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1.
Among the numerous nonparasitic allodapine bees there are 11 known species with parasitic or probably parasitic habits. These species live in nests of their close relatives, the female parasite replacing an egg-layer of the host. Seven of the parasitic species are distributed among four otherwise nonparasitic genera, while four species of parasites are placed in three exclusively parasitic genera. The parasites have mostly arisen independently from different nonparasitic forms. There is much convergence among the parasitic forms involving such characters as the flattened or concave face, reduced eyes, reduced mouthparts, reduced wing venation, and reduced pollen-carrying scopa. In the most specialized parasitic genera the mouthparts are so small as to be almost surely useless for obtaining food from flowers. Such bees must feed in the host nest, and are not found on flowers. Their wings must be adequate to take them to a new host nest but the reduced venation and eyes must reflect the reduced locomotary and sensory needs of a bee that does not visit flowers. In this paper a new, presumably parasitic Allodapula is described as is a parasitic Braunsapis, a parasitic Allodape, and a Eucondylops. A previously described Macrogalea is recognized as a parasite for the first time. A new genus and species of parasites Nasutapsis straussorum, allied to Braunsapis, is also described. All these forms are from Africa.  相似文献   

2.
Abstract The study assessed the survival, during bushfires, of seedbanks of six serotinous Hakea species found in the Sydney region of southeastern Australia. The survival of seeds was examined when fruits were heated in a muffle furnace at ambient temperatures ranging from 200–800°C for 1 min. For each species, fruit weight and dimensions of fruit walls were measured to characterize insulation. A field experiment was performed to examine the survival of the serotinous seedbank of Hakea dactyloides in a bushfire. Ambient and internal fruit temperatures were recorded during the fire. The viability of seeds from fruits exposed to the fire was tested and compared with an unburnt sample. Viability of seeds within fruits exposed in the furnace varied according to species. Seeds of large fruited species such as Hakea constablei and Hakea propinqua survived, whereas those of the small fruited species Hakea teretifolia and H. dactyloides suffered significant mortality. The threshold temperature for death in four species was linearly related to the thickness of lower and lateral fruit walls, and to dry weight of fruits. Internal and external temperatures of fruits decreased with increasing height on experimental H. dactyloides plants in the field. High levels of mortality (relative to the unburnt control) corresponded with fire temperature maxima greater than 400°C (external) and greater than 60°C (internal). In general, these temperatures occur when shrub crowns burn. A high risk of death for H. dactyloides, H. teretifolia and H. sericea seeds will result because fruits of these species have thin walls.  相似文献   

3.
Distribution of coagulation of young shoot homogenates was surveyed in 430 accessions from the orange subfamily Aurantioideae. Representatives of four genera available for study (Clausena, Glycosmis, Aegle, Feronia) were coagulating taxa. The genus Citrus included both coagulating and noncoagulating taxa. Nineteen genera (Murraya, Merillia, Pamburus, Paramignya, Triphasia, Aeglopsis, Afraegle, Balsamocitrus, Feroniella, Swinglea, Atalantia, Citropsis, Hesperethusa, Pleiospermium, Severinia, Clymenia, Eremocitrus, Poncirus, Fortunella) were noncoagulating. The status of eight genera (Micromelum, Wenzelia, Monanthocitrus, Oxanthera, Merope, Luvunga, Burkillanthus, Limnocitrus) is not known. Homogenized tissue from coagulating taxa turned into a paste while tissue from noncoagulating taxa was thin and juicy. Coagulation did not take place when the pH of the grinding medium was 11 or higher but it would occur if the pH was lowered. Homogenates of noncoagulating taxa become coagulated below pH 5.2–5.3, but remained noncoagulating above this. Noncoagulating taxa contained an unidentified substance which inhibited coagulation of tissue from coagulating taxa. The mechanism of coagulation and noncoagulaton is not presently known. The significance of coagulation and its absence as a taxonomic and genetic marker is discussed.  相似文献   

4.
Keraunea Cheek & Simão‐Bianchini gen. nov. (Convolvulaceae) from Brazil is described and illustrated as the third known neuropeltoid genus. It appears allied to the Old World genera of Neuropeltis Wall and Neuropeltopsis Ooststr. in having wind‐dispersed fruits not by enlarged sepals, but subtended by an enlarged papery bract to which the pedicel is adnate, and flowers in which the bracteoles are absent or usually very inconspicuous. Keraunea brasiliensis, the single species thus far known, is here assessed as ‘Endangered’.  相似文献   

5.
This study investigated ant seed removal of Piper sancti-felicis, an early successional Neotropical shrub. Neotropical Piper are a classic example of bat-dispersed plants, but we suggest that ants are underappreciated dispersal agents. We identified eleven ant species from the genera Aphaenogaster, Ectatomma, Paratrechina, Pheidole, Trachymyrmex, and Wasmannia recruiting to and harvesting P. sancti-felicis seeds in forest edge and secondary forest sites at La Selva, Costa Rica. We also tested for differences in ant recruitment to five states in which ants can commonly encounter seeds: unripe fruit, ripe fruit, overripe fruit, bat feces, and cleaned seeds. Overall, ants harvested more seeds from ripe and overripe fruits than other states, but this varied among species. To better understand the mechanisms behind ant preferences for ripe/overripe fruit, we also studied how alkenylphenols, secondary metabolites found in high concentrations in P. sancti-felicis fruits, affected foraging behavior in one genus of potential ant dispersers, Ectatomma. We found no effects of alkenylphenols on recruitment of Ectatomma to fruits, and thus, these compounds are unlikely to explain differences in ant recruitment among fruits of different maturity. Considering that P. sancti-felicis seeds have no apparent adaptations for ant dispersal, and few ants removed seeds that were cleaned of pulp, we hypothesize that most ants are harvesting its seeds for the nutritional rewards in the attached pulp. This study emphasizes the importance of ants as important additional dispersers of P. sancti-felicis and suggests that other non-myrmecochorous, vertebrate-dispersed plants may similarly benefit from the recruitment to fruit by ants.  相似文献   

6.
Yeasts, commonly present on the surface of fruits, are of industrial interest for the production of enzymes, flavorings, and bioactive compounds, and have many other scientific uses. The Amazonian rainforest may be a good source of new species or strains of yeasts, but their presence on Amazonian fruits is unknown. The aim of this study was to identify and characterize yeasts isolated from Amazonian native fruits using molecular and phenotypic methods. In total, 81 yeast isolates were obtained from 10 fruits species. Rep-PCR showed 29 strain profiles. Using a combination of restriction-fragment length polymorphism (RFLP) of the 5.8S-ITS region and D1/D2 sequencing of the 26S rRNA gene, 16 species were identified belonging to genera Candida, Debaryomyces, Hanseniaspora, Kodamaea, Martiniozyma, and Meyerozyma. The most dominant species were Candida tropicalis, Debaryomyces hansenii, Hanseniaspora opuntiae, and Hanseniaspora thailandica. H. opuntiae and H. thailandica showed the highest number of the strain profiles. Phenotypic profiles were variable between species, and even among strains. Screening for hydrolases showed lipolytic activity in only one isolate, while proteolytic, cellulolytic and amylolytic capabilities were not detected. Yeast presence among fruits varied, with cidra (Citrus medica) and ungurahui (Oenocarpus bataua) having the highest number of species associated. This investigation broadens the understanding and possible biotechnological uses of yeast strains obtained from Amazonian native fruits.Key words: yeast diversity, fruit, Amazonia, PCR-RFLP, 5.8S-ITS  相似文献   

7.
Xanthopygina is a group of colourful, neotropical rove beetles (Staphylinidae) comprising 28 genera and more than 350 species. While many genera are found on rotting fruits, carrion, dung and mushrooms, several taxa have evolved associations with social insects. Previous phylogenetic analyses have used only a subset of genera and were based solely on molecular data. In this paper, we performed Bayesian and maximum likelihood phylogenetic analyses of all known genera, including three potentially new genera, based on molecular (4,797 bp) and morphological (91) characters. Our results reaffirmed the monophyly of the subtribe and divided it into eight major lineages: the Elmas, Gastrisus, Isanopus, Ocyolinus, Plociopterus, Smilax, Trigonopselaphus and Xanthopygus groups. We hypothesized that myrmecophily evolved once in the common ancestor of the Smilax group, and that sphecophily possibly evolved twice, in the Trigonopselaphus and Xanthopygus groups.  相似文献   

8.
Olmeca, a new bamboo genus of two species is described from southern Mexico. It is unique among New World bamboos in its production of fruits that are large and fleshy, in contrast to the smaller, dry type—caryopsis or achene—that characterizes the other genera. The fleshy fruit is found in few other bamboos, among them Dinochloa, Melocanna, and Ochlandra. These Asiatic genera are not all closely related to each other nor to the new American genus, but do share a similar type of habitat: the tropical lowland rain forest, where ample water is available throughout the year. Besides the rare type of fruit found in Olmeca, the rhizomes of this genus develop necks up to 8 m or more long, an uncommon feature among any world bamboo of the sympodial type. The solitary culms of Olmeca grow widely spaced from one another because of these elongated, intervening necks. One species. O. recta, is known only from the mountain range of Los Tuxtlas, in Veracruz, where it grows on acidic soils derived from basalt; the other, O. reflexa, occurs on calcareous soils and has a wider range that encompasses parts of Veracruz, Oaxaca, and Chiapas.  相似文献   

9.
描述并绘制了越南唇形科一新属及新种:日轮果属(Heliacria Bo Li,C.L.Xiang,T.S.Hoang&Nuraliev)和日轮果(H. maritima Bo Li,C.L.Xiang,T.S.Hoang&Nuraliev)。日轮果属因具攀援藤本习性,花大且花冠为纯白色,花萼近辐射对称、5深裂、裂片长且在果期增大并开展,果实顶端具放射状的瘤状突起等特征而明显区别于黄芩亚科的其他5属。目前,该属仅发现于越南东南部沿海的平定省、富安省、庆和省和宁顺省,常生于海岸边干旱的低地矮林中。  相似文献   

10.
A taxonomic review of Korean Haliplidae Aubé is presented. Eight species in two genera are recognized, one of which (Haliplus diruptus Balfour‐Browne) is reported for the first time in South Korea. We also found that H. ovalis Sharp previously recorded in the Korean peninsula was an incorrect identification of H. chinensis Falkenström. Habitus and scanning electron microscopy (SEM) photographs, diagnoses of genera, additional characters of species and diagnostic characters with illustrations of the species are provided.  相似文献   

11.
The species composition and quantitative characteristics of the phytoplankton in Minonosok Bight were studied in the spring and fall of 1997 and 1999. One hundred thirty-three algal species and intraspecies taxa were identified. The cell density of the phytoplankton varied from 0.03 to 19.6 million cells/l, and its biomass ranged from 0.02 to 19 g/m3. Both the density and biomass were at a maximum in June and August. Nine potentially toxic species were found, among which the genera Pseudo-nitzschia H. Pera., Alexandrium Halim, and Dinophysis Ehr. predominated. The density of these genera exceeded the reportedly harmul level during the whole summer.  相似文献   

12.
Patterns of gonad structure in hermaphroditic gobies (Teleostei Gobiidae)   总被引:5,自引:0,他引:5  
Synopsis Hermaphroditism has been reported for a small number of gobiid fishes, but the extent of this sexual pattern within the family is not known. Gonad structure was examined in one or more species from twenty-one gobiid genera. No evidence of hermaphroditism was found in the species selected from 14 genera. Laboratory studies supported the conclusion of gonochorism for the examined species in four of them:Asterropteryx, Bathygobius, Gnatholepis, andPsilogobius. Currently, the absence of precursive testicular tissues associated with the ovary in females, in conjunction with no retained ovarian features in the testes of males, appear to be reliable indicators of a gonochoristic sexual pattern in gobiid fishes. Evidence for hermaphroditism was observed in seven genera:Eviota, Trimma, Fusigobius, Lophogobius, Priolepis, Gobiodon, andParagobiodon. Protogyny was experimentally confirmed inE. epiphanes, and the gonad structure in another nine of ten species ofEviota suggested either protogyny or protogynous tendencies. With the exception ofGobiodon andParagobiodon, which exhibited similar gonadal structure, ovarian and testicular structure varied considerably among the hermaphroditic genera examined, both with regard to the configuration and to the degree of development of ovarian and testicular tissues, or testicular tissue precursors. Findings of this study indicate that hermaphroditic gonad structure will prove to be a useful trait in determining evolutionary relationships within the Gobiidae.  相似文献   

13.
A new genus and species Gordoniopsis polysperma and two new species of Gordonia (Gordonieae, Camellioideae, Theaceae) are described based on fossil fruit and seed remains. These specimens are part of a large flora consisting of various plant organs from the middle Eocene Claiborne Formation in western Kentucky and Tennessee. Gordoniopsis is a five-valved loculicidally dehiscent capsule similar to capsules of Gordonia but differing in having unwinged seeds and a greater number of seeds per locule. The two Gordonia species are among the earliest unequivocal records of the genus and two of only four fossil Gordonia species known with in situ seeds. Two extinct genera, Gordoniopsis and Andrewsiocarpon, and the extant genus Gordonia in the tribe Gordonieae are known from the middle Eocene Claiborne flora, suggesting an early radiation within the tribe. Based on a survey of Recent fruits and seeds we concur with Keng's proposal to merge Laplacea with Gordonia.  相似文献   

14.
Fin-winged fruits have two or more wings aligned with the longitudinal axis like the feathers of an arrow, as exemplified by Combretum, Halesia, and Ptelea. Such fruits vary in dispersal mode from those in which the fruit itself is the ultimate disseminule, to schizocarps dispersing two or more mericarps, to capsules releasing multiple seeds. At least 45 families and more than 140 genera are known to possess fin-winged fruits. We present an inventory of these taxa and describe their morphological characters as an aid for the identification and phylogenetic assessment of fossil and extant genera. Such fruits are most prevalent among Eudicots, but occur occasionally in Magnoliids (Hernandiaceae: Illigera) and Monocots (Burmannia, Dioscorea, Herreria). Although convergent in general form, fin-winged fruits of different genera can be distinguished by details of the wing number, texture, shape and venation, along with characters of persistent floral parts and dehiscence mode. Families having genera with fin-winged fruits and epigynous perianth include Aizoaceae, Apiaceae, Araliaceae, Asteraceae, Begoniaceae, Burmanniaceae, Combretaceae, Cucurbitaceae, Dioscoreaceae, Haloragaceae, Lecythidiaceae, Lophopyxidaceae, Loranthaceae, and Styracaceae. Families with genera having fin-winged fruits and hypogynous perianth include Achariaceae, Brassicaceae, Burseraceae, Celastraceae, Cunoniaceae, Cyrillaceae, Fabaceae, Malvaceae, Melianthaceae, Nyctaginaceae, Pedaliaceae, Polygalaceae, Phyllanthaceae, Polygonaceae, Rhamnaceae, Salicaceae sl, Sapindaceae, Simaroubaceae, Trigoniaceae, and Zygophyllaceae. This survey has facilitated the identification of fossil winged fruits such as Combretaceae and Araliaceae in the late Cretaceous of western North America and provides additional evidence toward the identification of various Cenozoic fossils including Brassicaceae, Fabaceae, Polygonaceae, Rutaceae, and Sapindaceae.  相似文献   

15.
The fagaceous genus Trigonobalanus as recently treated includes 3 species, two in Malaysia and Southeast Asia and a single species in Colombia, South America. Character analysis suggests that the genus as currently circumscribed is paraphyletic, without synapomorphies to unite the three species. Each of the three species is a morphologically distinct relict of a group that probably was ancestral to the modern genera Quercus and Fagus. Each of the three species also has at least one autapomorphy which is unique within Fagaceae. Analysis of cupule morphology in Fagaceae provides an interpretation of evolution in cupules which differs substantially from Forman's interpretation. We interpret trigonobalanoid cupules as indicative of an ancestral type of inflorescence within Fagaceae. This inflorescence type is a dichasial structure in which the outermost axes are cupular valves, but the degree of branching and subsequent number of fruits are variable. Following this model, a strict relationship exists between valve number and fruit number as seen in cupules of Trigonobalanus (valves = fruits + 1). Fossil evidence is consistent with our interpretation of the phylogenetic position of the trigonobalanoids. We propose to segregate the three species of Trigonobalanus as three monotypic genera; two of these require names which we provide here: Formanodendron and Colombobalanus.  相似文献   

16.
Bees are known to collect pollen and nectar to provide their larvae and themselves with food. That bees, especially the tropical stingless bees (Apidae: Meliponini), also collect plant resins has, however, been barely addressed in scientific studies on resource use in bees. Resins are used for nest construction, nest maintenance and nest defence. Furthermore, some South‐East Asian species transfer resin‐derived terpenes to their cuticular profiles. The resin requirement of bees is in turn used by certain plant species, which attract bees either for pollination by providing resin in their inflorescences, or for seed dispersal by providing resin in their seed capsules (mellitochory). Mellitochory is found in the eucalypt tree Corymbia torelliana, the resin of which is collected by Australian stingless bees. We investigated how the interaction between C. torelliana and resin‐collecting bees affects the chemical ecology of two Australian stingless bee genera by comparing the chemical profiles of eight bee species with resin from C. torelliana fruits. The two bee genera differed significantly in their chemical profiles. Similar to South‐East Asian stingless bees, 51% of all compounds on the body surfaces of the five Tetragonula species were most likely derived from plant resins. Up to 32 compounds were identical with compounds from C. torelliana resin, suggesting that Tetragonula species include C. torelliana compounds in their chemical profiles. By contrast, few or none resinous compounds were found on the body surfaces of the three Austroplebeia species sampled. However, one prominent but as yet unknown substance was found in both C. torelliana resin and the chemical profiles of all Tetragonula and four Austroplebeia colonies sampled, suggesting that most colonies (76%) gathered resin from C. torelliana. Hence, C. torelliana resin may be commonly collected by Australian stingless bees and, along with resins from other plant species, shape their chemical ecology.  相似文献   

17.
Twenty-three species of benthic hydroids, belonging to eight families and 13 genera, were found in a hydroid collection from Peter I Island, collected during both the Bentart 2003 and Bentart 2006 Spanish expeditions with BIO Hespérides in 2003 and 2006. Fourteen out of the 23 species constitute new records for Peter I Island, raising the total number of known species in the area to 30, as also do seven out of the 13 genera. The majority of the species are members of the subclass Leptothecata; the subclass Anthoathecata being scarcely represented. Sertulariidae is the family with the greatest number of species in the collection, with eight species (35%), followed by Lafoeidae with five (22%). Symplectoscyphus with four species (17%) and both Antarctoscyphus and Halecium with three (13%), including H. frigidum sp. nov., were the most diverse genera. Twenty species (ca. 77%) are endemic to Antarctic waters, either with a circum-Antarctic (11 species, ca. 42%) or West Antarctic (9 species, ca. 35%) distribution. Twenty-four (ca. 92%) are restricted to Antarctic or Antarctic/sub-Antarctic waters; only two species have a wider distribution. Peter I Island hydroid fauna is composed of typical representatives of the Antarctic benthic hydroid fauna, though it is characterized by the low representation of some of the most diverse and widespread Antarctic genera (Schizotricha and Staurotheca).  相似文献   

18.
Trees in pastures attract seed dispersers, leading to increased seed arrival under their canopies and more rapid regrowth around them. The characteristics that make some trees better `recruitment foci' than others, however, are poorly understood. In a neotropical pasture, we examined the arrival of seeds to open areas and underneath four genera of trees that varied in canopy architecture and type of fruit produced: Ficus trees had dense canopies and fleshy fruits, Pentaclethra trees had dense canopies and dry fruits, Cecropia trees had sparse canopies and fleshy fruits, and Cordia trees had sparse canopies and dry fruits. We found that all trees received more seeds than open pasture, probably because trees provided seed dispersers with better perches, protection from predators, nesting sites, etc. Among the tree genera, more seeds arrived under trees that produced fleshy fruits than trees that did not. This occured even during periods when trees were not fruiting (i.e., non-fruiting Ficus and Cecropia trees received more seeds than Cordia or Pentaclethra trees). Seed dispersers may periodically check Ficus and Cecropia trees for fruits, or they may become familiar with these trees while feeding and thereafter use them for other reasons. Height of trees had a slight positive effect on seed arrival, possibly because taller trees offered more protection from predators. Canopy architecture and distance to forest edge did not significantly affect seed arrival. This study demonstrates that trees in general are potentially important recruitment foci, but that different types of trees vary in the kind of recruitment that they foster in pastures.  相似文献   

19.
Tephritidae fruit fly larvae develop entirely in the host chosen by the females. To improve the fitness of their progeny, females would benefit from rejecting previously exploited hosts. Anastrepha fraterculus and Ceratitis capitata are two species of fruit flies having similar nutritional requirements and overlapping in their distribution. Previous studies found that competition between the larvae of these species might reach high levels, suggesting that cross-recognition would be an adaptive trait. In this work, we tested the ability of A. fraterculus and C. capitata females to recognize and avoid fruits previously infested by both conspecific and heterospecific females. In laboratory behavioural arenas, females were presented with fruits that had been previously exposed to either conspecific or heterospecific females. Then, we conducted choice and non-choice assays to compare the response of A. fraterculus and C. capitata females to infested and non-infested fruits. In non-choice tests, the females from both species rejected fruits previously infested by conspecific and heterospecific individuals. However, the rejection occurred at different steps of the sequence leading to oviposition: A. fraterculus showed a lower rate of visits to infested fruits, whereas C. capitata visited both infested and non-infested fruits, but the latency to visit a fruit and the rejection frequency were higher and the duration of the visit to infested fruit was lower. In choice assays, the rejection of heterospecific infested fruit was higher than that of conspecific infested fruits, for both species. Our results suggest that, regardless of the sensory mechanism used by females, the recognition of previous infestation is bidirectional and females of both species, belonging to different genera, recognize fruit infested by heterospecifics. These responses indicate that cross-recognition, supposedly a highly beneficial trait, could be occurring in nature, thus reducing interspecific competition and contributing to the coexistence of these species.  相似文献   

20.
Beaman , J. H. (Michigan State U., East Lansing), D. C. D. De Jong , and W. P. Stoutamire . Chromosome studies in the alpine and subalpine floras of Mexico and Guatemala. Amer. Jour. Bot. 49(1): 41–50. Illus. 1962.—Chromosome counts of 101 collections representing 69 species in 42 genera and 22 families have been obtained. Counts are reported for the first time in 59 species and 2 genera (Oreobroma and Villadia). Counts establishing new basic numbers were found in Draba, Lithospermum, and possibly in Arenaria. Where pertinent, the chromosomal data are related to previous taxonomic or chromosomal investigations. Chromosome numbers are now known in nearly half of the species in the alpine flora of Mexico.  相似文献   

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