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1.
The floral biology ofTetrastylis ovalis and its pollination by bats was studied in southeastern Brazil. The flowers ofT. ovalis seem more fitted to bat-pollination than those ofPassiflora mucronata, the other known chiropterophilous passionflower. Two species of bats were observed visiting flowers ofT. ovalis: the phyllostomidsGlossophaga soricina andRhinophylla pumilio. Due to the attributes ofTetrastylis, its presumed primitiveness and a better defined bat-pollination syndrome we suggest that chiropterophily evolved independently in the former genus and inPassiflora.  相似文献   

2.
Abstract— A cladistic analysis of the South American grasshopper genera Scotussa and Leiotettix was performed in order to test the monophyly of these genera. Eurotettix, Chlorus and the Dichroplus bergi species group were included as terminal taxa. The genus Atrachelacris was used to root the tree. Twenty-nine characters from external morphology, male genitalia and female ovipositor were used in the analysis. In order to test for association between the structural change that occurred in the ovipositor valves of Scotussa and the functional change of the oviposition habits, the data matrix was partitioned and two analyses were performed. Characters from the female ovipositor were excluded from the data set used in the first analysis and another analysis was performed where all the characters were included in the analysis. Information on oviposition habits was then mapped on the cladogram, to determine the transformation for performance. Both analyses yielded only one most parsimonious tree and produced congruent results, confirming the monophyly of Leiotettix and Scotussa and corroborating their close relationship. Characters from the female ovipositor valves were informative not only at the species level but also at higher levels in the cladogram. The results also support the hypothesis of association between the structural change that occurred in the ovipositor valves of Scotussa with the functional change in the oviposition habits. However, this association did not seem to be correlated with the adaptive radiation in the genus.  相似文献   

3.
The 128 known native Hawaiian species of the tribe Platynini are analysed cladistically. Cladistic analysis is based on 206 unit-coded morphological characters, and also includes forty-one outgroup taxa from around the Pacific Rim. Strict consensus of the multiple equally parsimonious cladograms supports the monophyly of the entire species swarm. The closest outgroup appears to be the south-east Asian-Pacific genus Lorostema Motschulsky, whose species are distributed from India and Sri Lanka to Tahiti, supporting derivation of the Hawaiian platynines from a source in the western or south-western Pacific. The biogeographic relationships of the Hawaiian taxa are analysed using tree mapping, wherein items of error are minimized. The area cladogram found to be most congruent with the phylogenetic relationships, and most defensible based on underlying character data is {Kauai[Oahu(Hawaii{Lanai[East Maui(West Maui + Molokai)]})]}. This progressive vicariant pattern incorporates progressive colonization from Kauai, and vicariance of the former Maui Nui into the present islands of Molokai, Lanai, West Maui and East Maui. The evolution of flightlessness, tarsal structure, pronotal setation and bursal asymmetry are evaluated in the context of the cladogram. Brachyptery is a derived condition for which reversal is not mandated by the cladogram, although repeated evolution of reduced flight wings is required. Tarsal structure supports Sharp's (1903) recognition of Division 1 as a monophyletic assemblage, but exposes his Division 2 as a paraphyletic group requiring removal of the genus Colpocaccus Sharp. Pronotal setation is exceedingly homoplastic, and is not useful for delimiting natural groups. Left-right asymmetry of the bursa copulatrix reversed twice independently, resulting in mirror-image bursal configurations in B. rupicola and Prodisenochus terebratus of East Maui. The amount of character divergence is greater among species comprising Division 1 than among species of its sister group, the redefined Division 2. Based on superior fit of Division 1 relationships to the general biogeographic pattern, a greater speciation rate coupled with more extensive extinction is rejected as the cause for this greater divergence. Intrinsic differentiation in the processes underlying cuticular evolution appears to be more consistent with the observed biogeographic and morphological patterns.  相似文献   

4.
For Madagascan vicariance biogeography and phylogeny‐based conservation, four land snail groups have been predicted as most readily informative: Acavidae, Boucardicus (Cyclophoridae), Reticulapex (Charopidae), and Streptaxidae. Acavids have been evaluated in a previous paper; this paper uses recently described taxa from three mountains in southeastern Madagascar to evaluate the other three groups, based on shell and reproductive characters. Phylogenetic analyses, using appropriate outgroups, were performed on all 17 Boucardicus (31 characters, 120 states), all nine Reticulapex (21 characters, 53 states), and all 15 streptaxids (19 characters, 68 states) known from the three mountains. The Boucardicus cladogram was marginally robust; it supported monophyly of the genus, and it implied evolutionary trends toward larger, more colour‐patterned, more globose shells hatched from larger eggs; toward a dorsally and more weakly papillate penis with a large, external gland; and toward a broad‐based, tightly convoluted fertilization pouch‐seminal receptacle complex with an internal, muscular funnel. A convergence in high‐spired shells supported the recent synonymization of Madecataulus under Boucardicus. According to the cladogram, a three‐lobed apertural peristome was plesiomorphic, was lost, then reappeared convergently. Among the 12 dissected species of Boucardicus, morphology of the female reproductive system was extremely variable (11 of 14 character states autapomorphic). The Reticulapex cladogram supported monophyly of the genus but gave no robust resolution among species. Recent surveys also indicate that Reticulapex is rare to absent in northern Madagascar. The streptaxid cladogram suggested a sister‐group relationship between the endemic clades Par‐vedentulina and Streptostele (Makroconche), but provided no robust resolution among species within either clade or within Gulella. Anatomical material is relatively scarce for Madagascan streptaxids. Vicariance‐biogeographic analysis resulted in the area cladogram (northern Vohimena mountain chain (southern Vohimena chain (southern Anosy chain))). The Vohimena chain, already known for its significantly greater diversity and endemism than the Anosy chain, thus also séems to harbour the older, more plesiomorphic species; this heightens the urgency for conservation and further survey within the Vohimena chain. Acavids (115 species known) remain the most accessible of Madagascar's major, widespread land‐snail groups for island‐wide phylogenetics and biogeography, mainly because of existing frozen‐tissue collections, which have a limited shelf life. Boucardicus (177 species and 6 subspecies known) is clearly the second most accessible.  相似文献   

5.
BACKGROUND AND AIMS: Of the set of syndromes displayed by specialized (euphilic) flowers, adaptation to pollination by bats (chiropterophily) is the least known. Accumulated new evidence reveals that this pollination mode plays a considerable role in tropical communities, especially in the neotropics. One family in which bat-pollinated species are known in several genera is the Bignoniaceae. Here is reported, for the first time, bat pollination and floral ecology in Adenocalymna dichilum (tribe Bignonieae). METHODS: Floral features of this species growing in Bahia (north-east Brazil) indicated possible chiropterophily, which was subsequently confirmed by direct observation and from photographs of bat visits. Timing of anthesis and nectar parameters were monitored in the field, and floral morphology was investigated with fixed flowers. KEY RESULTS: One to two flowers open per night on the upright, simple racemes of A. dichilum during several weeks in a 'steady state' mode. The bilabiate, cream-coloured corollas are functional for only a single night and wilt during the following day. A stout corolla, with a musky odour, and a large nectary disc with large quantities of watery nectar also conform to the syndrome. Glossophaga soricina (Glossophaginae) visited and pollinated the flowers in a trap-lining manner. Whilst hovering, the bats put their heads into the corolla mouth for less than 1 s to feed, thereby effecting the transfer of pollen which is deposited on their backs. CONCLUSIONS: Adenocalymna, a New World genus comprising approx. 50 species, exhibits floral adaptive radiation including species pollinated by bees, birds and possibly moths. The discovery of chiropterophily in A. dichilum adds another facet to the array of floral syndromes represented in the genus.  相似文献   

6.
Abstract. The Australian genus Solonaima comprises thirteen described plus two undescribed species. Six are cavernicolous, obligate or not, and are found in different caves. The phylogeny presented here confirms the monophyly of the genus. This phylogeny was compared with the estimate obtained using the method of Marques and Gnaspini, who recommend coding characters susceptible to parallelism differently from the others. Further comparison was made with a cladogram derived from the matrix from which such characters susceptible to parallelism were withdrawn. Scenarios concerning historical invasions of caves were tested using phylogenetic inference. The most-parsimonious hypothesis proposed four invasions of the caves, within two of which a diversification of species took place.  相似文献   

7.
Lopezia, a genus of 22 species largely restricted to Mexico, forms a monophyletic group defined by the possession of two stamens in tetramerous flowerS. A cladistic analysis of the genus was performed using 16 characters from morphology, anatomy and embryology. Twenty of the 22 species were considered the terminal taxa. Polarity of the characters was based on the outgroup comparison method, using three alternative outgroups: the genus Fuchsia, Onagraceae excluding Ludwigia, and Epilobieae-Onagreae. Using Fuchsia as outgroup, 29 equally parsimonious cladograms were produced, each with 24 steps and a consistency index of 0.75. A successive weighting procedure was applied, resulting in 15 cladograms with consistency index of 0.85. The strict consensus cladogram defines eight monophyletic groups and supports most of the current sectional classification of Lopezia, with the exception that no synapomorphy defines section Jehlia. The larger sections Lopezia and Pelozia, although well-defined as clades, are not fully resolved internally. All cladograms support section Riesenbachia as monophyletic. The two alternative hypotheses for outgroups produced similar results: 61 most parsimonious trees, reduced after the successive weighting procedure to 15, which are identical to those produced with Fuchsia as outgroup. These results are discussed in the context of data on cytology and pollination biology.  相似文献   

8.
Cladistic analyses of the animal kingdom   总被引:11,自引:0,他引:11  
A recently published book on the phylogeny of the animal kingdom, written by the first author, provided a classification based on a 'manual' cladistic analysis at the phylum level. We have extracted a data matrix consisting of 61 characters for 32 phyla from this book and treated it in more formal analyses using three different parsimony programs. Following a posteriori weighting, one cladogram emerged as the most parsimonious explanation of the data. This cladogram is compared to those in recent publications. Congruence is greatest with the phylogeny published by the first author, as the monophyly of 18 of the 21 supraphyletic categories proposed therein are supported in our cladogram. The exceptions are Aschelminthes, Frotornaeozoa and Neorenalia, but the latter group does emerge as a monophyletic taxon in a number of equally parsimonious, equally weighted trees. Comparisons with other recent phytogenies show varying degrees of divergence, especially concerning the monophyly of Spiralia and Aiticulata, both of which are advocated in the present paper. Significant characters of most of the supraphyletic taxa proposed by the first author are discussed. C1996 The Linnean Society of London  相似文献   

9.
Abstract.
  • 1 Honey bees foraging for nectar on lavender (Lavandula stoechas) chose inflorescences with more of their flowers open. The number of open flowers predicted whether an inflorescence was visited by bees, inspected but rejected, or ignored. Inflorescences chosen arbitrarily by observers had numbers of open flowers intermediate between those of visited and ignored inflorescences.
  • 2 Differences in morphological characters between types of inflorescence correlated with nectar volume and sugar weight per flower so that visited inflorescences had a disproportionately greater volume of nectar and weight of sugar per flower and greater variance in nectar volume.
  • 3 Although there were significant associations between nectar content and the morphological characters of inflorescences, discriminant function analysis revealed discrimination on the basis of morphology rather than nectar content.
  • 4 Visited inflorescences tended to have smaller than average flowers but bees tended to probe the largest flowers on visited inflorescences.
  • 5 Choice of flowers within inflorescences is explicable in terms of the relationship between flower size and nectar content.
  相似文献   

10.
Summary The genus Capparis is represented in Israel by three taxons of the section spinosa. The pollinators of the three taxa are hawkmoths, crepuscular bees of the genus Proxylocopa and various daily bees. However, the efficiency of the different pollinators is very varied with respect to the individual taxons. Hawkmoths were frequently observed as pollinators of C. spinosa var. aravensis and C. ovata, but rarely on C. spinosa var. aegyptia. All the other bees, on the other hand, were found abundantly on all three taxons, all over the country. The three taxa all provide different rewards for their particular pollinators. Bees visiting C. spinosa var. aegyptia are provided with a lot of pollen but a relatively small amount of nectar, with a low sugar content. C. spinosa var. aravensis and C. ovata (the flowers visited more by hawkmoths), have less pollen but a higher amount of nectar which has a higher concentration of sugar. In drier habitats the emphasis of the reward provided by the flowers is nectar, whilst in the Mediterranean habitats it is the pollen which is the reward, without any connection to the systematic origin of the plant.  相似文献   

11.
本文概述了当前分支系统学研究中涉及的主要理论和方法,包括性状的选取、性状状态和极性的确定、数据矩阵的分析计算、结果分支图的处理、分支图可靠性的评价及分支图的应用。本文同时以华东地区樟科山胡椒属Linderal2个种的分支系统学研究为例,讨论了用形态性状进行分支系统学研究中可能遇到的问题,也揭示了一些分支系统学与传统的系统学在应用性状推导进化关系上的不同点。对这12个种的分支系统学研究得出了一些不同于传统系统学方法所推测的山胡椒属内的系统发育关系,如分支系统学研究显示山胡椒组和球果组很近缘。在严格一致性分支图上,杯托组的黑壳楠和江浙山胡椒分别位于最原始和最进化的分支,表明这个组是复系类群。分支图也显示山胡椒组可能是复系类群。  相似文献   

12.
Patterns of plant visitation by nectar-feeding lizards   总被引:1,自引:0,他引:1  
Douglas A. Eifler 《Oecologia》1995,101(2):228-233
Geckos in the genus Hoplodactylus visit flowers to feed on nectar. I examined the patterns of flower visitation exhibited by two gecko species (H. maculatus and H. duvauceli) having access to two plant species: pohutukawa (Metrosideros excelsa: Myrtaceae) and flax (Phormium tenax: Agavaceae). Individual geckos were not observed to visit both plant species; individuals visiting flax tended to revisit the same plant. Geckos visiting pohutukawa were larger than those visiting flax and exhibited an early night peak in plant visitation, while lizards on flax displayed a more even pattern of activity throughout the night. On flax, geckos were more likely to be found on plants with a greater number of male flowers. Male flax flowers were of greater diameter than female flowers and produced nectar at higher rates and with greater concentrations of sugars. Experimental manipulation of pohutukawa nectar volumes suggested that the distribution of geckos is influenced by the pattern of nectar availability.  相似文献   

13.
The phylogeny of the genus Rivellia Robineau‐Desvoidy was inferred from mitochondrial 16S ribosomal (r)DNA gene sequences of 13 Korean Rivellia species and six species representing other platystomatid genera and the family Tephritidae. We compared the inferred molecular phylogeny with the previously published morphological cladogram. As a result, the following phylogenetic relationships were recognized: (i) monophyly of the genus Rivellia; (ii) monophyly of the R. syngenesiae species group; (iii) R. depicta and R. apicalis (which were not previously placed in any species group) were recognized as a sister group of the R. syngenesiae species group; and (iv) monophyly of the R. basilaris species group was recognized to a limited extent. These results, even though geographically limited, provide a new insight into the phylogeny of the genus Rivellia. They clearly show the utility of 16S rDNA for phylogenetic analysis of the genus Rivellia. Additional study involving samples from different geographical areas will be needed to gain a better understanding of the adaptive radiation of this species‐rich genus.  相似文献   

14.
木兰科的分支分析   总被引:10,自引:1,他引:10  
主要以形态学、解剖学、细胞学为依据,以德坚木属为外类群,用分支分析的方法探讨了木兰科属间的系统发育关系。有23个分支单位,选取32个性状,根据外类群比较原则和化石地层学资料,确定了性状的祖征和衍征。对数据矩阵的分支分析使用PAUP3.1.1和Hennig 86 v.1.5分别在Macintosh和IBM机上运行,前者以启发法,后者以BB命令运算,经严格一致化处理,得到一致化分支图。结果表明:1)木  相似文献   

15.
Many species of animal-pollinated flowers are known to vary widely in the nectar content of flowers. Some proportion of flowers in many species is apparently nectarless, and such flowers are believed to be ‘cheaters’. Cheating may explain a part of the variability in nectar content. If cheating exists as a qualitatively different strategy then we expect bimodality in the distribution of nectar content of flowers. It has been shown in a multispecies study that gregarious species have a higher proportion of cheater flowers. We studied the frequency distribution of total nectar sugar in two gregariously flowering species Lantana camara and Utricularia purpurascens, which differed in other floral and ecological characters. At the population level, both the species showed significant bimodality in the total sugar content of flowers. The obvious sources of heterogeneity in the data did not explain bimodality. In Lantana camara, bimodality was observed within flowers of some of the individual plants sampled. In Utricularia purpurascens the proportion of nectarless flowers was more in high-density patches, suggesting that the gregariousness hypothesis may work within a species as well. The results support the hypothesis of cheating as a distinct strategy since two distinct types of flowers were observed in both the species. The effect of density in Utricularia purpurascens also supports the gregariousness hypothesis.  相似文献   

16.
A cladistic analysis was conducted to test the monophyly of Eschweilera and Lecythis as well as to examine the relationships of these two genera and their close relatives Bertholletia and Corythophora. The study included 86 species, representing all four genera and covering the range of taxonomic and morphological variation in the genera. The data matrix included 49 parsimony-informative characters derived from vegetative, floral, fruit, and seed morphology and anatomy. The results based on the consensus of all most parsimonious trees indicate that Bertholletia, Corythophora, Eschweilera, and Lecythis form a clade supported by brachyparacytic stomata, the absence of pedicels (with subsequent reversals in several clades), a two or four-locular ovary, the presence of an aril, and the absence of cotyledons. Within the clade, the monophyly of Corythophora is supported by the presence of inflorescence scales and the absence of nectar. Eschweilera is monophyletic only if E. congestiflora and E. simiorum are excluded. The monophyly of Eschweilera is supported by the presence of a two-locular ovary. Lecythis is not monophyletic, but sections Corrugata, Pisonis, and Poiteaui are monophyletic. Three species of section Lecythis are more closely related to Eschweilera, and other species of section Lecythis along with Bertholletia excelsa remain as unresolved.  相似文献   

17.
葛属(Pueraria DC.)的分支分析   总被引:6,自引:0,他引:6  
本文采用24个形态状对葛属进行分支分析,得到了11个最简约分支图和一个严格一致化分支图,葛属的种间关系,根据分支分析结果对van der Maesen的葛属分类系统提出了修订意见。  相似文献   

18.
Great karyotypic diversity exists within the platyrrhine genus Aotus. Primarily by comparing banded karyograms of different forms of Aotus, the pattern of karyotypic evolution can be assessed. Out-group comparisons are used to establish primitive and derived states of particular chromosomes, and a parsimonious cladogram is constructed. Other karyotypic changes are then positioned at appropriate nodes of the cladogram. The resulting phylogenetic hypothesis is entirely self-consistent, is in accord with out-group comparisons, does not invoke hybridization between ancestral forms, and, importantly, indicates a single origin for each rearrangement of euchromatic segments. Moreover, it is consistent with the hypothesis, derived from pelage studies, that the more southerly Aotus taxa constitute a holophyletic group. The reconstructed ancestral karyotype had a diploid number of 54. There has been little loss of euchromatic material during Aotus evolution.  相似文献   

19.
The genus Enkianthus (Ericaceae) has been subject to a cladistic analysis of morphological, anatomical, embryological, and cytological data, using two species of Clethra as outgroup. In order to evaluate the monophyly of Enkianthus , the genera Epigaea and Phyllodoce from the subfamily Rhododendroideae, and the genus Andromeda from the subfamily Vaccinioideae were also included in an initial analysis which yielded 20 equally parsimonious cladograms. The results indicated that Enkianthus is monophyletic, and a subsequent analysis with only the outgroup taxa and 14 species of Enkianthus yielded two equally parsimonious cladograms with a more resolved topology. In order to obtain strictly monophyletic taxa, the current subgeneric classification of Enkianthus is revised, recognizing four sections: Enkianthus (9 spp.), Andromedina (2 spp.), Meisteria (2 spp.), and Enkiantella (4 spp.). The paper provides a key, illustrations of representative taxa, a cladogram, and strict consensus trees.  相似文献   

20.
The endoskeletal girdles, anocleithrum and paired fin supports of the porolepiform fish Glyptolepis (Osteichthyes: Sarcopterygii: Porolepiformes) are figured and described. The pectoral fin skeleton is known from the proximal part only and the pelvic fin skeleton is fragmentary, but the scapulocoracoid, anocleithrum and pelvic girdle can be reconstructed in their entirety. The anocleithrum is entirely subdermal. The pectoral fin skeleton in shown to be biserial, with a large number of axial mesomeres, whereas the pelvic fin contains fewer mesomeres and is strongly asymmetrical with very few postaxial radials. The scapulocoracoid is essentially similar to a reconstruction figured by Jarvik (1980), but has a more elongate glenoid; this has functional implications. The pelvic girdle consists of two separate halves as in Eusthenopteron, but differs from that genus in lacking dorsolateral rami. A brief survey of the evidence of paired fin structure in other porolepiform genera is carried out to establish whether the structures seen in Glyptolepis are likely to be representative for the Porolepiformes. A study of the morphology and muscle attachments of the paired fin skeletons indicates that the pattern of fin movement was significantly different from that in Neoceratodus. The fin supports and girdles of Glyptolepis are compared with those of other sarcopterygian groups as well as with actinopterygians, placoderms and sharks, in order to establish evolutionary polarities. Glyptolepis is shown to display a number of derived characters. The information gained from the comparison is used to construct a maximum parsimony cladogram, which places coelacanths as the sister group of porolepiforms + lungfishes, with the rhizodonts + tetrapods and osteolepiforms as successive sister groups of this clade. Characters of uncertain polarity are considered in the light of this cladogram. A comparison with recently published cladograms shows that none are completely compatible with the results from this study.  相似文献   

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