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1.
The 34 valid species of avian Plasmodium are listed with their authorities and type-hosts. Plasmodium species are also listed by the avian family in which they occur and by the number of avian families and species which they parasitise. A key to the subgenera of Plasmodium occurring in birds is presented. The distribution of the parasites by the Wallacean life zones is discussed; Plasmodium records in birds from the Australian zone is sharply lower than for any other life zone. 相似文献
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Alpine plants of the eastern Qinghai-Tibetan plateau (Sichuan, China) are developed under long-lasting grazing by wild and domestic yaks. Among morphological features of plants, life forms may reflect their adaptation to grazing. We studied life-form composition of four typical communities within the alpine belt (3930–3960 m a.s.l.) subjected to grazing of various intensity: alpine fen (heavily grazed), alpine shrub meadow (heavily grazed), Spiraea alpina thicket (grazed), and Rhododendron thicket (practically not grazed). The following morphological traits were studied: (1) life form according to Raunkiaer, (2) life form according to Serebryakov, (3) canopy structure, and (4) rate of lateral spreading. We derived life-form spectra based on (1) the number of species per life form and (2) the cumulative abundance of species which have the same life form. One-way ANOVA and nonparametric ANOVA were run to test for significance of differences between spectra. The studied communities differed significantly by the proportion of different life forms. The main life forms are caudex and short rhizome hemicryptophytes, nonclonal species, or species with a low rate of lateral spreading. Therophytes made up 10–11% of the communities except in Rhododendron thickets, where such were absent. These life forms can indicate grazing in the study area. 相似文献
4.
The myobiid genus Acanthophthirius Perkins, to date comprising four subgenera, is reviewed and divided into just two subgenera, the nominate subgenus and Myotimyobia Fain. The male genital shield and female opisthogastric sclerites, which are here considered to be part of female genitalia, are adopted as the criteria for dividing the subgenera. These structures are essentially the same in form and position in the subgenus Acanthopthirius in its revised sense, while they are both more heterogeneous in species of the redefined subgenus Myotimyobia. The subgenera Acanthophthirius Fain and Chiromyobia Fain are thought to represent species-groups in the nominate subgenus, named respectively the etheldredae and miniopteri groups. The following one new subspecies and 11 new species are described: A. (A.) womersleyi eptesicus, A. (A.) glauconycteris, A. (A.) mauritaniensis, A. (A.) philetoris, A. (A.) otonycteris, A. (A.) steatocaudatus, A. (A.) nyctophilis, A. (M.) vagus, A. (M.) longus A. (M.) baueris, A. (A.) hesperopteris (female only) and A. (M.) pixonixeos (female only). A. (M.) hanensis is synonymised with A. (M.) namurensis, and A. (M.) capacini is emended to A. (M.) capaccinii and relegated to a subspecies of A. (M.) myotis. All the known and new species are assigned to their respective subgenera and shown in a table. Incongruent host-relationships of some of the mites are clarified, although not completely solved, by the introduction of the new classification for the subgenera. 相似文献
5.
Molecular phylogeny of the hyperdiverse genus Sarcophaga (Diptera: Sarcophagidae), and comparison between algorithms for identification of rogue taxa
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Eliana Buenaventura Daniel Whitmore Thomas Pape 《Cladistics : the international journal of the Willi Hennig Society》2017,33(2):109-133
The hyperdiverse genus Sarcophaga Meigen, with about 890 valid species arranged within 169 subgenera, accounts for almost half of the diversity of the subfamily Sarcophaginae. Current phylogenetic hypotheses for this genus are poorly supported or based on small taxon sets, or both. Here, we use molecular data from the genes COI and 28S to reconstruct the phylogeny of Sarcophaga based on the most comprehensive sampling for the group to date: 144 species from 47 subgenera, including representatives from all regional faunas for the first time. Of the total sequences of Sarcophaga used in the present study, 94.7% were newly generated. The secondary structure of the D1–D3 expansion segments of 28S is presented for the first time for the family Sarcophagidae, and is used in a multiple sequence alignment. Branch support and tree resolution increased remarkably through rogue taxa identification and exclusion. Rogue behaviour was explained mostly as a missing data problem. The RogueNaRok web service and the algorithms chkmoves, IterPCR and prunmajor implemented in the computer program TNT were equally good at identifying critical rogue species, but chkmoves and IterPCR also identified rogue clades. Pruning rogues increased the number of monophyletic subgenera in consensus trees from one to six out of 19 subgenera with more than one representative species. Bayesian inference, maximum‐likelihood and parsimony analyses recovered more monophyletic subgenera after the removal of rogue taxa, with parsimony showing the largest improvements in branch support and resolution. Although with low support, Nearctic taxa were found to be the earliest diverging lineages, followed by a subsequent diversification of Old World faunas, which is in agreement with currently available evidence of a New World origin and early diversification of Sarcophaga. 相似文献
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Chloroplast DNA (cpDNA) restriction site variation was examined in 32 species, representing five subgenera, of Bromus (Poaceae). Thirty-seven phylogenetically informative restriction sites were detected. Cladistic analysis of the restriction site data produced a single most-parsimonious tree of 50 steps. The cladogram indicated two major clades within the genus. One clade included B. trinii of subgenus Neobromus and species of subgenus Ceratochloa. The other was composed of subgenera Festucaria, Stenobromus, and Bromus. Within the second clade, species of subgenus Festucaria appeared in three lineages. The second clade also contained an assemblage of species belonging to subgenera Stenobromus and Bromus in a separate lineage. There was very little resolution of relationships in this assemblage since several species appeared individually in separate lineages. The cpDNA phylogenetic hypothesis did not separate species of subgenera Stenobromus and Bromus into well-defined clades as circumscribed by morphology and cytogenetics. The cpDNA tree is in agreement with the phylogenetic scheme based on traditional data in that: 1) subgenera Neobromus and Ceratochloa were the first to diverge, while Bromus and Stenobromus diverged later; 2) within the genus Bromus species with small chromosomes are ancestral; and 3) subgenera Bromus and Stenobromus probably originated from similar ancestors as Festucaria. The tree based on cpDNA data does not support that: 1) subgenera Neobromus and Ceratochloa did not have a common origin; 2) subgenus Festucaria is monophyletic; and 3) subgenera Stenobromus and Bromus are distinct entities. The mean nucleotide sequence divergence values between pairs of subgenera ranged from p = 0.0 to 0.9. These values suggest that cpDNA evolution in Bromus is slow. 相似文献
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MARTIN FIKÁČEK ALEXANDER PROKIN ROBERT B. ANGUS ALEXANDER PONOMARENKO YANLI YUE DONG REN JAKUB PROKOP 《Systematic Entomology》2012,37(3):420-447
We performed a phylogenetic analysis focused on the hydrophiloid family Helophoridae (Coleoptera: Polyphaga) in order to test the phylogenetic position of selected Mesozoic fossils assigned to the Hydrophiloidea. The analysis is based on 92 characters of larvae and adults, and includes all extant subgenera of Helophorus and representatives of all other extant hydrophiloid families. Based on this analysis, we provide additional evidence for the monophyly of the helophorid lineage containing the families Helophoridae, Georissidae and Epimetopidae, as well as the first hypothesis on the phylogenetic relationships within Helophorus, revealing three main clades: Lihelophorus, Rhopalohelophorus and the clade of sculptured small subgenera; the subgenera Helophorus s.str., Gephelophorus, Trichohelophorus and Transithelophorus are recognized as paraphyletic or polyphyletic. Inclusion of fossil species in the analysis reveals the Mesozoic genera Hydrophilopsia Ponomarenko, Laetopsia Fiká?ek et al. (adult forms) and Cretotaenia Ponomarenko (larval form) as basal extinct clades of the helophorid lineage, the former genus Mesosperchus Ponomarenko as containing probable stem taxa of Helophorus and the former genus Mesohelophorus Ponomarenko as a member of the Helophorus clade containing extant sculptured subgenera. The extant subgenus Thaumhelophorus syn.nov. is synonymized with Rhopalohelophorus. Our results show that the family Helophoridae may be dated back to the late Jurassic (c. 150 Ma) and the extant clades of Helophorus back to the Early Cretaceous (c. 136 Ma). The basal groups of Helophorus and the supposed basal extinct lineages of the helophorid lineages are shown to be aquatic as adults. A single origin of trichobothria and ventral hydrophobic pubescence in the common ancestor of the Hydrophiloidea is hypothesized, indicating ancestral aquatic habits in the adult stage for the whole Hydrophiloidea. 相似文献
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Forcipomyia (Pterobosca) hutsoni n.sp. is described and figured from adults of both sexes and from putatively identified larvae and pupae. The species is common on Aldabra Atoll in the Indian Ocean. Most adult females were taken from the wings of Odonata. Immature stages were found in Pandanus leaf axils and are the first to be described for the subgenus Pterobosca. Characters of the three stages show that biting midges of this subgenus are most closely related to the subgenera Phytohelea, Trichohelea and Rhynchoforcipomyia. The subgenera Thyridomyia, Synthyridomyia and probably Blantonia fall in a second section of the genus, while Lasiohelea forms a third and intermediate section. 相似文献
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Biosystematic relationships among species assigned to three subgenera of the genus Dicentra were investigated with respect to hybridization and chromosomal constitution and fertility of the hybrids. Four species of subgenus Dicentra, D. formosa, D. eximia, D. nevadensis, and D. peregrina, were intercrossed in various ways to form diploid, triploid, and tetraploid hybrids. Hybrids at the tetraploid level in this subgenus invariably were highly fertile. Triploid hybrids, as expected, were mostly very sterile. Diploid hybrids varied in this respect, but none was highly fertile. Crosses with two of the remaining four species of subgenus Dicentra produced no hybrids, but abundant seed was obtained in one instance. The two species of the subgenus Chrysocapnos, D. chrysaniha and D. ochroleuca, cross to produce a partially fertile tetraploid hybrid, but cross-pollinations involving these species with those of other subgenera failed. The single species of subgenus Hedycapnos, D. spectablis (diploid) produced no hybrids when cross-pollinated with members of the other two sections. These results are fully concordant with presumed affinities based on morphological similarity In addition, preliminary results of hybridization between the monocotyledonous D. peregrina and a number of dicotyledonous species of Dicentra are reported. 相似文献
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LaurI. Kaila 《Systematic Entomology》1999,24(2):139-169
Abstract. The classification of the gelechioid family Elachistidae (Lepidoptera) is revised on the basis of a phylogenetic analysis. Pee-Wee analysis of 131 characters of adult and pupal morphology and larval mode of life, coded for seventy elachistid species, results in a classification with three recognized genera: Perittia, Stephensia and Elachista. Elachista is further divided into four subgenera. The phylogenetic relationships of the genera and subgenera are (Perittia (Stephensia ((E. sg. Dibrachia (E. sg. Hemiprosopa, E. sg. Aphelosetia)) (E. sg. Elachista)))). Twenty-four new generic synonyms and thirty-eight new generic combinations of species are proposed. A checklist is given for the species of Elachistidae in their revised generic combinations, including nine new synonymies. Due to secondary homonymy, Elachista dasycara nom. n. is proposed as a new name for Eurynome albella Chambers. 相似文献
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In the tribe Cynareae the genus Carlina is a well limited taxon. The sequence of leaves and involucral bracts, and the form of heads are important characters for identification. The genus is classified into the subgenera Carlowizia, Lyrolepis, and Carlina. The ancestral subgenera Carlowizia and Lyrolepis are endemits of the Canary islands respectively the south Aegean islands. The very variable species of the Mediterranean-Central European-West Asian subgenus Carlina are divided into sect. Corymbosae, sect. Mitina, sect. Carlina, and sect. Heteracantha. These sections are well distinguished by several morphological and anatomical features. A new species C. kurdica) is described from north-west Iraq. 相似文献
14.
Passiflora L. has more than 575 species distributed especially in the Neotropics. The chromosome number variation in the genus is highly congruent with its main subgenera, but its basic chromosome number (x) and the underlying events responsible for this variation have remained controversial. Here, we provide a robust and well-resolved time-calibrated phylogeny that includes 102 taxa, and by means of phylogenetic comparative methods (PCM) we tested the relative importance of polyploidy and dysploidy events to Passiflora karyotype evolution and diversification. Passiflora arose 42.9 Mya, with subgenus diversification at the end of the Palaeogene (Eocene-Oligocene). The basic chromosome number of the genus is proposed as x?=?6, and a strong recent diversification found in the Passiflora subgenus (Miocene) correlated to genome size increase and a chromosome change from n?=?6 to n?=?9 by ascending dysploidy. Polyploidy, conversely, appeared restricted to few lineages, such as Astrophea and Deidamioides subgenera, and did not lead to diversification increases. Our findings suggest that ascending dysploidy provided a great advantage for generating long-term persistent lineages and promoting species diversification. Thus, chromosome numbers/genome size changes may have contributed to morphological/ecological traits that explain the pattern of diversification observed in the genus Passiflora. 相似文献
15.
RAD sequencing resolved phylogenetic relationships in European shrub willows (Salix L. subg. Chamaetia and subg. Vetrix) and revealed multiple evolution of dwarf shrubs
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Natascha Dorothea Wagner Susanne Gramlich Elvira Hörandl 《Ecology and evolution》2018,8(16):8243-8255
The large and diverse genus Salix L. is of particular interest for decades of biological research. However, despite the morphological plasticity, the reconstruction of phylogenetic relationships was so far hampered by the lack of informative molecular markers. Infrageneric classification based on morphology separates dwarf shrubs (subg. Chamaetia) and taller shrubs (subg. Vetrix), while previous phylogenetic studies placed species of these two subgenera just in one largely unresolved clade. Here we want to test the utility of genomic RAD sequencing markers for resolving relationships at different levels of divergence in Salix. Based on a sampling of 15 European species representing 13 sections of the two subgenera, we used five different RAD sequencing datasets generated by Ipyrad to conduct phylogenetic analyses. Additionally we reconstructed the evolution of growth form and analyzed the genetic composition of the whole clade. The results showed fully resolved trees in both ML and BI analysis with high statistical support. The two subgenera Chamaetia and Vetrix were recognized as nonmonophyletic, which suggests that they should be merged. Within the Vetrix/Chamaetia clade, a division into three major subclades could be observed. All species were confirmed to be monophyletic. Based on our data, arctic‐alpine dwarf shrubs evolved four times independently. The structure analysis showed five mainly uniform genetic clusters which are congruent in sister relationships observed in the phylogenies. Our study confirmed RAD sequencing as a useful genomic tool for the reconstruction of relationships on different taxonomic levels in the genus Salix. 相似文献
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Zhi-Qiang Zhang 《Experimental & applied acarology》1995,19(3):139-146
Variance and covariance of ovipositional rates and developmental rates in the Phytoseiidae were analysed using comparative methods which consider phylogenetic effects. Nested analysis of variance showed that mean ovipositional rates and developmental rates of phytoseiid mites varied significantly between subfamilies, among genera within subfamilies, among subgenera within genera and among species within subgenera. For example, the mean ovipositional rate (eggs per day) was higher in the Amblyseiinae (2.04) than in the Phytoseiinae (1.39) and within the Amblyseiinae, it was higher in the genus Phytoseiulus (2.66) than in Amblyseius (1.80). Regressions using mean values of subgenera or higher taxa to account for phylogenetic effects showed significant correlation between mean ovipositional rates and developmental rates. The implications of this analysis for selecting species for future comparative analysis of phytoseiid life history variation are discussed. 相似文献
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Isoprenoid (isoprene and monoterpenes) emission is widespread among oak species. A number of studies investigating the emission by oak species around the world are here compiled. These studies indicate that isoprenoids are reliable taxonomical markers at subgenera level. Isoprene-emitters belong to the subgenera Lobateae, Quercus sensu strictu, and Protobalanus and are therefore found in every continent of the northern hemisphere. Non-emitters and monoterpene-emitters belong to Cerris and Ilex (= Schlerophyllodris) subgenus, respectively, and are particularly, if not solely, diffused in the Mediterranean area. The results suggest that the taxonomical assignment of some species should be reviewed. Experimental data indicate that isoprenoids have a protective role against environmental stresses and a strong antioxidant action. On the basis of the present knowledge I speculate that in oaks the ancestral trait is the emission of isoprene, and that the other traits evolved as adaptive response to the environment. 相似文献
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BURAK K. PEKIN ROY S. WITTKUHN MATTHIAS M. BOER CRAIG MACFARLANE PAULINE F. GRIERSON 《Austral ecology》2012,37(3):330-338
Frequent fires reduce the abundance of woody plant species and favour herbaceous species. Plant species richness also tends to increase with decreasing vegetation biomass and cover due to reduced competition for light. We assessed the influence of variable fire histories and site biomass on the following diversity measures: woody and herbaceous species richness, overall species richness and evenness, and life form evenness (i.e. the relative abundance or dominance among six herbaceous and six woody plant life forms), across 16 mixed jarrah (Eucalyptus marginata) and marri (Corymbia calophylla) forest stands in south‐west Australia. Fire frequency was defined as the total number of fires over a 30‐year period. Overall species richness and species evenness did not vary with fire frequency or biomass. However, there were more herbaceous species (particularly rushes, geophytes and herbs) where there were fewer shrubs and low biomass, suggesting that more herbaceous species coexist where dominance by shrubs is low. Frequently burnt plots also had lower number and abundance of shrub species. Life form evenness was also higher at both high fire frequency and low biomass sites. These results suggest that the impact of fire frequency and biomass on vegetation composition is mediated by local interactions among different life forms rather than among individual species. Our results demonstrate that measuring the variation in the relative diversity of different woody and herbaceous life forms is crucial to understanding the compositional response of forests and other structurally complex vegetation communities to changes in disturbance regime such as increased fire frequency. 相似文献
19.
JOHN F. REINERT RALPH E. HARBACH IAN J. KITCHING 《Zoological Journal of the Linnean Society》2009,157(4):700-794
The phylogeny and classification of tribe Aedini are delineated based on a cladistic analysis of 336 characters from eggs, fourth‐instar larvae, pupae, adult females and males, and immature stage habitat coded for 270 exemplar species, including an outgroup of four species from different non‐aedine genera. Analyses of the data set with all multistate characters treated as unordered under implied weights, implemented by TNT version 1.1, with values of the concavity constant K ranging from 7 to 12 each produced a single most parsimonious cladogram (MPC). The MPCs obtained with K values of 7–9 were identical, and that for K = 10 differed only in small changes in the relationships within one subclade. Because values of K < 7 and > 10 produced large changes in the relationships among the taxa, the stability of relationships exemplified by the MPC obtained from the K = 9 analysis is used to interpret the phylogeny and classification of Aedini. Clade support was assessed using parsimony jackknife and symmetric resampling. Overall, the results reinforce the patterns of relationships obtained previously despite differences in the taxa and characters included in the analyses. With two exceptions, all of the groups represented by two or more species were once again recovered as monophyletic taxa. Thus, the monophyly of the following genera and subgenera is corroborated: Aedes, Albuginosus, Armigeres (and its two subgenera), Ayurakitia, Bothaella, Bruceharrisonius, Christophersiomyia, Collessius (and its two subgenera), Dahliana, Danielsia, Dobrotworskyius, Downsiomyia, Edwardsaedes, Finlaya, Georgecraigius (and its two subgenera), Eretmapodites, Geoskusea, Gilesius, Haemagogus (and its two subgenera), Heizmannia (and subgenus Heizmannia), Hopkinsius (and its two subgenera), Howardina, Hulecoeteomyia, Jarnellius, Kenknightia, Lorrainea, Macleaya, Mucidus (and its two subgenera), Neomelaniconion, Ochlerotatus (subgenera Chrysoconops, Culicelsa, Gilesia, Pholeomyia, Protoculex, Rusticoidus and Pseudoskusea), Opifex, Paraedes, Patmarksia, Phagomyia, Pseudarmigeres, Rhinoskusea, Psorophora (and its three subgenera), Rampamyia, Scutomyia, Stegomyia, Tanakaius, Udaya, Vansomerenis, Verrallina (and subgenera Harbachius and Neomacleaya), Zavortinkius and Zeugnomyia. In addition, the monophyly of Tewarius, newly added to the data set, is confirmed. Heizmannia (Mattinglyia) and Verrallina (Verrallina) were found to be paraphyletic with respect to Heizmannia (Heizmannia) and Verrallina (Neomacleaya), respectively. The analyses were repeated with the 14 characters derived from length measurements treated as ordered. Although somewhat different patterns of relationships among the genera and subgenera were found, all were recovered as monophyletic taxa with the sole exception of Dendroskusea stat. nov. Fifteen additional genera, three of which are new, and 12 additional subgenera, 11 of which are new, are proposed for monophyletic clades, and a few lineages represented by a single species, based on tree topology, the principle of equivalent rank, branch support and the number and nature of the characters that support the branches. Acartomyia stat. nov. , Aedimorphus stat. nov. , Cancraedes stat. nov. , Cornetius stat. nov. , Geoskusea stat. nov. , Levua stat. nov. , Lewnielsenius stat. nov. , Rhinoskusea stat. nov. and Sallumia stat. nov., which were previously recognized as subgenera of various genera, are elevated to generic status. Catageiomyia stat. nov. and Polyleptiomyia stat. nov. are resurrected from synonymy with Aedimorphus, and Catatassomyia stat. nov. and Dendroskusea stat. nov. are resurrected from synonymy with Diceromyia. Bifidistylus gen. nov. (type species: Aedes lamborni Edwards) and Elpeytonius gen. nov. (type species: Ochlerotatus apicoannulatus Edwards) are described as new for species previously included in Aedes (Aedimorphus), and Petermattinglyius gen. nov. (type species: Aedes iyengari Edwards) and Pe. (Aglaonotus) subgen. nov. (type species: Aedes whartoni Mattingly) are described as new for species previously included in Aedes (Diceromyia). Four additional subgenera are recognized for species of Ochlerotatus, including Oc. (Culicada) stat. nov. (type species: Culex canadensis Theobald), Oc. (Juppius) subgen. nov. (type species: Grabhamia caballa Theobald), Oc. (Lepidokeneon) subgen. nov. (type species: Aedes spilotus Marks) and Oc. (Woodius) subgen. nov. (type species: Aedes intrudens Dyar), and seven are proposed for species of Stegomyia: St. (Actinothrix) subgen. nov. (type species: Stegomyia edwardsi Barraud), St. (Bohartius) subgen. nov. (type species: Aedes pandani Stone), St. (Heteraspidion) subgen. nov. (type species: Stegomyia annandalei Theobald), St. (Huangmyia) subgen. nov. (type species: Stegomyia mediopunctata Theobald), St. (Mukwaya) subgen. nov. (type species: Stegomyia simpsoni Theobald), St. (Xyele) subgen. nov. (type species: Stegomyia desmotes Giles) and St. (Zoromorphus) subgen. nov. (type species: Aedes futunae Belkin). Due to the unavailability of specimens for study, many species of Stegomyia are without subgeneric placement. As is usual with generic‐level groups of Aedini, the newly recognized genera and subgenera are polythetic taxa that are diagnosed by unique combinations of characters. The analysis corroborates the previous observation that ‘Oc. (Protomacleaya)’ is a polyphyletic assemblage of species. 相似文献
20.
Patterns of tree species richness in relation to environment in southeastern New South Wales,Australia 总被引:1,自引:0,他引:1
Abstract We present regression models of species richness for total tree species, two growth forms, rainforest trees (broadleaf evergreens) and eucalypts (sclerophylls), and two large subgenera of Eucalyptus. The correlative models are based on a data set of 166 tree species from 7208 plots in an area of southeastern New South Wales, Australia. Eight environmental variables are used to model the patterns of species richness, four continuous variables (mean annual temperature, rainfall, radiation and plot size), plus four categorical factors (topographic position, lithology, soil nutrient level and rainfall seasonality). Generalized linear modelling with curvilinear and interaction terms, is used to derive the models. Each model shows a significant and differing response to the environmental predictors. Maximum species richness of eucalypts occurs at high temperatures, and intermediate rainfall and radiation conditions on ridges with aseasonal rainfall and intermediate nutrient levels. Maximum richness of rainforest species occurs at high temperatures, intermediate rainfall and low radiation in gullies with summer rainfall and high nutrient levels. The eucalypt subgenera models differ in ways consistent with experimental studies of habitat preferences of the subgenera. Curvilinear and interaction terms are necessary for adequate modelling. Patterns of richness vary widely with taxonomic rank and growth form. Any theories of species diversity should be consistent with these correlative models. The models are consistent with an available energy hypothesis based on actual evapotranspiration. We conclude that studies of species richness patterns should include local (e.g. soil nutrients, topographic position) and regional (e.g. mean annual temperature, annual rainfall) environmental variables before invoking concepts such as niche saturation. 相似文献