Ants of the genus Myrmecia Fabricius: A review of the species groups and their phylogenetic relationships (Hymenoptera: Formicidae: Myrmeciinae)

Abstract. Myrmecia Fabricius is revised at species-group level. Nine groups are recognized: those of M.aberrans, M.cephalotes, M.gulosa, M.mandibularis, M.nigrocincta, M.picta, M.pilosula, M.tepperi and M. urens. A key to the species groups is provided, and worker diagnoses, illustrations and species lists are given for each. Eight groups are constituted much as in the previous classification of John Clark, but defined using new characters. Phylogenetic relationships are investigated, with six cladograms derived from four sets of data, each with a different outgroup. The most plausible cladograms suggest that: (1) the aberrans group is the sister group to the others; (2) the pilosula, tepperi and mandibularis groups constitute a monophyletic assemblage, though monophyly of the first two is not confirmed; (3) the gulosa, nigrocincta, urens and picta groups constitute a monophyletic assemblage, though monophyly of the picta group is not confirmed; (4) the phylogenetic position of the cephalotes group is unclear.     

A phylogeny of Packera (Senecioneae; asteraceae) based on internal transcribed spacer region sequence data and a broad sampling of outgroups

A phylogeny of Packera is presented based on sequence data from the internal transcribed spacer region of nuclear ribosomal DNA of 26 species (28 populations) of Packera and 23 outgroup taxa, including representatives of all three subtribes of the Senecioneae. The results support a Mexican origin for Packera, with its closest relatives found among Old World taxa in the subtribe Senecioninae, such as Senecio jacobaea and Pericallis. Packera species from the west coast of the United States, previously included in the section Bolanderi of Greenman, are part of a basal assemblage including species of Greenman's Mexican section Sanguisorboidei. The rest of Packera separates into two sister groups, one containing species from the Arizona-New Mexico region and the other containing more geographically diverse taxa. Among the outgroups, New World Senecio species are monophyletic and two Tussilaginoid assemblages are strongly supported; the Tephroseroid group (Tephroseris and Sinosenecio) plus Petasites combine with the Luina complex to form a clade of north temperate taxa, and the four Mexican genera (Psacalium, Robinsonecio, Barkleyanthus, and Pittocaulon) form a monophyletic group.     

Phylogenetic analysis of the generaCladonia andCladina (Cladoniaceae, lichenizedAscomycota)

A cladistic analysis of 44 species of the generaCladina andCladonia is presented.Pycnothelia papillaria, Cladia aggregata andC. retipora were used as outgroup taxa. The consensus of all equally parsimonious trees suggests a common ancestral origin for species inCladonia andCladina while the generaPycnothelia andCladia cluster outside this group. The results do not support distinction ofCladina at genus level although it is distinguished as a monophyletic group but within the genusCladonia. The current sectional division ofCladonia is not supported. SectionsCocciferae andHelopodium are best supported but even these groups as currently delimited seem to in include elements that are more closely related to species of the other sections, e.g.C. carneola of sect.Cocciferae andC. pityrophylla of sect.Helopodium. Sections such asUnciales andPerviae seem to be artificial assemblages. In general the evolutionary scheme of the genus seems to be more complicated than revealed by the current sectional division.     

A molecular phylogeny of Hebeloma species from Europe

In order to widen the scope of existing phylogenies of the ectomycorrhizal agaric genus Hebeloma a total of 53 new rDNA ITS sequences from that genus was generated, augmented by sequences retrieved from GenBank, and analysed using Bayesian, strict consensus and neighbour joining methods. The lignicolous Hebelomina neerlandica, Gymnopilus penetrans, and two species of Galerina served as outgroup taxa. Anamika indica, as well as representatives of the genera Hymenogaster and Naucoria, were included to test the monophyly of Hebeloma, which is confirmed by the results. Hebeloma, Naucoria, Hymenogaster and Anamika indica cluster in a strongly supported monophyletic hebelomatoid clade. All trees largely reflect the current infrageneric classification within Hebeloma, and divide the genus into mostly well-supported monophyletic groups surrounding H. crustuliniforme, H. velutipes, H. sacchariolens, H. sinapizans, and H. radicosum, with H. sarcophyllum being shown at an independent position; however this is not well supported. The section Indusiata divides with strong support into three groups, the position of the pleurocystidiate Hebeloma cistophilum suggests the possible existence of a third subsection within sect. Indusiata. Subsection Sacchariolentia is raised to the rank of section.     

Phylogenetics of Chinese Dryopteris (Dryopteridaceae) based on the chloroplast rps4-trnS sequence data

Dryopteris is one of the largest and most taxonomically complex fern genera in the Dryopteridaceae, with 127 species occurring throughout temperate, sub-temperate, subtropical, and tropical China. Investigations of the evolutionary relationships of a subset of these Chinese Dryopteris species, using DNA sequence-based methods, specifically tested the monophyly of the genus and the validity of the previous subgeneric classifications. Sixty species of Dryopteris, four closely related non-Dryopteris and three species of Arachniodes, were used as outgroup taxa. The rps4-trnS region of the chloroplast genome was sequenced in these species for the first time. Both maximum parsimony (MP) and neighbor-joining (NJ) analyses identified six polyphyletic clades that contained Dryopteris species. These results were supported by a Bayesian analysis of the same data set. The phylogenetic patterns strongly suggest the polyphyletic status of Dryopteris; the monophyletic groupings of the species do not correspond with either Fraser-Jenkins [In: Bull Brit Mus (Nat Hist) Bot 14(3):183–218, 1986} or Wu (In: Flora Reipublica Popularis Sinicae Tomus 5 (1) pp 1–241, 2000] subgeneric classification of Dryopteris, except in a few specific cases. This work represents the first molecular systematic analyses of Chinese Dryopteris, and we propose the next steps necessary to recognize new subgenera of the genus.     

Molecular evidence for species level divergence in African Nile Crocodiles Crocodylus niloticus (Laurenti, 1786)

Relationships of the newly discovered dwarf crocodiles from Mauritania were inferred from mitochondrial 12S sequences. Specimens from 13 different Crocodylus niloticus populations (from East Africa, West Africa and Madagascar) were compared. Additional representatives of the genus Crocodylus (one from Africa and one from Australia), the African genus Osteolaemus and the South American alligatorid Paleosuchus palpebrosus (as outgroup) were included in the analysis. Maximum-likelihood and Bayesian analyses yielded relationships that were strikingly different from currently prevailing phylogenetic hypotheses. Both analyses consistently revealed two groups, one consisting of the monophyletic West- and Central African populations and the other of a paraphyletic group containing the East African and Madagascan populations. High genetic divergence between those groups indicates separation on the species level. Furthermore ‘C’ cataphractus is clearly shown not to be a member of the genus Crocodylus. The resulting nomenclatural changes are discussed. To cite this article: A. Schmitz et al., C. R. Palevol 2 (2003).     

董棕和短穗鱼尾葵光合效率日变化及其与生理生态因子的关系

利用美国产CI-340便携式光合测定系统,对董棕和短穗鱼尾葵的光合日变化特性进行了测定,通过相关分析和通径分析探讨净光合速率与生理生态因子的关系,并利用二项式数学模型对其光合光响应曲线进行了拟合.结果表明:(1)2种棕榈植物的净光合速率日变化都呈现不对称的双峰曲线,有明显的"午休"现象,董棕的午休深度及时长明显大于短穗鱼尾葵,其第二峰出现的时间比短穗鱼尾葵延后2h,这可能主要由于两者在气孔导度及蒸腾速率等自身生理因子活性方面的差异所致.(2)影响董棕和短穗鱼尾葵净光合速率日变化的主要决定生理因子均为胞间CO2浓度,但主要限制因子董棕为气孔导度,短穗鱼尾葵为叶面温度;主要决定生态因子董棕为光合有效辐射,短穗鱼尾葵为空气CO2浓度,主要限定因子两者均为空气相对湿度.(3)董棕和短穗鱼尾葵均具有较高的光补偿点和光饱和点,属强耐阳性植物,但鱼尾葵相对较低,更适于北移引种栽培.     

Molecular phylogeny of the speciose vole genus Microtus (Arvicolinae, Rodentia) inferred from mitochondrial DNA sequences

Voles of the genus Microtus represent one of the most speciose mammalian genera in the Holarctic. We established a molecular phylogeny for Microtus to resolve contentious issues of systematic relationships and evolutionary history in this genus. A total of 81 specimens representing ten Microtus species endemic to Europe as well as eight Eurasian, six Asian and one Holarctic species were sequenced for the entire cytochrome b gene (1140 bp). A further 25 sequences were retrieved from GenBank, providing data on an additional 23, mainly Nearctic, Microtus species. Phylogenetic analysis of these 48 species generated four well-supported monophyletic lineages. The genus Chionomys, snow voles, formed a distinct and well-supported lineage separate from the genus Microtus. The subgenus Microtus formed the strongest supported lineage with two sublineages displaying a close relationship between the arvalis species group (common voles) and the socialis species group (social voles). Monophyly of the Palearctic pitymyid voles, subgenus Terricola, was supported, and this subgenus was also subdivided into two monophyletic species groups. Together, these groupings clarify long-standing taxonomic uncertainties in Microtus. In addition, the "Asian" and the Nearctic lineages reported previously were identified although the latter group was not supported. However, relationships among the main Microtus branches were not resolved, suggesting a rapid and potentially simultaneous radiation of a widespread ancestor early in the history of the genus. This and subsequent radiations discernible in the cytochrome b phylogeny, show the considerable potential of Microtus for analysis of historical and ecological determinants of speciation in small mammals. It is evident that speciation is an ongoing process in the genus and that the molecular data provides a vital insight into current species limits as well as cladogenic events of the past.     

A cladistic analysis ofAnisopappus (Asteraceae: Inuleae)

A cladistic analysis of the genusAnisopappus (Asteraceae: Inuleae) has been undertaken. A hypothesis of species interrelationships in the genus is presented for the first time. The analysis also includedArctotis (Arctoteae), used as outgroup, and five additional genera from theInuleae: Geigeria, Calostephane, Asteriscus, Buphthalmum, Pulicaria, andInula. It is concluded thatAnisopappus is a monophyletic group situated at the base of the tribe, diagnosed by, e.g., their obtuse stylar sweeping-hairs. The species with acute sweeping-hairs were found to be derived within the genus. Problems concerning species delimitation, biogeography and character evolution in the genus are briefly discussed.     

Taxonomic studies on marine triclads (Turbellaria,Tricladida, Maricola)

The genus Procerodes forms a heterogeneous assemblage of taxa. Although it is premature to attempt phylogenetic weighting of the characters, the genus contains three well delimited subgroups, one with a subantarctic, panaustral distribution, one world-wide in distribution, and one occurring principally in the northern hemisphere. Outside of these subgroups, species in this genus are problematic since a number of their features also occurs in other procerodids. All recognized groups exhibit a wide distributional range. Many of the world-wide taxonomic relations lie on the species level and some at the level of genera. Poor dispersal capacity of extant species of Procerodes suggests that the biogeographic patterns may be very old.     

Phylogeny of <Emphasis Type="Italic">Litsea</Emphasis> and related genera (Laureae-Lauraceae) based on analysis of <Emphasis Type="Italic">rpb2</Emphasis> gene sequences

The relationship between Litsea and related genera is currently unclear. Previous molecular studies on these taxa using cpDNA and nrITS were unable to produce well-resolved phylogenetic trees. In this study, we explored the potential of the rpb2 gene as a source of molecular information to better resolve the phylogenetic analysis. Although rpb2 was believed to be a single-copy gene, our cloning results showed that most species examined possessed several copies of these sequences. However, the genetic distance among copies from any one species was low, and these copies always formed monophyletic groups in our molecular trees. Our phylogenetic analyses of rpb2 data resulted in better resolved tree topologies compared to those based on cpDNA or nrITS data. Our results show that monophyly of the genus Litsea is supported only for section Litsea. As a genus, Litsea was shown to be polyphyletic. The genera Actinodaphne and Neolitsea were resolved as monophyletic groups in all analyses. They were also shown to be sisters and closer to the genus Lindera than to the genus Litsea. Our results also revealed that the genus Lindera is not a monophyletic group.     

32种杜鹃花属植物在迁地保育条件下的自交研究

迁地保育条件下的杜鹃花属植物自交可育性一直缺乏系统的比较研究,该文对5亚属13亚组32种杜鹃花属植物的自交进行了数据采集与分析,初步揭示了迁地保育条件下杜鹃花属植物自交育性特征。结果表明:(1)自交可育与不育是杜鹃花属植物有性生殖中的两个并存现象,自交能育型种类或多于不育型。在受试的32种杜鹃花中,自交不育型10种、弱可育型5种、可育型7种、高可育型10种,其中27种的自交育性为首次报道,涵盖包括杜鹃亚属杜鹃组(sect.Rhododendron)和马银花亚属(subgen.Azaleastrum)及常绿杜鹃亚属(subgen.Hymenanthes)中银叶杜鹃亚组(subsect.Argyrophylla)等5个亚组在内的未被研究的类群。(2)通过与自然授粉有关育性指标的比较,发现不同种类的自交可育性指标有大幅度降低及增高这两类截然不同的现象,从而提出了自交可能是部分杜鹃花属植物的适应策略,或者对不利环境及其媒介条件的主动响应。(3)在云锦杜鹃亚组(subsect.Fortunea)这个被认为最原始的杜鹃花类群中,具备从自交不育到高可育的所有类型,并可能由此奠定整个杜鹃花属的遗传基础,而类群与种类分布的不同区域气候环境长期直接的或通过影响传粉媒介间接的作用,则可能是最终塑造该属植物自交育性多样化的外部动力。(4)该文还依据有关自交的研究结果,对杜鹃花属植物的迁地保育、育种、相关学科发展进行了讨论,并认为后合子期败育的理论不能完美地解释自交不能坐果的现象,而多倍体似不会导致自交不育。     

Phylogeny and phylogeography of the Mediterranean species of the parasitic ant genus <Emphasis Type="Italic">Chalepoxenus</Emphasis> and its <Emphasis Type="Italic">Temnothorax</Emphasis> hosts

We analysed the phylogenetic and phylogeographic relationships of four Mediterranean species of the rare slave-making ant genus Chalepoxenus and eleven of its about 20 Temnothorax host species by sequencing the mitochondrial Cytochrome Oxidase I and II genes. Neighbour-Joining, Maximum Parsimony and Bayesian analyses based on 1320 bp indicate that the genus Chalepoxenus constitutes a monophylum. In all three analyses, C. kutteri from Southwest Europe and the workerless, “degenerate slavemaker” C. brunneus from North Africa form a monophyletic group. C. muellerianus and C. tauricus, distributed in Southern Europe and Ukraine, respectively, form a monophylum in the Neighbour-Joining and the Maximum Parsimony analysis. In our limited set of only 11 of several hundred Temnothorax species, T. flavicornis forms the sister group of Chalepoxenus. Our study further indicates paraphyly of the genus Temnothorax with respect to Chalepoxenus. Moreover, the results suggest that speciation in this slave-making genus is possibly caused by the formation of host races as different Chalepoxenus species use different hosts, and some samples seem to cluster by host species rather than by geographical distance. Received 5 September 2006; revised 17 March 2007; accepted 23 March 2007.     

Phenetic studies in Nuphar Sm. (Nymphaeaceae):variation in sect. Nuphar

Previous taxonomic assessments of the hydrophytic genus Nuphar Sm. (Nymphaeaceae) have inadequately considered the range of morphological variation existing in the genus. A comprehensive statistical analysis of morphological features among the recognized taxa of Nuphar is presented here, first using 10 fruit characters to delimit the separation of two infrageneric groups of taxa, and secondly using 31 characters to quantify the morphological variation found within sect. Nuphar. Results from combined phenetic analyses provided empirical support for recognition of two infrageneric groups of species in the genus (largely by fruit, stigmatic disk margin, neck, and stigmatic disk size) and for separation of taxa within sect. Nuphar (by leaf size, and fruit disk and neck size). Statistical analyses demonstrate that extensive variation in ranges of character states exists among sect. Nuphar taxa. However, a suite of qualitative and quantitative characters can be used to recognize five species and three subspecies within this predominantly Old World assemblage.     

Phylogenetic relationships betweenVicia faba (Fabaceae) and related species inferred from chloroplasttrnL sequences

The chloroplasttrnL intron from 46 differentVicia accessions, representing five of the nine sections of the genusVicia subg.Vicia sensuMaxted (1991a) were amplified by the Polymerase Chain Reaction (PCR) using oligonucleotide primers homologous to conserved regions intrnL. The products fell into two distinct groups; those of approximately 250 nt and those of around 450 nt in length. Of these, products from 17 differentVicia species were cloned and their nucleotide sequences determined. Multiple alignments were assembled and phylogenetic trees constructed by the weighted least-squares distance method. ALathyrus latifolius trnL intron sequence was used as an outgroup. The resulting trees clearly group and separate the sectt.Narbonensis, Bithynica andFaba species but were less able to distinguish species from sectt.Hypechusa andPeregrinae. Based on these sequence data,V. faba appears to be more distant from sect.Narbonensis than sectt.Hypechusa andPeregrinae. The results are in general agreement with a recent treatment ofVicia subg.Vicia (Maxted 1993) and lend further support to placingV. faba in the monospecific sect.Faba.     

Molecular phylogeny of terrestrial holocarpic endoparasitic peronosporomycetes, <Emphasis Type="Italic">Haptoglossa</Emphasis> spp., inferred from 18S rDNA

Phylogenetic relationships of seven isolates of the genus Haptoglossa parasitic on terrestrial nematodes within the Peronosporomycetes were analyzed using 18S rDNA sequence data with 21 peronosporomycetes, 2 marine stramenopilous flagellates, and 2 hyphochytridiomycetes. The marine stramenopilous flagellates and hyphochytridiomycetes were used as the outgroup. All Haptoglossa isolates formed a monophyletic clade and clustered with the marine genus Eurychasma. The clade of Haptoglossa and Eurychasma formed a sister-group to the clade that consisted of all other peronosporomycetes. These results suggest that the genus Haptoglossa and other terrestrial peronosporomycetes included in the two subclasses, the Saprolegniomycetidae and the Peronosporomycetidae, might have originally adapted to the terrestrial environment individually. In the maximum-likelihood (ML) analysis, the Haptoglossa clade was divided into three subclades, one aplanosporic species clade and two zoosporic species clades. Phylogenetic analyses of combined 18S rDNA and cox2 genes among five species of Haptoglossa supported the results of the ML analysis using 18S rDNA and suggested that zoosporic species may be separated into two lineages. This topology of the analysis may suggest that aplanosporic species diverged from zoosporic species.     

Phylogenetic analysis ofIridaceae with parsimony and distance methods using the plastid generps4

A molecular phylogeny of the familyIridaceae based on the plastid generps4 was obtained using both parsimony and distance methods. Thirty-four species were examined together with eight outgroup species. Results show that theIridaceae are monophyletic, and thatIsophysis is likely to be the earliest emerging genus. SubfamilyIxioideae plus the generaAristea andNivenia form a strongly supported clade. Within subfam.Iridoideae, the tribeIrideae includes the genusBobartia (of disputed position), and the tribeMariceae includesCypella. The division ofIridoideae into tribes is consistent with their geographical distribution.     

Phylogenetic relationships in Peniocereus (Cactaceae) inferred from plastid DNA sequence data

The phylogenetic relationships of Peniocereus (Cactaceae) species were studied using parsimony analyses of DNA sequence data. The plastid rpl16 and trnL-F regions were sequenced for 98 taxa including 17 species of Peniocereus, representatives from all genera of tribe Pachycereeae, four genera of tribe Hylocereeae, as well as from three additional outgroup genera of tribes Calymmantheae, Notocacteae, and Trichocereeae. Phylogenetic analyses support neither the monophyly of Peniocereus as currently circumscribed, nor the monophyly of tribe Pachycereeae since species of Peniocereus subgenus Pseudoacanthocereus are embedded within tribe Hylocereeae. Furthermore, these results show that the eight species of Peniocereus subgenus Peniocereus (Peniocereus sensu stricto) form a well-supported clade within subtribe Pachycereinae; P. serpentinus is also a member of this subtribe, but is sister to Bergerocactus. Moreover, Nyctocereus should be resurrected as a monotypic genus. Species of Peniocereus subgenus Pseudoacanthocereus are positioned among species of Acanthocereus within tribe Hylocereeae, indicating that they may be better classified within that genus. A number of morphological and anatomical characters, especially related to the presence or absence of dimorphic branches, are discussed to support these relationships.     

Molecular phylogeny of the fern genus Elaphoglossum (Elaphoglossaceae) based on chloroplast non-coding DNA sequences: contributions of species from the Indian Ocean area

We performed a phylogenetic analysis of the fern genus Elaphoglossum using two non-coding chloroplast spacers: trnL-trnF and rps4-trnS. The sampling includes 123 species, of which 80 have not been previously sequenced, and for the first time includes species from Africa and the Indian Ocean area. The results of this expanded study largely agree with an earlier molecular study based on a smaller group of neotropical species and with the morphology-based classification of Mickel and Atehortua. We found, however, that some infrageneric groups such as section Elaphoglossum are not monophyletic. Besides section Elaphoglossum pro parte, we recognize six sections: two new monospecific, unnamed sections, and the previously established sections Lepidoglossa, Squamipedia, Amygdalifolia, and "Subulate-scaled clade." We divide the subulate-scaled clade into subsection Setosa (hydathodes present) and Polytrichia (hydathodes absent), and section Elaphoglossum is divided into subsections Platyglossa and Pachyglossa, two groups that do not appear to be supported by any single morphological character. In general, however, the main clades are supported by morphology. Finally, we discuss the species of the Indian Ocean region and their affinities with the neotropical ones. Out of the 11 species pairs postulated by Moran and Smith on the basis of morphology, two are well supported (E. eximium-E. aubertii; E. piloselloides-E. spatulatum) and three are not supported (E. ciliatum-E. humbertii; E. muscosum-E. poolii; E. paleaceum-E. deckenii), and two remain unresolved (E. erinaceum-E. hybridum; E. glabellum-E. acrostichoides) because our molecular markers were not variable enough. Four species pairs could not be tested because specimens were lacking. Unsupported species pairs are best interpreted as morphological convergences. Two additional species pairs are proposed: E. cuspidatum-E. succisaefolium; E. doanense-E. hornei. Placement of the species from the Indian Ocean suggests that at least 13 long-distance dispersal events occurred between the Neotropics and the Indian Ocean-Africa.