Taxonomic Consequences Research Articles

Systematics of the extinct reed warblers Acrocephalus of the Society Islands of eastern Polynesia

In the Society archipelago (French Polynesia), Acrocephalus reed warblers are known only from four islands: Tahiti, Mo’orea, Huahine and Raiatea. All populations are now extinct except on Tahiti. Our knowledge of these birds is based on a small number of specimens preserved in museums, collected mostly during the 19th century. We present here a review of the past and present distribution, habitat and threats to the Society Islands reed warblers, including details on the specimens in museum collections. We compare the external morphology of the different populations, and use samples from museum specimens to propose a molecular phylogeny of all taxa based on partial cytochrome b gene sequences. The genetic data do not support the monophyly of the Society Islands reed warblers, which probably derived from three different lineages, found in Tahiti, Mo’orea and in the cluster Raiatea–Huahine. We outline the taxonomic consequences of this phylogeny. Our results support the hypothesis that evolutionary pattern, not distance between islands, shaped the long‐distance colonization of oceanic islands by reed warblers.

Phylogenetic analysis of the Triticeae (Poaceae)

A phylogenetic analysis, based on morphology, was made of the monogenomic genera of the Triticeae. Brachypodium P. B. and Bromus L. were used as outgroups. No less than 1335 equally parsimonious trees were found (length 113, consistency index 0.33). The consensus tree does not support the monophyly of the Triticeae. Two well defined clades were found, a Hordeum-clade and an /fegiYopj-clade. As the structure of the tree is only weakly supported, no taxonomic consequences are proposed.

Phylogenetic analysis of the Triticeae (Poaceae)

A phylogenetic analysis, based on morphology, was made of the monogenomic genera of the Triticeae. Bruchypodiurn P. B. and Bromus L. were used as outgroups. No less than 1335 equally parsimonious trees were found (length 113, consistency index 0.33). The consensus tree does not support the monophyly of the Triticeae. Two well defined clades were found, a Hordeurn-clade and an Aegilops-clade. As the structure of the tree is only weakly supported, no taxonomic consequences are proposed.

The systematics of Knoxieae (Rubiaceae)—molecular data and their taxonomic consequences

The tribe Knoxieae consists of genera formerly included in (at least) four tribes of the Rubiaceae (the coffee family). Apart from Knoxia itself, which is mainly Indomalesian, the group is from Africa and Madagascar. Most genera are herbaceous or shrubby, but small trees are also present. They generally have fimbriate, colleter‐tipped stipules and five‐merous flowers with unequal calyx lobes. We present a molecular phylogeny of the group (based on two chloroplast markers, rps16 and trnT‐F, and the nuclear ITS) and discuss the morphological support for the resulting groups and the taxonomic consequences of the phylogeny. Two hundred and sixty‐one new sequences from 90 species have been obtained. Of the 19 genera of the Knoxieae, all but three (two monotypic and one with two species) are represented. The genera Calanda, Chlorochorion, Neopentanisia, and Paraknoxia are merged with Pentanisia. Pentas is shown to be not monophyletic and is split into the new genera Phyllopentas, Dolichopentas, and Rhodopentas. We also suggest the Pentas subgenera Megapentas and Chamaepentadoides be included in Chamaepentas. The genus Carphalea is also shown to be not monophyletic and for the African members of the genus (section Dirichletia) the name Dirichletia should be used. Placopoda is suggested to be merged with Dirichletia. Triainolepis is enlarged to include Paratriaina and Thyridocalyx. The tribal position of Lathraeocarpa is discussed. Twenty‐nine new combinations for species and seven for infraspecific taxa are made. A key to the genera of Knoxieae is provided.

Structural elucidation of a novel phosphoglycolipid isolated from six species of Halomonas

The structure of a new phosphoglycolipid from the halophilic Gram-negative bacteria Halomonas elongata ATCC 33173(T), Halomonas eurihalina ATCC 49336(T), Halomonas almeriensis CECT 7050(T), strain Sharm (AM238662), Halomonas halophila DSM 4770(T), and Halomonas salina ATCC 49509(T) was elucidated by NMR and mass spectroscopy studies. In all of the species examined, the polar lipid composition consisted of 1,2-diacylglycero-3-phosphorylethanolamine, 1,2-diacylglycero-3-phosphoryl-glycerol, bisphosphatidyl glycerol, and the new phosphoglycolipid PGL1. The structure of PGL1 was established to be (2-(alpha-D-glucopyranosyloxy)-3-hydroxy-propyl)-phosphatidyl diacylglycerol. C16:0;C18:1 and C16:0;C19:cyclopropane are the most abundant acyl chains linked to the phosphatidylglycerol moiety of each isolated PGL1. All of the species presenting the lipid PGL1 belong to Halomonas rRNA group 1, suggesting that the new phosphoglycolipid could be a chemotaxonomic marker of this phylogenetic group.

Uniform phenotype conceals double colonization by reed‐warblers of a remote Pacific archipelago

AbstractAim Remote oceanic islands often provide good illustrations of adaptive radiations, but phylogenetic studies have also demonstrated unexpected multiple colonization events for a given archipelago. In this study we investigate the relationships among endemic populations of the Marquesas reed‐warbler, Acrocephalus mendanae Tristram, 1883, which have colonized nearly all islands of this remote Polynesian archipelago, and which exhibit a very uniform plumage pattern. We study the phylogeny and morphology of all subspecies in the Marquesas, providing an examination of the position of the Marquesas lineages in relation to reed‐warblers distributed across multiple Polynesian archipelagos.Location This study focused on all the main islands of the Marquesas archipelago, along with samples from other Polynesian archipelagos (Society, Tuamotu, Austral, Cook, Kiribati) and Australia.Methods We used mitochondrial DNA markers (cytochrome b and ND2 genes) to develop a phylogeny of the main eastern Polynesian taxa. All subspecies for the Marquesas were investigated, including multiple individuals per island. Phylogenetic analyses using maximum‐likelihood and Bayesian approaches were employed to infer relationships among A. mendanae populations and between the main Polynesian archipelagos. Morphometric analyses based on 110 specimens from museum collections were performed on external characters to investigate the differences between islands, and these results were compared to the phylogeny.Results Our data indicate that the Marquesas reed‐warbler is in fact a polyphyletic taxon including two independent lineages: the northern Marquesas reed‐warbler, closely related to the Tuamotu reed‐warbler, and the southern Marquesas reed‐warbler, sister taxon to that endemic to the Kiribati. Analyses of morphological characters show that the size and shape features of the Marquesas reed‐warblers exhibit high plasticity linked to adaptation to ecological factors, particularly habitat richness (the diversity of vegetation structure that provides suitable resources and habitat for reed‐warblers, simplified here as the number of indigenous plant species).Main conclusions Our results suggest that reed‐warblers have successfully colonized the Marquesas archipelago, one of the most remote groups of islands in the Pacific Ocean, at least twice. Both events occurred more or less simultaneously at ca. 0.6 Ma, and are more recent than the islands' formation. We outline the taxonomic consequences of our phylogeny and discuss the supertramp strategy of reed‐warblers in the Pacific.

Mitochondrial DNA variability in Giraffa camelopardalis: consequences for taxonomy, phylogeography and conservation of giraffes in West and central Africa

The giraffe ( Giraffa camelopardalis) still survives in four countries of West and central Africa. The populations of Niger and Cameroon are generally assigned to the subspecies peralta, but those of Chad and the Central African Republic are taxonomically problematic, as they are referred to as either peralta, or antiquorum, or congoensis. In this study, a mitochondrial fragment of 1765 nucleotide sites, covering the complete cytochrome b gene, three transfer RNAs and a large part of the control region, was sequenced to assess the relationships between several populations of giraffe. The phylogenetic analyses performed on the 12 identified haplotypes indicate that northern giraffes constitute a natural group, distinct from that of southern giraffes. Surprisingly, the giraffes of Niger are found to be more closely related to the giraffes of East Africa (subspecies rothschildi and reticulata) than to those of central Africa. We conclude therefore that the subspecies peralta contains only the Niger giraffes, whereas the subspecies antiquorum includes all populations living in Cameroon, Chad, the Central African Republic, and southwestern Sudan. We suggest that the ancestor of the Nigerian giraffe dispersed from East to North Africa during the Quaternary period and thereafter migrated to its current Sahelian distribution in West Africa, in response to the development of the Sahara desert. This hypothesis implies that Lake Mega-Chad acted as a strong geographical barrier during the Holocene, preventing any contact between the subspecies peralta and antiquorum. Our study has direct implications for conservation management, as we show that no subspecies peralta is represented in any European zoos, only in Niger, with a small population of less than 200 individuals. To cite this article: A. Hassanin et al., C. R. Biologies 330 (2007).

Reconstructing the Clavariaceae using nuclear large subunit rDNA sequences and a new genus segregated from Clavaria

Fungi that produce clavarioid fruit bodies have evolved independently many times in the Basidiomycota. The evolutionary significance of this morphology is difficult to interpret because the phylogenetic positions of many clavarioid fungi are still unknown. In this study we examined the phylogenetic diversity of the Clavariaceae sensu lato among Homobasidiomycetidae by adding partial nuclear large subunit ribosomal DNA sequences from clavarioid and corticioid fungi to a large euagaric dataset and analyzing them both together and separately. Our results indicate that the clavarioid morphology has evolved at least five times in the euagarics while the inclusion of type species enabled us to evaluate the taxonomic consequences of this polyphyletic distribution. Although the sampling available at present is incomplete, a qualitative assessment of our phylogenetic hypotheses indicates that the clavarioid habit might not be as evolutionary labile as previously reported. We propose the new genus Alloclavaria to accommodate Clavaria purpurea, which is not related to Clavaria but is derived within the hymenochaetoid clade. The Physalacriaceae and Clavariaceae are redefined to reflect monophyletic groups, and the limits of Clavaria, Clavulinopsis and Ramariopsis should be reconsidered when additional data are available.

Reconstructing the Clavariaceae using nuclear large subunit rDNA sequences and a new genus segregated from Clavaria

Fungi that produce clavarioid fruit bodies have evolved independently many times in the Basidiomycota. The evolutionary significance of this morphology is difficult to interpret because the phylogenetic positions of many clavarioid fungi are still unknown. In this study we examined the phylogenetic diversity of the Clavariaceae sensu lato among Homobasidiomycetidae by adding partial nuclear large subunit ribosomal DNA sequences from clavarioid and corticioid fungi to a large euagaric dataset and analyzing them both together and separately. Our results indicate that the clavarioid morphology has evolved at least five times in the euagarics while the inclusion of type species enabled us to evaluate the taxonomic consequences of this polyphyletic distribution. Although the sampling available at present is incomplete, a qualitative assessment of our phylogenetic hypotheses indicates that the clavarioid habit might not be as evolutionary labile as previously reported. We propose the new genus Alloclavaria to accommodate Clavaria purpurea, which is not related to Clavaria but is derived within the hymenochaetoid clade. The Physalacriaceae and Clavariaceae are redefined to reflect monophyletic groups, and the limits of Clavaria, Clavulinopsis and Ramariopsis should be reconsidered when additional data are available.

Radiation of Atlantic goldcrests Regulus regulus spp.: evidence of a new taxon from the Canary Islands

Phylogenetic relationships between goldcrest populations from the Atlantic Islands (Azores and Canary Islands) were investigated by two molecular markers (mitochondrial control region and cytochrome b sequences), and partly by morphology and territorial song. The Azorean goldcrest populations are closely related to European nominate R. r. regulus. Most probably, the Azores were colonized by goldcrests in a single late‐pleistocene invasion, while colonization of the Canary Islands presumably occurred in two steps: An early invasion to Tenerife and La Gomera 1.9–2.3 million years (my) ago and a more recent one to El Hierro and La Palma 1.3–1.8 my ago. Distribution of haplotypes on the Azores suggests a division of R. r. azoricus on São Miguel into an eastern population with close affinities to R. r. sanctaemariae and a western population belonging to the lineage of R. r. inermis on the central and western island group. The Canarian populations are genetically substructured into a northeastern group embracing Tenerife and La Gomera and a second, southwestern group including El Hierro and La Palma. Genetic distances between members of the two Canarian clades range at 3.1–3.4% (TrN distance, control region and cytochrome b). Differentiation between the two groups is also supported by morphology and by territorial song. Substitution rate estimates for the both genes range at approximately the same values of 0.0031 and 0.0044 substitutions per site and lineage per my which roughly corresponds 0.61–0.83% divergence between Regulus lineages per my. Highest local rates occur in island clades of the Azorean and the Canarian population and in R. r. japonensis from the Russian Far East and Japan. However, a general acceleration of a molecular clock in island populations is not evident from the Regulus data set due to extremely low local rate estimates in the Canarian clade of Tenerife and La Gomera. As a taxonomic consequence of the marked differentiation of the two Canarian goldcrest clades the populations from El Hierro and La Palma are described as a taxon new to science and are named Regulus regulus ellenthalerae n. ssp.

Revision of the pentacrinid stalked crinoids of the genus Endoxocrinus (Echinodermata, Crinoidea), with a study of environmental control of characters and its consequences for taxonomy

A revision of the stalked crinoid species attributed to the genus Endoxocrinus A.H. Clark, 1908 (Diplocrininae, Pentacrinitidae, Crinoidea, Echinodermata) is conducted using studies on phenotype variation and its relation with environment. Specimens collected via submersible at five sites in the Bahamas exhibit distinct phenotypes that correlate with different apparent ecological niches and serve as references for interpreting specimens dredged in Atlantic and Pacific Oceans where detailed information on their benthic environment is unknown. Documentation of ecophenotypic convergences or divergences allows us to distinguish between adaptive characters and those revealing genetic affinities, and to discuss allopatric evolution and bathymetric zonation. The results suggest the following taxonomy: the genus Endoxocrinus is subdivided into two subgenera, i.e., Endoxocrinus A.H. Clark, 1908 and Diplocrinus Döderlein, 1912 (Annacrinus A. H. Clark, 1923 becomes a junior synonym of Diplocrinus); the subgenus Endoxocrinus is monospecific with E. (E.) parrae [Gervais (in Guérin, 1835)] from the western tropical Atlantic; the subgenus Diplocrinus includes E. (D.) alternicirrus (Carpenter, 1882) from the western and central Pacific, E. (D.) maclearanus (Thomson, 1872) from the western tropical Atlantic, and E. (D.) wyvillethomsoni (Jeffreys, 1870) from the northeastern Atlantic. Endoxocrinus (E.) parrae includes three subspecies adapted to different habitats and depths: E. (E.) parrae parrae usually in 154–518 m with moderate to high current velocity and moderate turbulence to laminar flow, E. (E.) parrae carolinae (A.H. Clark, 1934) in 504–724 m with moderate current velocity and high turbulence, and E. (E.) parrae prionodes H.L. Clark, 1941 in 402–832 m with high current velocity in laminar flow. E. (D.) alternicirrus includes two subspecies, E. (D.) alternicirrus alternicirrus in 625–1476 m and E. (D.) alternicirrus sibogae (Döderlein, 1907) usually in 364–800 m. E. (D.) maclearanus has a depth range of 432–878 m and occurs as a dwarf variety minimus n. var. in high current velocities and high turbulence. E. (D.) wyvillethomsoni from depths of 1214–2070 m lives on various substrates under a variety of hydrodynamic conditions.

Taxonomic consequences from the combined molecular and phenotype evaluation of selected Anabaena and Aphanizomenon strains

Taxonomic consequences from the combined molecular and phenotype evaluation of selected Anabaena and Aphanizomenon strains

The great tit (Parus major) - a misclassified ring species

The great tit (Parus major) has been considered to be the most typical example of an avian ring species. The terminal taxa of the ring (major and minor sectors) are supposed to be reproductively isolated in a zone of secondary contact in the middle Amur valley, Siberia. Our study combines molecular markers (cytochrome-b), bioacoustic analyses and morphological characters to judge the ring species status of the great tit complex. Despite a notable percentage of intermediately coloured birds in the mixed population of middle Amur, a lack of mitochondrial introgression between the major and minor sectors and a small number of true hybrids among voucher specimens from this area suggest at least a partial reproductive barrier between both sectors. In contrast, variation of morphological and especially acoustic characters along the ring-shaped area and the phylogenetic structure of the P. major group do not match the ring species concept. Bioacoustic and molecular data (cytochrome-b sequences) reveal two large and closely related subspecies blocks, the sectors major and bokharensis in the Western Palaearctic and central Asia, and the sectors minor and cinereus in the Eastern Palaearctic and South-east Asia, respectively. The two western sectors diverged only recently (0.5 Mya) and they were separated from the eastern group by Pleistocene events about 1.5 Mya. Songs from allopatric regions of the two subspecies blocks differ distinctly in frequency parameters and element composition. In the area of secondary contact, males of all phenotypes share the same frequency range of song, close to the range of the typical minor song. Hybrids and major males sing mixed repertoires of typical major and minor strophe types as well as mixed strophes. In contrast, phenotypic minor males display only pure minor strophes. Differences in mate choice and mating success based on repertoire size are believed to uphold the reproductive barrier between major and minor birds in the area of sympatry. Taxonomic consequences suggest three separate species in the Parus major complex: Parus major s.s. (including the very closely related bokharensis sector), Parus minor and Parus cinereus. © 2005 The Linnean Society of London, Biological Journal of the Linnean Society, 2005, 86, 153–174.

Galerina Earle: A polyphyletic genus in the consortium of dark-spored agarics

The basidiomycete genus Galerina Earle accommodates more than 300 small brown-spored agarics worldwide, predominantly described from the Northern hemisphere. The delimitation of species and infrageneric units hitherto has been based on morphological and, to some extent, ecological characters. In this study we have analyzed nuclear ribosomal LSU and ITS sequences to reveal infrageneric phylogeny and the phylogenetic placement of Galerina among the dark-spored agarics. Sequences from 36 northern hemisphere Galerina species and 19 other dark-spored taxa were analyzed, some of them obtained from EMBL/GenBank. Our results, received from Bayesian and distance methods, strongly suggest that Galerina is a polyphyletic genus. The LSU analysis shows that Galerina is composed of three or four separate monophyletic main groups. In addition, a few species cluster together with other dark-spored agarics. The same groups are recognized in the ITS tree and they correspond roughly to previously recognized subgenera or sections in Galerina. With high support our LSU analysis suggests that Gymnopilus is a monophyletic genus and that Gymnopilus and one of the Galerina lineages (“mycenopsis”) are sister groups. The analyses further indicate that the Galerina lineages, as well as the genus Gymnopilus, could be referred to a strongly emendated family Strophariaceae, which corresponds largely to the family as circumscribed by Kühner (1980). Our results affirm that morphological characters often are highly homoplastic in the agarics. At the present stage formal taxonomic consequences or nomenclatural changes are not proposed.

Galerina Earle: A polyphyletic genus in the consortium of dark-spored agarics

The basidiomycete genus Galerina Earle accommodates more than 300 small brown-spored agarics worldwide, predominantly described from the Northern hemisphere. The delimitation of species and infrageneric units hitherto has been based on morphological and, to some extent, ecological characters. In this study we have analyzed nuclear ribosomal LSU and ITS sequences to reveal infrageneric phylogeny and the phylogenetic placement of Galerina among the dark-spored agarics. Sequences from 36 northern hemisphere Galerina species and 19 other dark-spored taxa were analyzed, some of them obtained from EMBL/GenBank. Our results, received from Bayesian and distance methods, strongly suggest that Galerina is a polyphyletic genus. The LSU analysis shows that Galerina is composed of three or four separate monophyletic main groups. In addition, a few species cluster together with other dark-spored agarics. The same groups are recognized in the ITS tree and they correspond roughly to previously recognized subgenera or sections in Galerina. With high support our LSU analysis suggests that Gymnopilus is a monophyletic genus and that Gymnopilus and one of the Galerina lineages ("mycenopsis") are sister groups. The analyses further indicate that the Galerina lineages, as well as the genus Gymnopilus, could be referred to a strongly emendated family Strophariaceae, which corresponds largely to the family as circumscribed by Kühner (1980). Our results affirm that morphological characters often are highly homoplastic in the agarics. At the present stage formal taxonomic consequences or nomenclatural changes are not proposed.

Species or subspecies? The dilemma of taxonomic ranking of some South-East Asian hawk-eagles (genus Spizaetus)

A molecular phylogeny of the Spizaetus cirrhatus complex is presented in this study, based on two sections of the mitochondrial genome: partial sequences of the cytochrome b gene and of the control region (CR). The topologies derived from the two sequences are in agreement. Within S. cirrhatus distances are rather low (0–1.5% in cytochrome b). Among the cirrhatus subspecies the island taxa floris, vanheurni and andamanensis form distinct haplogroups in the CR trees, conforming to the earlier subspecific divisions which were based on morphological characters. On the other hand, the most widespread subspecies, limnaeetus, does not represent a monophyletic group in the gene trees and its haplogroups do not cluster according to geographic affinities. An unambiguous resolution of relationships among haplotypes and haplogroups, respectively, was not achieved, suggesting a more recent radiation of this group of hawk-eagles in the course of the last ice ages. Concerning the outgroup taxa Spizaetus philippensis and Spizaetus lanceolatus, our data indicate a clear genetic distinction between the two subspecies S. p. philippensis and S. p. pinskeri, suggesting that they should be treated as distinct species. Yet the phylogenetic relationships of the three outgroup taxa with respect to S. cirrhatus are ambiguous in our trees. The taxonomic consequences of applying different species concepts (BSC, PSC) are discussed. The species concept chosen would result in different conservation strategies.

Nomenclature and taxonomy of the genus Salmonella

The nomenclature of the genus Salmonella has reached an unsatisfactory state of affairs, with two systems of nomenclature in circulation. One system, proposed in the 1980s by Le Minor and Popoff, has received wide acceptance, although it does not conform to the rules of the Bacteriological Code. The other system, which conforms to the rules of the Bacteriological Code, is being used by an ever-decreasing minority. As a result of a number of recent Requests for an Opinion, the Judicial Commission of the International Committee on the Systematics of Prokaryotes has issued an Opinion (Opinion 80) with the intention that it should solve these discrepancies. However, like all Opinions, it is limited to matters of nomenclature and does not help to interpret the taxonomic consequences. The Judicial Commission has therefore asked experts in the field of nomenclature and taxonomy to write a commentary on the nomenclatural and taxonomic consequences of Opinion 80. The present article explains the nomenclatural consequences of Opinion 80, together with a clear presentation of the taxonomy that results when applying the currently widely accepted interpretation that the genus Salmonella currently includes only two species.

A re-evaluation of morphological characters in European Gentianella section Gentianella (Gentianaceae)

Morphological traits were investigated in Gentianella section Gentianella by morphometrics and Scanning Electronic Microscopy (SEM). Variation in vegetative measures and in calyx, corolla, ovary, and gynophor was analyzed in populational samples and herbarium material. Special emphasis was given to micro-morphology and variation of papillae on the calyx using SEM. Three types of papillae on the calyx lobes were found: (A) short conical (G. amarella-group, G. insubrica, G. germanica); (B) long conical often curved (G. campestris, G. anisodonta, G. engadinsesis, and G. liburnica; (C) long cylindrical (G. aspera and G. pilosa). G. austriaca, G. caucasea,G. crispata, G. fatrae, and G. ramosa usually lack any papillae. Plants without and with short conical papillae were found in G. bulgarica and G. lutescens as well as in the intermediate taxa G. bohemica and G. stiriaca. The different types of papillae together with other calyx characters (sinus, shape and margin of lobe) are of high systematic importance and provide more stable characters than morphometric flower measures. Principal component and correlation analysis revealed a strong response of nearly all morphometric traits to the environmental variable altitude. Adaptive and historical causes of morphological variation as well as taxonomical consequences are discussed and a determination key is provided.

Genetic vs. morphological differentiation of Old World buzzards (genus Buteo, Accipitridae)

Kruckenhauser, L., Haring, E., Pinsker, W., Riesing, M. J., Winkler, H., Wink, M. & Gamauf, A. (2004). Genetic vs. morphological differentiation of Old World buzzards (genus Buteo, Accipitridae). — Zoologica Scripta, 33, 197–211.Here, a comprehensive phylogenetic investigation of Old World buzzards of the buteo–vulpinus complex and related taxa using morphological and genetic markers is presented. The morphometric analysis proved useful to discriminate taxa. Nevertheless, phylogenetic relationships cannot be resolved with these characters. Sequence comparisons between the control region and the pseudo‐control region revealed that the latter is the most variable section of the mitochondrial genome. Consequently it was used as a marker sequence. In the genetic analysis, almost no sequence variability was found among taxa comprising the buteo–vulpinus complex as well as Buteo rufinus and Buteo oreophilus, suggesting gene flow and/or incomplete lineage sorting. Thus, rapid morphological differentiation in adaptation to different environments was not accompanied by genetic differentiation of the mitochondrial genomes of these taxa. In contrast, the East Palearctic taxa are well differentiated genetically. The ‘superspecies’ concept and taxonomic consequences of our results are discussed.

Contribution à la connaissance des Odonates de Guyane française. Les larves de Macrothemispumila Karsch, 1889 et de Brechmorhoga praedatrix Calvert, 1909. Notes biologiques et conséquences taxonomiques (Anisoptera: Libellulidae)

Résumé Les larves de Macrothemis pumila Karsch, 1889 et de Brechmorhoga praedatrix Calvert, 1909 sont décrites et illustrées pour la première fois. La larve de M. pumila est très différente des autres larves connues du genre et nombre de ses caractères échappent à la diagnose générique telle qu’énoncée par Ramirez & Novelo-Gutiérrez (1999). Son statut au sein du genre est discuté. La larve de B. praedatrix se distingue des autres larves connues du genre, entre autres par des épines dorsales très prononcées et aiguës sur les segments abdominaux 2 à 9. Elle semble inféodée à une plante des sauts, Mourera fluviatil is Aublet, 1775.