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Background
Wolbachia are endosymbiotic bacteria that commonly infect numerous arthropods. Despite their broad taxonomic distribution, the transmission patterns of these bacteria within and among host species are not well understood. We sequenced a portion of the wsp gene from the Wolbachia genome infecting 138 individuals from eleven geographically distributed native populations of the fire ant Solenopsis invicta. We then compared these wsp sequence data to patterns of mitochondrial DNA (mtDNA) variation of both infected and uninfected host individuals to infer the transmission patterns of Wolbachia in S. invicta. 相似文献3.
Longidorus kheirii n. sp., a parthenogenetic species, was found in soil samples collected from the rhizosphere of Rosa sp. growing in a natural mountainous region close to Maragheh city, northwestern Iran. It is characterised by having a long body (6.7-9 mm), a 19.5-23 mum wide head continuous with the body contour, a truncate and slightly concave lip region with convex sides between the anterior end and the guide-ring, an odontostyle 113-130 mum long, an odontophore 69-97.5 mum long, a body width of 90.5-117.5 mum at the mid-body, a long, wide oesophageal bulb (149.5-193.5 x 39.5-48 mum), a tail length of 47-72 mum, a male with 11 ventromedian supplements and spicules of 85 mum in length, and four juvenile stages. The ribosomal 18S rDNA gene of L. kheirii n. sp., L. leptocephalus Hooper, 1961, L. profundorum Hooper, 1966 L. euonymus Mali & Hooper, 1973 and two unidentified species listed as Longidorus sp. 1 and Longidorus sp. 2, all recovered from northwestern Iran in the same survey, and the ITS1 of L. kheirii n. sp. and Longidorus sp. 1 were sequenced in order to investigate the phylogenetic relationships with other previously sequenced Longidorus species. 相似文献
4.
Summary Male inhibition of female re-mating is com-mon in many insects. Mating plugs, used by males
to con-trol female re-mating, have been postulated in several ant species. Recent studies of
bumblebees have described re-mating inhibition by male accessory gland secretions. Fire
ants Solenopsis invicta possess accessory glands containing
the same four fatty acids as do the bumblebees. Furthermore it appears that some of these acids
are transferred to the female at mating. Thus, it is possible that single mating of fire ant
females may be enforced by male mating plugs. 相似文献
5.
Giuseppe Mazza Francesco Paoli Agostino Strangi Giulia Torrini Leonardo Marianelli Giuseppino Sabbatini Peverieri Francesco Binazzi Giovanni Bosio Stefano Sacchi Claudia Benvenuti Davide Venanzio Emanuela Giacometto Pio F. Roversi George O. PoinarJr. 《Systematic parasitology》2017,94(8):915-926
A new species of mermithid nematode, Hexamermis popilliae n. sp. (Nematoda: Mermithidae) is described from the Japanese beetle Popillia japonica Newman in Italy, an area of new introduction for this invasive pest. The combination of the following characters separates H. popilliae from other members of the genus Hexamermis Steiner, 1924: adult head obtuse; amphidial pouches slightly posterior to lateral head papillae in female but adjacent to lateral head papillae in males; amphidial openings large, well developed; amphidial pouches elliptical in females and oblong in males; cuticular vulvar cone well developed, vulvar lips greatly reduced or lacking, vagina curved at tip where meeting uteri, without reverse bend (not S-shaped), spicules slightly curved, with a slight bend in the basal portion, approximately equal to body width at cloaca. This is the first record of a species of Hexamermis parasitizing the Japanese beetle Popillia japonica. The only previous mention of mermithid nematodes from P. japonica was an undescribed species of Psammomermis in North America. Hexamermis popilliae will be evaluated as a potential biological control agent in an integrated control program of the Japanese beetle in Italy. 相似文献
6.
Nest structure in ants is often designed to optimize the colony’s ability to thermoregulate, and this specialization is most
highly developed in mound-building ant species. Solenopsis invicta invest a large amount of energy in building mounds and transporting their brood up and down in their nests as a means of
thermoregulation. Because few ant species build true mounds, we wanted to determine the effectiveness of these mounds in harvesting
solar heat as well as to distinguish what factors (temperature vs. circadian rhythm) govern where fire ants place their brood
in the mound and when they place it. We measured temperature patterns in the mound over several days at different depths and
under different conditions (under direct sunlight or shade), and then conducted a series of field experiments to manipulate
the orientation and time of heating.
On cool mornings in spring or fall, surface temperatures of the mound rise at the fastest rate on the side receiving the most
direct sunlight (usually the south side). This heating causes a temperature gradient through different depths in the mound,
and shows little difference from outside ground temperature at a depth greater than ~40 cm inside the nest. In the morning,
fire ants move their brood up into the mound on the side most directly heated, and when temperatures exceed optimal (~32°C)
they move their brood down the temperature gradient to lower depths in the nest. In addition to this, mound temperature does
not only increase due to direct sunlight, but temperature also increases higher than ground temperatures when the mound is
in the shade due to its low specific heat.
Experiments in which sunlight was mirrored to the normally shaded side of the mound, or when mounds were heated at night,
revealed that S. invicta primarily track temperature patterns and do not rely on behavioral habits or circadian rhythms for the thermoregulatory transport
of their brood. When mounds were shaded, S. invicta brood was evenly distributed directly under the surface of the mound rather than aggregating towards a specific side. The
fire ant mound is important for thermoregulation because, compared to moundless subterranean nests, it absorbs heat more rapidly
both in direct sunlight and shady conditions. Temperature tracking within the nest is key to understanding thermoregulatory
placement of fire ant brood, as well as insight into the production of sexual brood and reproduction.
Received 9 August 2007; revised 31 January 2008; accepted 7 February 2008. 相似文献
7.
Summary Larvae pass through five instars in the temperate, subterranean ponerine ant, Amblyopone silvestrii. Field colonies displayed a large decrease in the number of eggs during mid-summer, despite the fact that queens maintained fully developed ovaries with mature eggs. Observations of laboratory colonies indicate that cannibalism by 1st and 2nd instar larvae caused this decrease in egg number. These instars consumed a total of 66–75% of eggs in the nest, with each larva consuming 2–3 eggs before molting to the 3rd instar. At that time the larvae began to feed on arthropods. The preferred prey of A. silvestrii consists of entire centipedes; the large size of these prey items relative to the size of early instar larvae makes it difficult for the larvae to feed on these prey. Additionally, workers of A. silvestrii do not engage in oral trophallaxis. Consequently, oophagy is a plausible method to feed these very small larvae. 相似文献
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Inter- and intracellular cysts from a presumed single species, Myxobolus procerus (Kudo, 1934), parasitising the trout-perch Percopsis omiscomaycus were compared with respect to their spore morphology and small subunit 18S ribosomal DNA. The two cyst types have similar pyriform spores and comparable ranges in spore length and width, size of the polar capsules and number of filament coils. However, fixed spores of the intracellular cysts are significantly shorter (p < 0.05) in mean length than those from intercellular cysts, giving them a broader appearance. Comparing 991 base pairs of 18S rDNA revealed a 20 bp difference between the two cyst types (97.9% similarity), 10 due to base substitutions and 10 due to the presence or absence of a base. The described morphological differences and consistent 2.1% difference in the 18S rDNA reveal that the intracellular form is a separate species, which is described herein as Myxobolus intramusculi n. sp. M. intramusculi n. sp. and M. procerus may be sister species and it is suggested that the two species arose through sympatric speciation involving a switch in site specificity within a single host species. 相似文献
10.
A new genus and species of tetradonematid nematode, Myrmeconema neotropicum n. g., n. sp., is described from larval, pupal and adult stages of Cephalotes atratus L. (Hymenoptera: Formicidae) in Peru and Panama. Diagnostic characters of the new genus include: males and females subequal in size; cuticle with minute annulations; six cephalic papillae; stylet present in all stages; stichocytes absent; trophosome degenerate; three penetration glands; gonads paired and opposite; vulva in mid-body region; single spicule; genital papillae absent; adult tails rounded; infective juveniles moult once in egg; and adults of both sexes remain in the host throughout their development. As the female nematodes mature inside the worker ants, the host gasters change colour from black to red. 相似文献
11.
Two species of nematodes, Angiostoma coloaense n. sp. and Aulacnema monodelphis n. g., n. sp. (Angiostomatidae: Rhabditida) are described from terrestrial molluscs of Vietnam. Both species are characterised by a long bowl-shaped buccal cavity and typically angiostomatid male bursal alae, spicules and gubernaculum. The new genus, Aulacnema n. g., is erected for the first reported monodelphic angiostomatid. Angiostoma coloaense n. sp. can be distinguished from other species of Angiostoma Dujardin, 1845 by having a buccal cavity length greater than its width and the absence of tail spikes on both males and females. 相似文献
12.
Animals grow and optimize performance when they collect foods in amounts and ratios that best meet their species-specific
nutritional requirements. For eusocial organisms like ants, where only a small fraction of the colony members collect food,
increasing evidence demonstrates that strong macronutrient regulation occurs at the colony level. Here, we explored regulation
of protein and carbohydrate (p:c) intake in the Rasberry crazy ant, Nylanderia sp. nr. puben. We did this using dry artificial foods (14–42% total macronutrient content) having a range of fixed p:c ratios in a series
of choice and no-choice laboratory experiments and used worker mortality to gauge colony-level costs associated with active
nutrient regulation. Choice experiments revealed that colonies preferred carbohydrate-rich foods and self-selected a diet
having a p:c ratio ~1:2. No-choice experiments demonstrated that food p:c ratio only moderately affected worker food collection
behavior, likely because colonies regulated the intake of only the non-limiting nutrients. Absolute worker mortality was generally
high, but lowest in colonies feeding on the food having a p:c ratio of 1:2 (the p:c ratio ants self-selected in the choice
experiment), although mortality was not significantly affected by food p:c ratio. The self-selected p:c ratio in our study
is consistent with that observed in other recent ant nutrient regulation studies. Taken together, the results from these combined
studies reveal emerging commonalities among ants in macronutrient regulation strategies, and similarities in foraging behaviors
and costs associated with macronutrient regulation. Finally, from a methodological perspective, the high mortality observed
in our study, when compared with other recent studies, suggests that ant nutrient regulation studies should be conducted using
foods having high moisture and total macronutrient content. 相似文献
13.
Florian M. Steiner Bernhard Seifert Donato A. Grasso Francesco Le Moli Wolfgang Arthofer Christian Stauffer Ross H. Crozier Birgit C. Schlick-Steiner 《Organisms Diversity & Evolution》2011,11(2):107-134
The Mediterranean harvester ant species Messor minor, M. cf. wasmanni, and M. capitatus can co-occur in the same habitat. In Italian populations, we encountered colonies that contained workers from more than one
species as identified via standard morphology, as well as colonies with workers that appeared to be morphologically intermediate
between species. This unusual finding required further analysis. We analysed such colonies using microsatellites, mitochondrial
DNA and refined morphometrics, and a simple inference key for the colony-level interpretation of data from the three sources
combined. We infer that Messor minor and M. cf. wasmanni engage in bidirectional interspecific gene flow. Hybrids between these two species are inferred to produce fertile offspring,
which would indicate that barriers to hybridisation do not exist or can be completely overcome. This is unexpected, given
that they are non-sister species and broadly sympatric in nature. Our findings also indicate the possible occurrence of hybrid-hybrid
crosses, a phenomenon rarely observed in ants. We cautiously interpret the data at hand as in support of the interspecific
gene flow considerably shaping the genetic makeup of populations, raising the question about a potential adaptive value of
this hybridisation. Messor capitatus mixes with hybrids of the other two species, but we found no indication of hybridisation involving this species. We discuss
various hypotheses on the causations of colony mixing and hybridisation in the three Messor species at the proximate and ultimate level. 相似文献
14.
Y. Kamimura 《Insectes Sociaux》2008,55(1):51-53
Males of several insect species inflict wounds on female genitalia during copulation, but the significance of such copulatory
wounds for males is not clear. I compared the genitalia of virgin and mated Formica japonica females and for the first time report the occurrence of copulatory wounds in this monandrous ant species. All inseminated
females examined had two types of melanized patches, indicating wound repair, and the serrated penis valves and sharp-pointed
volsellar digitus of male genitalia were the likely instruments of these wounds. Physically damaging mating in monandrous
species supports the view that copulatory wounds do not necessarily contribute to postcopulatory fitness gains for males via
advantages in sperm competition or cryptic female choice.
Received 10 September 2007; revised 15 October 2007; accepted 16 October 2007. 相似文献
15.
D. N. Goryunov 《Entomological Review》2015,95(8):953-958
Representatives of the subgenus Coptoformica build composite aboveground nests in much the same manner as red wood ants do. However, despite the superficial similarity, Coptoformica nests show a number of substantial differences that impact on the way in which ants use the nest. The aboveground part of a Formica (Coptoformica) exsecta nest consists of the temporary layer, the outer crust layer, the mound, and the intermediate layer. The material of all the layers includes soil and fragments of plants (picked up or excised), the relative proportion of the two components differing among the layers. The thick, soil-rich crust layer acts as armature and allows a variety of anthill shapes. The intermediate layer and the upper part of the mound harbor quite a few large chambers. Building material is often transferred from nest to nest. On the whole, F. exsecta nests are plastic and movable, which facilitates the activity of these ants in ecotone biotopes. 相似文献
16.
A new species of Notocotylus was found parasiting a freshwater pulmonate snail, Biomphalaria peregrina. Naturally infected snails were collected from two temporary ponds in the Nahuel Huapí National Park in Patagonia. The characteristics of the larval stages are presented. Experimental adults were recovered from the intestinal caeca of ducks and chicks. Adults of Notocotylus biomphalariae n. sp. exhibit an aspinose tegument, two lateral rows of 11 ventral glands and a median row of four, a uterus with 12–16 coils of which 2–4 are previtelline, a metraterm equivalent in size to 65–68% of the cirrus-sac length, a previtelline field which extends to the middle of the body, a lobed testis and a genital pore closely posterior to the intestinal bifurcation. The rediae have one to three cercariae. The cercariae, when shed, are trioculate and have a long tail; they encyst in the environment and become infective 12 days after encystment. 相似文献
17.
A new species of Allassogonoporus Olivier, 1938, from a naturally infected specimen of Dromiciops gliroides, is described. Adults of A. dromiciops n. sp. were recovered from the small intestine. This new species can be distinguished from all other species of the genus
by having: the largest body and eggs, a lobed testes and ovary, a Y-shaped excretory vesicle and vitelline follicles beginning
at the level of the posterior margin of the oral sucker. This is the first record of a species of Allassogonoporus in South America and the first record of a digenean parasitising D. gliroides. 相似文献
18.
A sex-ratio bias was studied in alates of natural polygyne colonies of Solenopsis invicta Buren in southern China. The results showed that at the population level, the numbers of male and female alates were nearly
equal, even though there was a strong bias toward producing one particular sex at the nest level. For example, 88.89% of the
nests sampled were strongly biased toward males or females. In particular, three bias types were observed: extreme female
bias, extreme male bias, and a moderate bias. Future studies should address the factors that lead queens to produce strongly
biased sex ratios. 相似文献
19.
Hugh D. Wilson 《Economic botany》1990,44(3):92
Traditionally viewed as an Andean grain crop,Chenopodium quinoa Willd. includes domesticated populations that are not Andean, and Andean populations that are not domesticated. Comparative analysis of leaf morphology and allozyme frequencies have demonstrated that Andean populations, both domesticated(quinua) and free-living(ajara), represent an exceptionally homogeneous unit that is well differentiated from allied domesticates of coastal Chile(quingua) and freeliving populations of the Argentine lowlands(C. hircinum). This pattern of relationships indicates that Andean populations represent a monophyletic crop/weed system that has possibly developed through cyclic differentiation (natural vs. human selection) and introgressive hybridization. Relative levels of variation suggest that this complex originated in the southern Andes, possibly from wild types allied withC. hircinum, with subsequent dispersal north to Colombia and south to the Chilean coast. Coastal populations were apparently isolated from post-dispersal differentiation and homogenization that occurred in the Andes. Other data point toward a center of origin in the northern Andes with secondary centers of genetic diversity subsequently developing in the southern Andes and the plains of Argentina. Comparative linkage of South American taxa, all tetraploid, with North American tetraploids of the subsection will eventually clarify this problem. While the possibility of a direct phyletic connection betweenC. quinoa and the Mexican domesticate(C. berlandieri subsp. nuttalliae,) cannot be excluded, available evidence indicates that the latter represents an autonomous lineage that is associated with the basal tetraploid, C. b. subsp.berlandieri, through var.sinuatum, whereas South American taxa show possible affinities to either var. zschackei or var.berlandieri. An extinct domesticate of eastern North America,C. b. subsp.jonesianum, represents either another instance of independent domestication, possibly from subsp. b. var.zschackei, or a northeastern outlier of subsp.nuttalliae. 相似文献
20.
M. E. Cocom Pech W. de J. May-Itzá L. A. Medina Medina J. J. G. Quezada-Euán 《Insectes Sociaux》2008,55(4):428-433
Euglossa viridissima is an orchid bee that forms both solitary and multiple female nests, making it a suitable species for the study of factors
leading to diverse degrees of sociality in Euglossines. We conducted observations in eight reused nests (where a first generation
of bees had been produced) kept in artificial boxes from the Yucatan Peninsula, Mexico. Five nests were reused (reactivated)
by a single female (SFN), two nests reused by a mother and one daughter (MFN1) and one nest reused by the mother and two daughters
(MFN2). No single nest was reactivated by unrelated females. The number of foraging trips, their duration and the duration
of cell provisioning was not different between SFN and MFN. The overall production of cells per female was not different either
between both types of nest. However, in MFN although all females did lay eggs, there was a reproductive skew in favor of the
mother (95 and 45% of the brood produced in MFN1 and MFN2 respectively). She showed reproductive control of her daughters
through oophagy and displaying threatening behavior when the daughters tried to open a cell where she had laid an egg. Brood
losses to parasites (Anthrax sp. (Bom-byliidae) and Hoplostelis bivittata (Megachilidae)) were only found in SFN which possibly reflects and advantage of MFN in this respect. Our results coupled
with other studies in Euglossa, reveal that a wide range of social behaviors occur in this genus, from solitary and communal to primitive reproductive division
of labor. Multiple factors involving different levels of pressure imposed by food availability and parasites may favor such
a diverse range of nesting behaviors. Interestingly, female associations in E. viridissima seem a result of kin selection that is enforced by coercion from mother females on their daughters. More studies are needed
to shed light upon the social organization of Euglossa and other Euglossines and on their phylogenetic relationships in order to trace the origins of eusociality in Apidae.
Received 12 February 2008; revised 25 June 2008; accepted 17 July 2008. 相似文献