A morphological re-evaluation of the taxonomic status of the genus Pellegriniodendron (Harms) J. Léonard (Leguminosae–Caesalpinioideae–Detarieae) and its inclusion in Gilbertiodendron J. Léonard

The taxonomic status of the genus Pellegriniodendron J. Léonard (Leguminosae, Caesalpinioideae), which consists in one tree species endemic to West Central tropical Africa, is re-evaluated. Based on our morphological comparison and on published phylogenetic studies, we conclude that P. diphyllum should be included within the genus Gilbertiodendron J. Léonard, and the new combination Gilbertiodendron diphyllum (Harms) Estrella & Devesa is proposed. A lectotype for Macrolobium reticulatum, synonym of G. diphyllum, is also designated. The species is fully described and illustrated, and a distribution map is also presented.     

First Record of Culicoides oxystoma Kieffer and Diversity of Species within the Schultzei Group of Culicoides Latreille (Diptera: Ceratopogonidae) Biting Midges in Senegal

The Schultzei group of Culicoides Latreille (Diptera: Ceratopogonidae) is distributed throughout Africa to northern Asia and Australasia and includes several potential vector species of livestock pathogens. The taxonomy of the species belonging to this species group is confounded by the wide geographical distribution and morphological variation exhibited by many species. In this work, morphological and molecular approaches were combined to assess the taxonomic validity of the species and morphological variants of the Schultzei group found in Senegal by comparing their genetic diversity with that of specimens from other geographical regions. The species list for Senegal was updated with four species: Culicoides kingi, C. oxystoma, C. enderleini and C. nevilli being recorded. This is the first record of C. oxystoma from Africa south of Sahara, and its genetic relationship with samples from Israel, Japan and Australia is presented. This work provides a basis for ecological studies of the seasonal and spatial dynamics of species of this species group that will contribute to better understanding of the epidemiology of the viruses they transmit.     

Integrative taxonomy and preliminary assessment of species limits in the Liolaemus walkeri complex (Squamata,Liolaemidae) with descriptions of?three?new species from Peru

Species delimitation studies based on integrative taxonomic approaches have received considerable attention in the last few years, and have provided the strongest hypotheses of species boundaries. We used three lines of evidence (molecular, morphological, and niche envelopes) to test for species boundaries in Peruvian populations of the Liolaemus walkeri complex. Our results show that different lines of evidence and analyses are congruent in different combinations, for unambiguous delimitation of three lineages that were “hidden” within known species, and now deserve species status. Our phylogenetic analysis shows that L. walkeri, L. tacnae and the three new species are strongly separated from other species assigned to the alticolor-bibronii group. Few conventional morphological characters distinguish the new species from closely related taxa and this highlights the need to integrate other sources of data to erect strong hypothesis of species limits. A taxonomic key for known Peruvian species of the subgenus Lioalemus is provided.     

Morphometric analysis of six Gerbillus species (Rodentia,Gerbillinae) from Tunisia

Size and shape changes in the skull of the genus Gerbillus were investigated using geometric morphometrics. Six species from Tunisia were studied (G. gerbillus, G. campestris, G. nanus, G. tarabuli, G. simoni and G. latastei). Statistical analyses of shape variability allowed us to discriminate three morphological groups which are congruent with the three groups suggested by previous morphological and molecular studies. However, our results contrast with previous molecular investigations. In fact, according to results obtained by the use of principal component analysis, canonical variate analysis and UPGMA, we found a higher degree of divergence between the subgenus Dipodillus and the other two subgenera Gerbillus and Hendecapleura. This fact suggests that the morphometric differences observed among species within the genus Gerbillus are not mainly related to phylogeny. To reconciliate the molecular and morphological approaches, we propose a hypothesis of differential rates of phenotypic evolution in the genus Gerbillus. In this view, the species belonging to the subgenus Dipodillus evolved apomorphic features of the skull likely related to a higher degree of habitat specialization. By contrast, the more generalist Gerbillus and Hendecapleura subgenera show less differentiated plesiomorphic morphology.     

Phylogenetic relationships,subdivision, and biogeography of the cyprinid tribe Labeonini (sensu ) (Teleostei: Cypriniformes), with comments on the implications of lips and associated structures in the labeonin classification

The Labeonini (sensu Rainboth, 1991) is a tribe of the subfamily Cyprininae, the largest subfamily of Cypriniformes. With around 400 species in 34 genera, this tribe is widely distributed in the freshwaters of tropical Africa and Asia. Most species are adapted to fast-flowing streams and rivers, and exhibit unique morphological modifications associated with their lips and other structures around the mouth. The monophyly of this tribe has been tested and generally accepted in previous morphological and molecular studies. The major objectives of this study were to reconstruct the phylogenetic relationships within the tribe Labeonini, test its monophyly and explore the taxonomic subdivisions, intrarelationships and biogeography of the group. The value of the morphological characters associated with the lips and other associated structures in the taxonomic classification of labeonins was also discussed. Nucleotide sequences (3867 bp) of four unlinked nuclear loci were obtained from 51 species in 18 Labeonini genera from throughout the range of the tribe. Maximum parsimony, partitioned maximum likelihood and partitioned Bayesian analyses were used for phylogenetic inference from combined and separate gene data sets. Based on our results, the monophyly of Labeonini was well supported. Two major clades could be recovered within the tribe. Three subclades could further be recognized from the first clade. These clades/subclades are not consistent with groupings of any of previous workers using either morphological or molecular characters for phylogenetic inference. Only five currently recognized genera in this analysis are monophyletic. The similarity between some lips and associated structures (e.g. suctorial discs) of labeonins may due to convergence or parallelism instead of common ancestry. Labeonins of Southeast Asia, India and China are closely related to each other; the multiple clades of African taxa do not form a single monophyletic group, indicating multiple, independent dispersal events of labeonins into Africa from Asia.     

Developmental variations among Panagrolaimid nematodes indicate developmental system drift within a small taxonomic unit

Comparative studies of nematode embryogenesis among different clades revealed considerable variations. However, to what extent developmental differences exist between closely related species has mostly remained nebulous. Here, we explore the correlation between phylogenetic neighborhood and developmental variation in a restricted and morphologically particularly uniform taxonomic group (Panagrolaimidae) to determine to what extent (1) morphological and developmental characters go along with molecular data and thus can serve as diagnostic tools for the definition of kinship and (2) developmental system drift (DSD; modifications of developmental patterns without corresponding morphological changes) can be found within a small taxonomic unit. Our molecular approaches firmly support subdivision of Panagrolaimid nematodes into two monophyletic groups. These can be discriminated by distinct peculiarities in early embryonic cell lineages and a mirror-image expression pattern of the gene skn-1. This suggests major changes in the logic of cell specification and the action of DSD in the studied representatives of the two neighboring nematode taxa.     

Phylogenetic Patterns of Geographical and Ecological Diversification in the Subgenus Drosophila

Colonisation of new geographic regions and/or of new ecological resources can result in rapid species diversification into the new ecological niches available. Members of the subgenus Drosophila are distributed across the globe and show a large diversity of ecological niches. Furthermore, taxonomic classification of Drosophila includes the rank radiation, which refers to closely related species groups. Nevertheless, it has never been tested if these taxonomic radiations correspond to evolutionary radiations. Here we present a study of the patterns of diversification of Drosophila to test for increased diversification rates in relation to the geographic and ecological diversification processes. For this, we have estimated and dated a phylogeny of 218 species belonging to the major species groups of the subgenus. The obtained phylogenies are largely consistent with previous studies and indicate that the major groups appeared during the Oligocene/Miocene transition or early Miocene, characterized by a trend of climate warming with brief periods of glaciation. Ancestral reconstruction of geographic ranges and ecological resource use suggest at least two dispersals to the Neotropics from the ancestral Asiatic tropical disribution, and several transitions to specialized ecological resource use (mycophagous and cactophilic). Colonisation of new geographic regions and/or of new ecological resources can result in rapid species diversification into the new ecological niches available. However, diversification analyses show no significant support for adaptive radiations as a result of geographic dispersal or ecological resource shift. Also, cactophily has not resulted in an increase in the diversification rate of the repleta and related groups. It is thus concluded that the taxonomic radiations do not correspond to adaptive radiations.     

An integrative approach for species delimitation in the spider genus Grammostola (Theraphosidae,Mygalomorphae)

The mygalomorph genus Grammostola (family Theraphosidae) is endemic to South America. The species Grammostola anthracina is one of the largest spiders in Uruguay and reputed to be the longest lived tarantula in the world. This nominal species has two distinct colour morphs comprising black and reddish‐brown forms with controversial taxonomic status. Here, we present a phylogenetic study based on molecular characters (cytochrome c oxidase subunit I) of haplotypes of G. anthracina and closely related species. Our analysis together with new morphological data and biogeographical information indicates that the two morphs of G. anthracina constitute different species that are not sister to each other. Consequently, a new species, Grammostola quirogai is described, diagnosed and illustrated to encompass the black morph. Phylogenetic relationships and new taxonomic characters for Grammostola species included in this study are discussed.     

The chemotaxonomic value of the diglucoside anthrone homonataloside B in the genus Aloe

The chemotaxonomic value of the only known diglucoside anthrone from Aloe, homonataloside B, is discussed. This compound has been detected in only 14 species in a chemotaxonomic survey of 380 Aloe species. The homonataloside B-accumulating species are only found in Africa with none of the Malagasy endemics producing this compound. A summary of the morphological variation is presented together with the taxonomic distribution of this unique anthrone. The representatives of this distinct chemotype occupy disparate positions in the largely artificial hierarchy of the present classification system. Species included in this chemotype provide chemical evidence of hybridisation in Aloe.     

Sibling species of fragrant orchids (Gymnadenia: Orchidaceae, Magnoliophyta) in Russia

Recent molecular phylogenetic studies of the genus Gymnadenia have demonstrated that it contains sibling taxa, i.e., species that are hardly distinguishable according to morphological traits, yet are phylogenetically rather distant and distinctly distinguishable by molecular methods, which is a rare phenomenon for angiosperms. By sequencing the ITS1-5.8S rDNA-ITS2 fragment the presence of G. densiflora was confirmed for Russia. Our data supported a high degree of genetic differentiation between G. conopsea s. str. and G. densiflora, which confirms their taxonomic rank of species. Morphological analysis has shown that the features that are best for the discrimination between these two species in Northwestern Russia are the length of the lower bract, length of the mid-lobe of the lip, and width of leaves. The ecological and phenological differentiation between G. conopsea s. str. and G. densiflora is briefly reviewed. The ITS sequence variation in these species has been analyzed; the molecular genetic differences of the G. conopsea individuals from the eastern part of the distribution area have been discovered for the first time. Different taxonomic interpretations of Gymnadenia phylogenetic tree topology taking into account the presence of sibling species are discussed in general.     

Rolling into the deep of the land planarian genus <Emphasis Type="Italic">Choeradoplana</Emphasis> (Tricladida,Continenticola, Geoplanidae) taxonomy

The land planarian genus Choeradoplana (Plathelminthes, Tricladida) is currently integrated by 13 species. In previous works, morphological variation in its type species, Choeradoplana iheringi, was reported, but no attempt to test whether it is just a single species has been made yet. In order to disentangle the taxonomy of this species and further members of the genus, we sampled new specimens and combined morphological and molecular data and also have evaluated the performance of diverse methods of molecular species delimitation. Our data point to the presence of two cryptic species named C. iheringi, plus two new species, all hidden under the same general appearance. An in-depth morphological study of the specimens allowed detection of diagnostic morphological traits in each species, for which we also propose a molecular diagnosis. This integrative taxonomic study demonstrates once again the usefulness of molecular tools to weigh minor morphological characteristics and thus reveal the existence of species that would otherwise remain cryptic. However, under certain parameters, the molecular methods may over-split species with a high genetic structure, maybe pointing to incipient speciation. This makes critical the use of these methods combined with a comprehensive morphological approach. We also present a comprehensive phylogenetic tree including most Choeradoplana species. The tree, well supported, allows making some preliminary inferences on the evolution of the group and its historical biogeography.     

TWO NEW SOREDIATE TAXA OFPELTIGERA

Examination of specimens ofPeltigera didactyla, from Africa, Asia, Europe and North America revealed that this sorediate species includes three entities that can be separated on morphological characters. A new species,P. lambinonii, is described from East Africa, and a new combinationP. didactylavar.extenuata, is proposed to accommodate morphs from mesic forest habitats in Asia, Europe and North America. Despite this taxonomic reduction,P. didactylavar.didactylaremains a ubiquitous taxon. The former two taxa often produce methyl gyrophorate, which can co-occur with traces of gyrophoric acid. These tridepsides were only rarely detected in var.didactyla; their occasional presence seems to be best explained by hybridization. The taxonomic and ecological significance of these substances is discussed.     

Integrating a Numerical Taxonomic Method and Molecular Phylogeny for Species Delimitation of Melampsora Species (Melampsoraceae,Pucciniales) on Willows in China

The species in genus Melampsora are the causal agents of leaf rust diseases on willows in natural habitats and plantations. However, the classification and recognition of species diversity are challenging because morphological characteristics are scant and morphological variation in Melampsora on willows has not been thoroughly evaluated. Thus, the taxonomy of Melampsora species on willows remains confused, especially in China where 31 species were reported based on either European or Japanese taxonomic systems. To clarify the species boundaries of Melampsora species on willows in China, we tested two approaches for species delimitation inferred from morphological and molecular variations. Morphological species boundaries were determined based on numerical taxonomic analyses of morphological characteristics in the uredinial and telial stages by cluster analysis and one-way analysis of variance. Phylogenetic species boundaries were delineated based on the generalized mixed Yule-coalescent (GMYC) model analysis of the sequences of the internal transcribed spacer (ITS1 and ITS2) regions including the 5.8S and D1/D2 regions of the large nuclear subunit of the ribosomal RNA gene. Numerical taxonomic analyses of 14 morphological characteristics recognized in the uredinial-telial stages revealed 22 morphological species, whereas the GMYC results recovered 29 phylogenetic species. In total, 17 morphological species were in concordance with the phylogenetic species and 5 morphological species were in concordance with 12 phylogenetic species. Both the morphological and molecular data supported 14 morphological characteristics, including 5 newly recognized characteristics and 9 traditionally emphasized characteristics, as effective for the differentiation of Melampsora species on willows in China. Based on the concordance and discordance of the two species delimitation approaches, we concluded that integrative taxonomy by using both morphological and molecular variations was an effective approach for delimitating Melampsora species on willows in China.     

Molecular phylogeny,taxonomy, and distribution of French Unio species (Bivalvia,Unionidae)

A plethora of unionid names was established in the nineteenth century by the “Nouvelle Ecole”. Although naiad morphological plasticity is well documented, the currently recognized fauna, with 17 species and subspecies included in the French checklist for the Unio genus, is still based upon morphological characters only. Insights have been provided from molecular data elsewhere in Europe and North Africa, but the French fauna remains unstudied. We present a molecular phylogeny of the Unio genus in France based on COI, 16S and 28S genes; taking up all available data in Europe plus 273 specimens collected in all main French drainages. The results show that there are either three valid species in France, with U. pictorum and U. mancus synonymized, or five, with the subspecies U. crassus courtillieri elevated to species level. Subspecies were generally not recovered, which questions the evolutionary units tacitly implied by subspecific names. Although sampling topotypes is the most reliable way to evaluate the status of a nominal subspecies, major human-induced changes in aquatic hydrosystems challenge the method. Nevertheless, operational taxonomy has to rely on ground-truthed data and we propose to reduce the actual number of valid taxa in France to the seven observed operational taxonomic units.     

Gnaphalium teydeum and Gnaphalium luteo-album: two taxa of the Canary Islands with different genetic histories

Gnaphalium teydeum and G. luteo-album (Asteraceae) are two closely congeneric taxa native to the Canary Islands. While G. luteo-album is widespread in the Macaronesian Region, G. teydeum is endemic to the island of Tenerife and considered endangered by IUCN. Using the RAPD technique this study investigated the level and apportionment of genetic diversity of these taxa, trying to solve a taxonomic dispute related to G. teydeum. Based on the 102 DNA fragments generated by 11 primers, a high level of genetic differentiation was found between the taxa (F _ST  = 0.366), with G. luteo-album showing levels of genetic variability (P = 100%; H = 0.246) higher than those found in G. teydeum (P = 75.5%; H = 0.173). UPGMA dendrogram and Bayesian cluster analysis clearly separated populations from both the species. Overall, results show that although morphological differentiation between G. teydeum and G. luteo-album is not strong, they show marked molecular divergence, supporting the current taxonomic status.     

Taxonomic investigation using DNA fingerprinting in Geitlerinema species (Oscillatoriales, Cyanobacteria)

The taxonomic study of 14 strains of Geitlerinema amphibium (Ag. ex Gom.) Anagnostidis and Geitlerinema unigranulatum (R.N. Singh) Komárek and Azevedo, coming from several localities was undertaken. Use was made of morphological data and molecular data were obtained by means of the DNA fingerprinting technique using highly iterated palindrome (HIP1) sequences. The employed morphological characteristics were those used for species taxonomic identification belonging to the Geitlerinema genus, namely, cell dimensions, shape of the apical cell, motility, number and localization of cyanophycin granules in the cell. The two species revealed as polymorphic were discriminated only by means of the average cellular diameters. In spite of this, minima and maxima values of the cellular diameters overlapped. It was found from molecular analysis that a high genetic diversity and the formation of two clusters consisted of G. amphibium and G. unigranulatum, plus a sole strain keeping itself isolated from the remaining. Also, these clusters were not related to the geographic location; they encompassed strains from water bodies distant from each other by as much as 3500 km, or Brazilian and Spanish strains. Molecular and morphological data support the possibility that G. unigranulatum could be considered a synonym for G. amphibium. HIP1 fingerprinting is a powerful tool for the study of genetic of cyanobacteria closely related taxa. This study points to the necessity of using other than morphological data in the taxonomic revision of cyanobacteria, as well as in the proposition of new taxons.