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1.
Scanning electron microscopy and transmitted light microscopy are used in a palynological study of Lophosoria, Metaxya, Sphaeropteris, Alsophila, and Nephelea of the tree fern family Cyatheaceae. The monotypic American genera Lophosoria and Metaxya each have a unique spore morphology which reinforces the taxonomic distinctness of these genera as indicated by their other characters. All investigated paleotropical species of Sphaeropteris develop a single type of perine characterized by coarse, pointed projections. In the neotropics, the Sphaeropteris horrida group shares this perine type, whereas all other neotropical Sphaeropteris species appear to have a different kind of perine with fine hair-like processes. The exine in paleotropical Sphaeropteris appears uniformly unsculptured, whereas in the neotropics several exine morphologies are found. In Alsophila all investigated neotropical species and the vast majority of the paleotropical species are characterized by a basically ridged perine morphology and an unsculptured exine. In several paleotropical Alsophila species, however, a perine with hair-like processes similar to those in neotropical Sphaeropteris is found, and the exine in several species is variously pitted. In at least one paleotropical Alsophila species, the porate exine morphology is indistinguishable from that in the neotropical genus Cnemidaria. The spores of the American genus Nephelea are similar to those of the majority of Alsophila species in ridged perine morphology and unsculptured exine. Several new instances of atypical spore numbers per sporangium are reported in Sphaeropteris and Alsophila. These and the palynological data are discussed in a taxonomic framework. The spore morphology in these genera is consistent with Tryon's recent generic revision of the family.  相似文献   

2.
A preliminary phylogenetic analysis is presented forLomariopsis based on sequence data from the chloroplast intergenic spacertrnL-trnF. The analysis includes 27 (60%) of the approximately 45 species in the genus. A strict consensus of six most parsimonious trees supports two main clades—theSorbifolia-group and theJapurensis-group—previously proposed based on heteroblastic leaf development. TheSorbifolia-group is entirely neotropical and includes all the Antillean species. The species in this clade had either smooth or crested spores, but the tree was ambiguous whether these spore types define two separate clades. TheJapurensis-group consists of two clades, one primarily neotropical and the other entirely paleotropical. Within the neotropical clade nests a clade of two African species, which have long-spiny spores typical of the neotropical clade and unlike those found in the African-Madagascan clade. The occurrence of these two species in Africa is best explained by longdistance spore dispersal of their ancestral species from the neotropics to Africa. Within the paleotropical clade of theJapurensis-group, a clade of three African species is nested among seven species from Madagascar (all the species from that island). Within the genus as a whole, a derived character—the abortion of the rachis apex and its replacement by the distal lateral pinna assuming a terminal position—was found to have evolved separately in each of the four species with this kind of leaf apex. A scanning electron microcope study of the spores revealed five types, and a transformation series for these different types is proposed. Characters of spore morphology and heteroblastic leaf development agreed with many of the clades in the phylogenetic tree. This study represents the first phylogeny for the genus.  相似文献   

3.
Fifteen species of neotropical and three species of paleotropical bats are known either to roost in or to make tents in over 80 species of vascular plants. We summarize the current knowledge of bat-tent architecture, report two new styles of tents (conical and apical) from the Paleotropics, compare the similarity in tents constructed, or used, by neotropical and paleotropical bats, and consider possible functions of tents. Seven styles of tents are known from the Neotropics, three (conical, palmate umbrella, and apical tents) are known from both the Neo- and the Paleotropics, and one (stem tent) is unique to the Paleotropics. In the Neotropics tent-roosting and/or tent-making appears to be a behavior unique to the diverse microchiropteran family Phyllostomidae (subfamily Phyllostomatinae: tribe Stenodermatini), and in the Paleotropics two members of the megachiropteran family Pteropodidae and one member of the microchiropteran family Vespertilionidae are known to construct or roost in tents. Despite the variety of plant taxa used by bats in tent construction, there appears to be a limited number of different leaf forms that can be altered by bats and used as tents. We suggest that the similarity in tent architecture observed among the neotropical and paleotropical bats is a consequence of convergence in leaf morphology among forest understory plants. The congruence in tent-making/roosting behavior observed in members of the Stenodermatini and the Pteropodidae (genusCynopterus) suggests a phylogenetic influence on these behaviors. The similarity in tent-making and/or tent-roosting behavior and life-history traits (small, <70 g, mostly foliage-roosting frugivores) among these divergent neotropical and paleotropical taxa supports a convergence hypothesis in which members of these groups have become ecological equivalents. Although actual tent-making has been observed in only one bat species to date, we suggest that the principal selective force leading to the evolution of tent-making is a polygynous mating system whereby males construct tents to gain access to females. Tents in turn provide resources that offer protection from predators and inclement weather.  相似文献   

4.
We evaluated the boundaries among Nymphoides (Menyanthaceae) species in Africa, a region where the genus has received relatively little attention. We gathered morphological data from seeds using light and scanning electron microscopy, and we conducted molecular phylogenetic analyses using nuclear sequence data from the internal transcribed spacer (ITS) region. Morphological and molecular features distinguished six species and affirmed their respective geographic ranges. No African specimens were attributable to Nymphoides indica, even though this paleotropical species previously had been understood to grow in Africa. We establish the new combination Nymphoides senegalensis (G. Don) Tippery, based on an established African basionym, to accommodate the specimens formerly identified as N. indica. Phylogenetic analyses resolved two distinct clades containing African species. The majority of African species are closely related to neotropical species, with which they share similar petal ornamentation. The morphologically distinct N. ezannoi shares floral and phylogenetic similarity with species from North America and Asia. Results presented here support prior hypotheses that allopolyploid species in the Americas may have originated from one or more parental lineages in Africa. Seed morphological characters remain some of the most reliable features for identifying species, particularly for herbarium specimens lacking observable floral characters.  相似文献   

5.
The moth genus Omiodes (Crambidae) comprises about 80 species and has a circumtropical distribution, with the type species, O. humeralis, occurring in Central America. In Hawaii, there are 23 native species currently placed in Omiodes, but this classification has been disputed, and they were previously placed in various other genera. We used molecular phylogenetic analyses to assess the monophyly of Omiodes as a whole, and specifically of the Hawaiian species, as well as their geographic origins and possible ancestral host plants. Mitochondrial (COI) and nuclear (wingless, EF1α, CAD, and RPS5) DNA was sequenced for Omiodes from Hawaii, South America, and Australasia, along with many other putative outgroup spilomeline genera. Phylogenies were estimated using maximum likelihood and Bayesian inference, and various taxon and character datasets. With the exception of two paleotropical species (O. basalticalis and O. odontosticta, whose placement was unresolved) all Hawaiian, paleotropical and neotropical Omiodes, including the type species, fell within a well-supported, monophyletic clade. Although the center of diversity for Omiodes is in the Neotropics, its center of origin was ambiguous, due to poor resolution of the basal splits between paleotropical and neotropical Omiodes. Very low genetic divergence within the Hawaiian Omiodes suggests a relatively recent colonization of the Hawaiian Islands. Phylogenies constructed using all codon positions were poorly resolved at intergeneric levels, and did not reveal a sister taxon for Omiodes, but phylogenies constructed using only first and second codon positions suggested a close relationship with Cnaphalocrocis. The monophyly of several other spilomeline genera is also discussed.  相似文献   

6.
The neotropical genus Rhynchanthera (Melastomataceae, Microlicieae) is revised, and 15 of the 84 proposed taxa are recognized; two species are excluded from the genus. The group consists of subshrubs and shrubs with usually purple flowers in thyrsoid inflorescences of uniparous or biparous cymes. It is characterized by androecia with five antepetalous staminodia in addition to the five fertile stamens, and - in most species - dimorphism of the stamens, with one strikingly longer than the other four. The plants always are covered by at least some simple glandular hairs. The majority of the species of Rhynchanthera occur in south-central Brazil, however, the range of the genus extends from southern Mexico to Bolivia and Paraguay. All species grow in wet places in open scrub or savanna vegetation. Micromorphological features of the seeds have been investigated and support the traditional placement of Rhynchanthera in the Microlicieae where it is closest to Microlicia, Lavoisiera , and Trembleya. Two taxa are illustrated with drawings, and the distribution of all is mapped.  相似文献   

7.
Neotropical rainforests host a rich community of fruit-eating animals, among them neotropical scatter-hoarding rodents that bury seeds in soil. These animals perform an important community-building process because the seeds germinate and establish seedlings away from the parent plant. In three recent studies, researchers have demonstrated a comparable role for paleotropical rodents in southeast Asia. With the discovery that a frugivorous kangaroo behaves similarly to its neotropical rodent counterpart, a new level has been reached in our understanding of the evolution of tropical forests.  相似文献   

8.
The phenology and pollination ecology of three native fig species were studied in southeastern Brazil. Populations displayed continual syconia production, with one species showing intra-tree flowering asynchrony. Pollination of the fig flowers was necessary for the development of the syconia; lack of pollination induced abortion of syconia. All three species follow the general pattern of pollination known for figs, but the behavior of the pollinator wasps, Pegoscapus spp., differed in some aspects from those of other neotropical and paleotropical fig wasps, mainly with respect to pollen loading and unloading during pollination. The longevity of Pegoscapus wasps outside the syconium was about two days.  相似文献   

9.
Patterns of capsule development and methods of seed dispersal are described and compared for 16 neotropical species of Dalechampia. In 15 species all the capsules in a single inflorescence develop simultaneously. In one species, D. spathulata, the capsules develop sequentially. I suggest that the difference between D. spathulata and the other species is the result of the fact that D. spathulata occurs in a low-light, rainforest environment, whereas the other species grow in high-light environments. Sequential development of capsules appears to reduce the loss of seeds to seed predators in species that occur in light-limited environments. The seeds of all 16 species of Dalechampia are dispersed by explosive dehiscence of the capsules. Within the genus there are several different adaptations that increase the average dispersal distance for the seed crop.  相似文献   

10.
We explore the phylogeny of the polygrammoid ferns using nucleotide sequences derived from three plastid loci for each of 98 selected species. Our analyses recovered four major monophyletic lineages: the loxogrammoids, two clades consisting of taxa restricted to the Old World, and a largely neotropical clade that also includes the pantropical Grammitidaceae. The loxogrammoid lineage diverges first and is sister to a large clade comprising the three remaining species-rich lineages. One paleotropical clade includes the drynarioid and selligueoid ferns, whereas the second paleotropical clade includes the platycerioids, lepisoroids, microsoroids, and their relatives. The grammitids nest within the neotropical clade, although the sister taxon of this circum-tropic, epiphytic group remains ambiguous. Microsorum and Polypodium, as traditionally defined, were recovered as polyphyletic. The relatively short branch lengths of the deepest clades contrast with the long branch lengths leading to the terminal groups. This suggests that the polygrammoid ferns arose through an old, rapid radiation. Our analysis also reveals that the rate of substitution in the grammitids is remarkably higher relative to other polygrammoids. Disparities in substitution rate may be correlated with one or more features characterizing grammitids, including species richness, chlorophyllous spores, and an extended gametophytic phase.  相似文献   

11.
The evolution of marine neotropical shallow water species is expected to have been greatly affected by physical events related to the emergence of the Central American Isthmus. The anomuran crab Megalobrachium, a strictly neotropical porcellanid genus, consists of four species in the West Atlantic (WA) and nine in the East Pacific (EP). Dispersal is limited to a relatively short planktonic phase, which lasts approximately two weeks. We obtained DNA sequences of three mitochondrial and two nuclear genes of all but one species of Megalobrachium to construct a time‐calibrated phylogeny of the genus and its historical phylogeography, based on the reconstruction of ancestral areas. The topology of the phylogenetic trees of Megalobrachium produced by Bayesian Inference (BI) and Maximum Likelihood (ML) were virtually congruent. The genus is monophyletic with respect to other porcellanids. Ancestral area reconstruction indicates that it arose in the eastern Pacific 18 million years ago and diversified into at least 13 species that are currently formally recognized and three additional species indicated by our data. Most morphological variation appears to have followed phylogenetic differentiation, though some cryptic speciation has also occurred. Four geminate clades in this genus implicate the gradual emergence of the Central American Isthmus in this diversification, but events preceding the final separation of the oceans as well as within‐ocean events after the cessation of water connections were also important.  相似文献   

12.
To elucidate chloroplast genome evolution within neotropical-paleotropical bamboos, we fully characterized the chloroplast genome of the woody bamboo Guadua angustifolia. This genome is 135,331 bp long and comprises of an 82,839-bp large single-copy (LSC) region, a 12,898-bp small single-copy (SSC) region, and a pair of 19,797-bp inverted repeats (IRs). Comparative analyses revealed marked conservation of gene content and sequence evolutionary rates between neotropical and paleotropical woody bamboos. The neotropical herbaceous bamboo Cryptochloa strictiflora differs from woody bamboos in IR/SSC boundaries in that it exhibits slightly contracted IRs and a faster substitution rate. The G. angustifolia chloroplast genome is similar in size to that of neotropical herbaceous bamboos but is ~3 kb smaller than that of paleotropical woody bamboos. Dissimilarities in genome size are correlated with differences in the lengths of intergenic spacers, which are caused by large-fragment insertion and deletion. Phylogenomic analyses of 62 taxa yielded a tree topology identical to that found in preceding studies. Divergence time estimation suggested that most bamboo genera diverged after the Miocene and that speciation events of extant species occurred during or after the Pliocene.  相似文献   

13.
New species of the neotropical genus Neolindus Scheerpeltz (Coleoptera, Staphylinidae). Five new species of the neotropical genus Neolindus from the Peruvian Amazon region and from Brazil (Rio de Janeiro) are described.  相似文献   

14.
Summary  A new monotypic genus and a new species of Monimiaceae, Grazielanthus arkeocarpus from the Brazilian Atlantic coastal forest are described, illustrated and compared with morphologically related taxa. The new taxon occurs in the State of Rio de Janeiro in the central coastal plain and was collected in the Po?o das Antas Biological Reserve, municipality of Silva Jardim (22°30′– 22°33′S; 42°14′– 42°19′W). The new taxon is represented by dioecious climbing shrubs of the sub-canopy that have urceolate, four-lobed flowers and a fleshy hypanthium that is closed until the fruit ripens. When ripe, the hypanthium ruptures irregularly and the fruitlets are exposed. The relationships between the new genus and other neotropical (Hennecartia J. Poiss. and Macrotorus Perkins) and paleotropical (Palmeria F. Muell.) genera are discussed.  相似文献   

15.
Callipteris is a pantropical fern genus defined by two synapomorphies of its rhizome scales: 1) dark-castaneous to black borders, and 2) bifid marginal teeth. This monograph treats 15 neotropical species ofCallipteris that are further defined by the synapomorphy of anastomosing veins (free-veined species of the genus occur in the Neotropics and elsewhere). Three species are newly described here; the remaining 12 were previously classified inDiplazium. All the species ofCallipteris grow on wet forest floors at 100–2300 m. In the Neotropics the genus occurs from Guatemala to Bolivia, northern Brazil, and the Lesser Antilles. It has two centers of species richness. The first is the Chocó region on the western side of the Andes in Colombia and northwestern Ecuador. This region contains eight species, five of which are endemic. The second center is the mountains of Costa Rica and Panama, where six species occur, three of which are endemic. Only one species, an endemic, occurs in the Lesser Antilles in Martinique, St. Vincent, and Grenada. Four species occur only on the eastern side of the Andes, and these apparently represent at least two separate dispersal events from the western side of the Andes.  相似文献   

16.
Douglas C. Daly 《Brittonia》2005,57(2):118-122
Dacryodes edilsonii Daly (Burseraceae) is one of at least 14 still undescribed neotropical species in the genus; it is also one of a large number of new species emerging from intensified botanical exploration of the Brazilian state of Acre in southwestern Amazonia. The new species is easily distinguished from most other Neotropical species of the genus by its usually densely long-pubescent petiole, rachis, petiolules, and abaxial midvein.  相似文献   

17.
The genus Pycnoporus forms a group of four species known especially for producing high redox potential laccases suitable for white biotechnology. A sample of 36 Pycnoporus strains originating from different geographical areas was studied to seek informative molecular markers for the typing of new strains in laboratory culture conditions and to analyse the phylogeographic relationships in this cosmopolitan group. ITS1-5.8S-ITS2 ribosomal DNA and partial regions of β-tubulin and laccase lac3-1 gene were sequenced. Phylogenetic trees inferred from these sequences clearly differentiated the group of Pycnoporus cinnabarinus strains from the group of Pycnoporus puniceus strains into strongly supported clades (100% bootstrap value). Molecular clustering based on lac 3-1 sequences enabled the distribution of Pycnoporus sanguineus and Pycnoporus coccineus through four distinct, well supported clades and sub-clades. A neotropical sub-clade, grouping the P. sanguineus strains from French Guiana and Venezuela, corresponded to P. sanguineus sensu stricto. A paleotropical sub-clade, clustering the strains from Madagascar, Vietnam and New Caledonia, was defined as Pycnoporus cf. sanguineus. The Australian clade corresponded to P. coccineus sensu stricto. The Eastern Asian region clade, clustering the strains from China and Japan, formed a P. coccineus-like group. Laccase gene (lac 3-1) analysis within the Pycnoporus species can highlight enzyme functional diversity associated with biogeographical origin.  相似文献   

18.
The genus Platycerium is one of the few pantropical epiphytic fern genera with six species in Afro-Madagascar, 8-11 Australasian species, and a single species in tropical South America. Nucleotide sequences of four chloroplast DNA markers are employed to reconstruct the phylogeny of these ferns and to explore their historical biogeography. The data set was designed to resolve conflicting hypotheses on the relationships within the genus that were based on previous phylogenetic studies exploring morphological evidence. Our results suggest a basal split of Platycerium into two well-supported clades. One clade comprises species occurring in Africa, Madagascar, and South America, whereas the second clade contains exclusively Australasian species. The latter clade is further divided into a clade corresponding to P. bifurcatum and its putative segregates and a clade of seven species occurring from Indochina throughout the Malesian region to New Guinea and Australia. The Afro-Madagascan clade includes a clade of two species found in tropical Africa and a clade of four species that includes three species endemic to Madagascar. The single neotropical species of this genus, P. andinum, is nested within the Afro-Madagascan clade but is not closely related to any extant species.  相似文献   

19.
In neotropical Rubiaceae, nine new species for Brazil and one new generic section are described. Six new combinations and two new statuses are proposed, and the author citation ofPsychotria racemosa is corrected.Augusta is expanded to includeLindenia with nomenclatural adjustments, andAnthospermopsis is raised from a section to a genus.  相似文献   

20.
Six new species of the Australian myrmecophilous ptinid genus Polyplocotes are described from South Australia. Three are from the deserts of central Australia, one from the Franklin Islands in the Great Australian Bight, one from Eyre Peninsula and one from the Riverland region. Morphologically, the majority of these new species are conventional Polyplocotes , but two are less typical. The characters uniting the genus are explored in the discussion, and comparisons are made to related genera. Although the six new species described here have not been observed in the field, the species of this genus are known to be myrmecophilous, and ant – beetle interactions similar to those seen in other spider beetles might occur between these new species and their host ants.  相似文献   

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