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1.
《Journal of Natural History》2012,46(41-42):2649-2665
Munromyia marsabitensis sp. nov. is described from the isolated mountains of Marsabit in northern Kenya. It can be distinguished from the two known congeners by the thoracic and abdominal colour patterns, structure of the male and female terminalia, and host plants. Larvae are seed predators, developing within the green, aborted fruits of Chionanthus battiscombei. Over 70% of sampled fruits (n?=?74) were infested with larvae, but nearly all of the individually infested fruits (96.1%) produced only one adult tephritid. Bactrocera biguttula, but not M. marsabitensis, was reared from ripe fruits of the same plant.  相似文献   

2.
I quantified seed production and ovule losses for Ceanothus fendleri Gray (Fendler ceanothus) plants protected from large ungulate herbivores in a ponderosa pine ( Pinus ponderosa [Laws]) forest of northern Arizona. I also tested seed germination responses to cold stratification and heat treatments in the laboratory. Fruit production on fecund stems ranged from 7.4 to 38.2 fruits per stem, which equated to 22.2-118.2 potential seeds based on 3 ovules per fruit. Stems that produced fruit were significantly large relative to their expected sizes. Predispersal ovule losses ranged from 70.7% to 91.4% across the 2 years studied. A chalcidoid seed parasite ( Eurytoma squamosa Bugbee) consumed 11%-28% of the total number of seeds produced. Postdispersal seed predation varied from 0% to 24% and was significantly affected by forest floor substrate in 1 study year. Cumulative ovule losses were estimated to be 71%-92%. Cold stratification did not significantly affect seed germination, and exposure to 90°C resulted in the highest germination percentage. Both dormant and nondormant seeds suggested a bet-hedging life history strategy. This study provides basic ecological information important for management of ponderosa pine forest and nursery production of C. fendleri .  相似文献   

3.
《Journal of Natural History》2012,46(9-10):621-635
Charoxus spinifer is associated in southern Florida with native fig trees (Ficus aurea and Ficus citrifolia). Winged adult beetles, 3.0–3.6 mm long, mate on Ficus twigs outside the syconia (fruits), and enter the syconia through holes cut by male pollinating wasps. Adults and larvae eat adult wasps within the syconia. Ovaries hold few, large, mature eggs. Larvae develop through three instars. Fully grown larvae abandon the syconia, drop to the ground, burrow to a depth of 1.5–3.7 cm, spin a silken cocoon, and pupate. Pupal duration is 8–9 days. Larval populations are highest in May, when penultimate stage syconia (phase D) are most abundant, but were detected in all months except June. Charoxus major is reported from Veracruz, associated with Ficus lapathifolia. Its adults extract wasp occupants of galled fig ovaries within syconia, and its eggs were found singly in empty galls.  相似文献   

4.
《Journal of Natural History》2012,46(29-32):1853-1861
The effects of the number of locules per fruit on seed predation in a Mediterranean woody plant (Cistus ladanifer) were analysed. Plants produced fruits with a similar number of locules (fruits with a small, intermediate or large number of locules). Nevertheless, there were no differences in the number of fruits produced or predated per plant. Different types of fruits did not differ in size, seed weight, fruit to wall ratio, insect predation rate or mean proportion of destroyed locules. They did differ, however, in the variation of the proportion of destroyed locules; fruits with few locules had a wider variation than fruits with a large number of locules. Our results suggest that phenotypic selection pressure on insect predation could give rise to more between‐fruit variation in the seed output saved from predation in those plants producing fruits with a small number of locules.  相似文献   

5.
《Journal of Natural History》2012,46(9):1743-1847
Species comprising two monophyletic groups of Alcidodes sensu lato (crassus group and dipterocarpi group) feed on fruits of the ecologically and economically important tropical timber family Dipterocarpaceae. Fifteen Alcidodes species are newly described from several thousand specimens of seed-feeding beetles reared from south-east Asian dipterocarp hosts (Dipterocarpoidae) and four other species are revised. Morphological keys are provided for identifying these 19 taxa. Weevil associations are provided for 70 species of Dipterocarpaceae in five genera (16 Dipterocarpus spp., four Dryobalanops spp., six Hopea spp., 39 Shorea spp. and five Vatica spp.). These records relate primarily to specimens reared from seeds in Borneo and in Peninsular Malaysia, but all known previous host records are also included (from India, Andaman Islands, Thailand, Laos, Vietnam and the Philippines) and assessed. These validated and documented host associations refute general assertions that (1) seed-eating beetles are host-specific in the tropics and (2) seed-eating beetles found on dipterocarp hosts are broad generalists across species in several genera of mast-fruiting Dipterocarpaceae. Most Alcidodes species exploit seeds from several dipterocarp species. Some Alcidodes species occur across broad geographic regions with several host species from a dipterocarp genus, other species have been found only on Bornean Hopea or Dipterocarpus species. Others, such as the two previously undescribed species feeding on Vatica species, may be restricted to separate sections of the host genus. Within an extensively sampled and diverse interspecific mast-fruiting dipterocarp community, no Alcidodes species was observed to feed on sympatric species across genera within the Dipterocarpaceae. Additional host records and specimens of Alcidodes spp. throughout the range of the Dipterocarpaceae in south and southeast Asia are required to further define these clades and the tribe Mecysolobini in general as well as to resolve the complex host associations and distributions documented.  相似文献   

6.
7.
Seed aggregation in latrines of rabbits is a little-studied process that may contribute substantially to seed dispersal and survival. We located Juniperus deppeana trees and the latrines used by the endemic Mexican cottontail rabbit Sylvilagus cunicularius within a 1 ha fragment of J. deppeana-dominated forest and evaluated their patterns of aggregation as microhabitats used by cottontail rabbits to consume the J. deppeana galbulus (fleshy cones) or to deposit their pellets with defecated seeds. Based on mean latrine area, we marked a 2 m × 2 m plot centred on the base of every tree or latrine within the study site. We counted all pellets within each plot and analysed them for the presence of seeds of Juniperus or any other species. We found seeds in 13% of all pellets, mainly those deposited in the latrines. If seeds are scarified by passing through the intestinal tract, seed germination in latrines may increase the probability of survival and establishment. Thus, the community structure and density could change in time as rabbits are changing the places where they place their latrines.

http://zoobank.org/urn:lsid:zoobank.org:pub:372FEED4-5DFF-4144-A384-4FB30F480A26  相似文献   


8.
《Journal of Natural History》2012,46(18):2211-2227
This study provides a detailed account of the natural history and foraging biology of the ponerine ant Dinoponera gigantea in a rainforest in north Brazil. The species nests on the ground and the colonies contain 70–96 workers. Ant activity is negatively correlated with temperature, and is more intense at dawn and dusk. Foragers leave the nest independently and search for food individually on the leaf litter, within ca 10 m around the nest. Workers are opportunistic feeders that collect seeds and fruits, and hunt for live prey as well as scavenge for dead animal matter. The dry weight of food items ranges from <10 mg (spiders, insect parts) to >400 mg (seeds, fruits). There is no nestmate recruitment during the search for or retrieval of food, irrespective of food type and size. Foragers have a high directional fidelity, and ants from neighbouring colonies may engage in ritualized territorial contests at the border of their foraging areas. The foraging ecology of D. gigantea is compared with other ponerine species living in tropical forests, as well as with other ant groups showing similar behavioural patterns.  相似文献   

9.
《Journal of Natural History》2012,46(41-42):2677-2721
ABSTRACT

Embedded within the interdisciplinary research project ‘Towards an understanding of the structure and function of a Neotropical rainforest ecosystem with special reference to its canopy’ organised by the Austrian Academy of Science, the canopy beetle fauna was surveyed by means of a 42 m tall tower crane. This paper presents results of the chrysomelid beetle fauna observed and collected at canopy trees for 1 year. A total of 1783 adult leaf beetles were collected, representing 117 morphospecies (Bruchinae are not included) including 31 singletons. The most abundant family was Galerucinae sensu stricto with 827 individuals (46% of collection). The most speciose subfamilies were Galerucinae sensu stricto followed by Alticini, Cryptocephalinae and Eumolpinae. Nineteen species collected with at least two individuals were restricted to a single tree species whereas 68 species were found to feed on several canopy host trees. Only a few species fed on leaves; these were in Cassidinae, Cryptocephalinae, Eumolpinae and Galerucinae. Strikingly, most canopy chrysomelids were collected at flowers of canopy trees, although some species fed also on extrafloral nectaries or fruits. Alticini were restricted predominantly to flowers, but Cryptocephalinae, Eumolpinae and Galerucinae revealed broader plasticity in host tissue selection. Insights into beetle seasonality, diurnal/nocturnal activity and intra-canopy migration are provided. Abundant flower-visiting species occurred on their host trees commonly over the entire flowering season, with their abundances often correlated with the number of open flowers. After termination of one tree’s flowering season, many flower-visiting leaf beetles moved to other flowering trees. Certain congeneric species of Galerucinae and Eumolpinae occurred together at their host plants within the same periods.  相似文献   

10.
Rubber rabbitbrush ( Chrysothamnus nauseosus [Pallas] Britt. ssp. viridulus ) may prove to be a source of high-quality cis-isoprene rubber, but its establishment is limited by a lack of information on seed germination. Consequently, seeds were germinated at alternating temperatures (5&ndash;15, 5&ndash;25, 15&ndash;25, and 20&ndash;30 C) in light and dark as well as constant temperatures (15&ndash;40 C with 5-C increments) to determine temperature response. Seeds were also germinated in solutions of polyethylene glycol 6000 (0 to &ndash;5 bar), salinity regimes (1, 17, 51, and 86 mM) at all the above-mentioned temperatures to determine salinity and temperature interaction. The hormones GA 3 (0, 2.9, 29.0, and 58.0 um) and kinetin (0, 4.7, 23.5, and 47.0 um) were used to study their effect on overcoming salt- and temperature-induced germination inhibition. Seeds of C. nauseosus ssp. viridulus were very sensitive to low temperature. Best germination was achieved at 25 and 30 C, but these seeds also germinated at a higher temperature (35 C). The seeds of rabbitbrush germinated at both constant and alternating temperatures. Light appears to play little or no role in controlling germination of the seeds of rubber rabbitbrush. However, seeds of rabbitbrush were sensitive to salinity, and seed germination was progressively inhibited by increase in salt concentration, although a few seeds still germinated at the highest saline level. Progressively higher concentrations of polyethylene glycol also progressively inhibited germination. Suppression of seed germination induced by high salt concentrations and high temperatures can be partially alleviated by the application of either GA 3 or kinetin.  相似文献   

11.
《Journal of Natural History》2012,46(23-24):1395-1399
ABSTRACT

Males of the green June beetle Cotinis nitida are regularly attacked by birds as they search for females on lawns but which bird species feeds on the beetle changes from year to year. In 2018 for the first time on a farm in northern Virginia, brown thrashers (Toxostomum rufum) joined blue jays (Cyanocitta cristata) as major predators of the beetles. The two species employed very different tactics when hunting for June beetles, with the thrashers searching while walking forward on the mowed lawn while the jays scanned for beetles when perched in trees about the lawn. The beetles became very scarce at the lawn in early July in 2017 and 2018 and their predators apparently moved elsewhere. Subsequently, male beetles were occasionally observed patrolling a nearby hayfield in search of mates with rare copulations recorded after July 15. Because predatory birds could not exploit the beetles in the tall grass of the hayfield it seems likely that the mowed lawn constituted an evolutionarily novel ecological trap which made searching beetles conspicuous and easily captured by beetle-hunting birds.  相似文献   

12.
《Journal of Natural History》2012,46(3-4):191-203
We describe the reproduction of Leptodactylus syphax from Brazil and attempt to trace the evolution of reproductive traits within the L. pentadactylus species group. We quantified the proportion of eggs/embryos from fresh nests. We test whether L. labyrinthicus and L. syphax tadpoles can prey on eggs from heterospecific foam nests. Egg clutches were found outside the water at the edges of rocky/seasonal streams, usually within excavated basins. Males beat the foam with their legs moving from side to side. Clutches do not have trophic eggs, since most of their eggs develop into tadpoles. Tadpoles cling on rocks in current/shallow waters. Only L. labyrinthicus tadpoles could prey on eggs from heterospecific foam nests. If the L. pentadactylus group is monophyletic, excavated basins and foam‐beating in lateral motions may be possible synapomorphies of this group. However, large adults, carnivorous tadpoles and trophic eggs appear to be associated synapomorphies of a less inclusive group.  相似文献   

13.
《Journal of Natural History》2012,46(17):1367-1380
The parasitic wasp Trogus pennator (Ichneumonidae) attacks the larvae of swallowtail butterflies (Papilionidae). Female T. pennator were followed in the field as they searched for larvae of the zebra swallowtail butterfly, Eurytides marcellus (Papilionidae), feeding on Asimina (Annonaceae) in central Florida, USA. Predictions of host‐finding theory and interactions with the host were thus investigated in a natural setting. Wasps seldom flew to plants other than Asimina and apparently recognized the plants by visual cues. Plants were attractive regardless of host presence, as the wasps approached plants lacking E. marcellus feeding damage twice as often as they approached damaged plants. However, wasps approached damaged plants at a rate greater than their frequency in the Asimina population, indicating that they can detect host damage before they approach the plants. After approaching within 0.5?m of plants, wasps tended not to land on plants lacking feeding damage. A comparison of the plants they landed on, however, showed no consistent preferences for damaged plants. The weaker trends in the latter data indicate that the presence of feeding damage was not the sole criterion for landing, although it evidently influenced behaviour. After landing, wasps spent more time searching damaged plants than undamaged plants. Butterflies preferred to oviposit on plants shorter than those searched by T. pennator. Possible adaptive consequences of this phenomenon are discussed.  相似文献   

14.
《Journal of Natural History》2012,46(35):3217-3226
Animal mating systems are moulded by ecological factors, mainly the temporal patterns of reproduction. We report the reproductive period, use of microhabitats, clutch and egg sizes, reproductive efforts, occurrence of sexual size dimorphism, and the relation between body size and fecundity in the gravid females of Trachycephalus venulosus and Scinax fuscovarius at Serra da Bodoquena, Central Brazil. The reproduction of both species was correlated with the rainy season. Females of T. venulosus produced more eggs and their eggs were larger than those of S. fuscovarius. The females of both species were larger and heavier than males. The reproductive effort was measured as the ratio of gonad mass in relation to body mass. Females of both species presented similar reproductive efforts, but males of S. fuscovarius invested more in gonads compared to males of T. venulosus. Trachycephalus venulosus presented significant correlation between snout–vent length versus number of mature eggs and body mass versus number of mature eggs and ovarian mass. Scinax fuscovarius showed significant correlation between body mass versus ovarian mass. Trachycephalus venulosus is an explosive breeder, whereas S. fuscovarius has prolonged reproduction. These species are able to adapt to several types of habitat, due to behavioural and physiological plasticity.  相似文献   

15.
《Journal of Natural History》2012,46(21-22):1313-1349
ABSTRACT

Nectaries are structures that secrete a sugary solution and can occur on vegetative and/or reproductive parts of plants. The significance of floral nectaries to reward vertebrate and arthropod pollinators is well supported. The role of extrafloral nectaries (EFNs) is more ambiguous, though research has been skewed to the ant-plant mutualism. Many other insects feed at EFNs, but these interactions are vastly understudied. This study addresses the hypothesis that EFNs may influence the occurrence and structure of Neotropical canopy beetle communities. Seven canopy trees (four families) exhibiting EFNs and their associated beetles were studied over a one-year period in southern Venezuela. In total, 6818 adult beetles identified to 868 species were recorded on 25 investigated canopy tree species (#47 individuals). Of the 868 beetle species, 150 species (517 individuals; 17.3% species) from 20 families were observed drinking from foliar EFNs on seven EFN-bearing tree species. Dietary dependence on EF nectar varied, with 95 beetle species utilising this nectar within a broader diet and 55 species found feeding exclusively on EFNs. This study demonstrates unequivocally that EF nectar is a frequently utilised food resource of many beetle adults and beetles have been a significantly underestimated visitor group. A more detailed study was conducted on six individual canopy trees of two species of Chrysobalanaceae, Licania hebantha Mart. ex Hook. f. and Moquilea subarachnophylla (Cuatrec.) Sothers and Prance. In total, 115 individual adults of 64 beetle species were collected on nectar secreted on newly-sprouted leaves. These beetle assemblages were dominated by species utilising EF nectar and were associated with distinct phenological phases of the host trees. Altogether, the beetle survey found support for the hypothesis that EFNs influence the occurrence and structure of beetle communities. These beetle-EFN relationships have implications for spatial arrangement, community assembly and evolution of both host plants and beetles. Like ant-EFN mutualism, EFN-bearing trees and beetles may also form mutualism. It is possible that the plants offer easier access to a nutritious resource that may deflect herbivory of vegetative parts.  相似文献   

16.
《Journal of Natural History》2012,46(39-40):2449-2471
Coexistence of anuran species might lead to acoustic interference among communications, especially where species are closely related. This problem might be minimized through resource partitioning. To test this idea, we analysed calling with respect to temporal and physical space usage in three syntopic, closely related species (Scinax cuspidatus, Scinax aff. hayii and Scinax aff. x-signatus) in a temporary pond in the Atlantic rainforest. The chorus attendance of each species resulted from a different combination of factors in the rainy season. Although there was some temporal overlap of daily activity among species, peak activity time differed, particularly between the two species whose calls were most similar. Although all three species tend to aggregate in open microhabitats, their coexistence is apparently facilitated by differential use of vertical strata and organization of calling sites near the sites of conspecifics. Together, these factors apparently reduce acoustic interference among heterospecific calls.  相似文献   

17.
Summary

This paper is concerned with the general biology of the notodontid moth, A. bronneomixia whose larvae are found to be serious defoliators of the West African indigo plant, Lonchocarpus cyanescens.

At temperatures fluctuating between 21°C and 29°C (mean 22·5°C) and humidities between 70 to 95 per cent eggs developed and hatched in a mean of 11·1 days from deposition, mean hatch being 93 per cent.

Under the said environmental conditions, the life cycle from egg to adult entailed six larval instars and a prepupal stage before the real pupa, all lasting 60 to 80 days. Larvae were strongly monophagous, fed communally and in nature pupated in soil/litter very close to the foot of their invaded food plant.

Adults were retiring and in the field deposited clusters of numerous eggs preferably on the abaxial surfaces of their food plants. In nature, this moth's population seemed strongly regulated by high egg and larval parasitization, larval predation and fungal attacks at the pupal stage.  相似文献   

18.
The bopyrid parasite Orbione halipori was recorded for the first time from Metapenaeus joyneri. Morphometric analysis indicated that infested male and female shrimp have slightly, but significantly, lower body weight than uninfested shrimp of the same carapace length. While the parasites sterilize their hosts, the low infestation rate (0·53%) appears not to pose a threat to the shrimp fisheries in the Zhujiang estuary.  相似文献   

19.
Summary

Eggs of G. rhomboidalis are usually laid singly in separate excavations made with the snout of the beetle in either leaf petioles or tender portions of shoots of host plants, Amaranthus sp. At field temperatures fluctuating between 19°C and 30°C and in contact with water, eggs hatched in a mean of 2·8 days while unmoistened ones shrivelled up.

Beetle larvae bore and feed on the stele of host plants where development, up to adulthood, is completed in self-made larval galleries. On the average, the larvae are capable of consuming 40% and above of the cross-sectional areas of stems of infected host plants. In nature, multiple infection of host plants was quite common with 1–16 beetle larvae/plant rather usual. Consequently, the stem of virtually every healthy-looking host plant is internally traversed by larval galleries, at times even below ground level.

Adults bite their way out of the stem after a mean of 36·37 days from date of oviposition.

Larval damages to host plants are the gravest and bring about premature breakage and/or death of crops, stunted growth and reduced yield of the wanted leaf products.  相似文献   

20.
《Journal of Natural History》2012,46(33-34):2073-2085
ABSTRACT

Allorhogas Gahan (Hymenoptera: Braconidae) is a mainly Neotropical doryctine wasp genus whose species have been associated with 11 vascular plant families. All species of Allorhogas whose feeding habits are known are confirmed or presumed to be phytophagous, either by being gall inducers on seeds, seeds predators or by inquilinism of other gall former taxa. Here we describe a new species of Allorhogas from Brazil and assess its phylogenetic affinities using one mitochondrial (COI) and one nuclear (28S) marker. Different from other described species of Allorhogas that induce galls on fruits/seeds of Melastomataceae, the new species attacks floral bud ovules of Miconia chamissois Naudin (Melastomataceae), forming ‘fruit-like’ galls. We recovered a clade exclusively composed of species of Allorhogas that attack Melastomataceae species. The new species could potentially be used as a biological control of M. chamissois populations to prevent the imbalance of the plant diversity of cerrado, which is one of the most endangered biomes in Brazil.

http://www.zoobnk.org/urn:lsid:zoobank.org:act:27ADE2CD-6C55-4712-92EC-B0F209FEFD10  相似文献   

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