with the binding sites of SBP, danazol and/or its metabolites displace the fraction of T bound to SBP. However, in males as well as in females, the long-term administration of danazol decreased also the binding capacity of SBP, and consequently increased the free fraction of sex steroid hormones. (3) Dihydrotestosterone (DHT), the most active androgen in many target cells, given at therapeutic dosages to adult males, resulted in a decrease in plasma concentrations of luteinizing hormone (LH) and T, without any significant change in the percent of free T, even though the affinity of DHT for SBP is higher than that of T. This suggests that the main effect of DHT is to inhibit gonadotropin secretion at the central level. (4) Flutamide, a nonsteroidal antiandrogen, increased both LH and T levels, demonstrating its pure antiandrogenic activity on gonadotropin secretion. The consequence(s) of the effects of such drugs on the production, the metabolic clearance rate and the bioavailability of sex steroid hormones are discussed.  相似文献   

20.
A number of man-made chemicals has been shown to mimic endogenous hormones and to induce alterations of reproductive physiology in wild populations. Of particular importance are compounds that mimic estrogens and androgens (and their antagonists), because of their central role in reproductive function. In this study, male and female adult South African clawed toads (Xenopus laevis) were exposed to ethinylestradiol (EE2), tamoxifen (TAM), methyldihydrotestosterone (MDHT) and flutamide (FLU) as (anti)estrogenic and (anti)androgenic model compounds, respectively, at a concentration of 10(-8) M, and to water from the river Lambro (LAM), a contaminated watercourse from Northern Italy. Potential disrupting effects on reproduction were studied by histological analyses of gonads. The strongest adverse effects were observed in EE2 and LAM exposed males, e.g. tubule mean diameter reduction, spermatogenic nest breakdown and interlobular wall thickening. In both groups, the occurrence of small oocytes within the seminiferous tubules was observed. In TAM and MDHT exposed females slight oocyte atresia and occurrence of spermatogenic nests were observed. In contrast to previous studies addressing the alteration of molecular biomarkers in the same experimental setup, histological analyses of gonads were very sensitive and indicated an adverse effect of water from Lambro River on reproductive physiology of X. laevis.  相似文献   

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