Dominique Pluot-Sigwalt

Révision des Amblytylus et essai de mise au point sur les genres Amblytylus Fieber et Megalocoleus Reuter (Heteroptera: Miridae: Phylinae)

Résumé Les vingt-deux espèces actuellement répertoriées dans le genre paléarctique Amblytylus Fieber ont été examinées. Le genre est redéfini principalement d’après les caractères des genitalia mâles. Dix espèces sont maintenues dans le genre: A. albidus (Hahn 1834), A. amoenus Wagner 1958, A. arnoldiorum Kerzhner 1977, A. brevicollis Fieber 1858, A. concolor Jakovlev 1877, A. crassicornis Wagner 1964, A. jani Fieber 1858, A. montanus Wagner 1974, A. nasutus (Kirschbaum 1856), A. peitho Linnavuori 1997; toutefois, A. amoenus est considérée comme incertae sedis et A. jani comme nomen dubium. Deux espèces sont transférées dans le genre Megalocoleus Reuter: Megalocoleus delicatus (Perris 1857) n. comb., Megalocoleus tarsalis (Reuter 1894) n. comb. Dix espèces sont mises en synonymie; soit avec une espèce d’Amblytylus: A. similis Wagner 1971 n. syn. de A. albidus (Hahn 1834); A. gregarius Linnavuori 1961 n. syn. de A. brevicollis Fieber 1868; A. vittiger Reuter 1899 n. syn., A. longicornis Wagner 1953 n. syn. et A. eckerleini Wagner 1964 n. syn. de A. concolor Jakovlev 1877; soit avec une espèce de Megalocoleus: A. erectus Wagner 1971 n. syn. de M. longirostris (Fieber 1861); A. glaucicollis Kerzhner 1977 n. syn. de M. exanguis (Herrich-Schaeffer 1835); A. macedonicus Wagner 1956 n. syn. de M. naso (Reuter 1879) n. comb.; A. luridus Hoberlandt 1961 n. syn. et A. scutellaris Horvath 1905 n. syn. de M. delicatus (Perris 1857) n. comb. Un lectotype est désigné pour quatre espèces (Lopus nasutus Kirshbaum, Amblytylus vanduzeei Blatchey, Amblytylus scutellaris Horváth, Capsus delicatus Perris). Une clé d’identification pratique bilingue (français et anglais) basée surtout sur des caractères externes tente de séparer les espèces d’Amblytylus. Une clé révisée des espèces de Megalocoleus est également fournie. Les deux genres Amblytylus et Megalocoleus, très semblables par l’habitus, restent difficiles à définir. Seules les plantes-hôtes - des Poaceae chez les Amblytylus, des Asteraceae chez les Megalocoleus - et dans une moindre mesure la vesica pourvue de deux processus apicaux (Amblytylus) ou d’un seul (Megalocoleus) semble indiquer l’existence de deux groupes d’espèces distincts.

Molecular Species Delimitation and Morphology of Aquatic and Sub-Aquatic Bugs (Heteroptera) in Cameroon

Aquatic and semi-aquatic bugs (Heteroptera) represent a remarkable diversity and a resurging interest has been given to documenting at the species level these insects inhabiting Cameroon in Central Africa due to their potential implication in the transmission of the bacterium Mycobacterium ulcerans, the causal agent of Buruli ulcer, an emerging human disease. A survey was carried out over two years in Cameroon. Morphological analyses were done in two steps. A first step consisted in separating the specimens based on broadly shared characters into morphotypes. The specimens were then separated into two independent batches containing each the same representation of each morphotype. One batch (309 specimens) was used by taxonomy experts on aquatic bugs for species level identification and/or to reconcile nymph with their corresponding adult species. The second batch (188 specimens) was used to define species based on the COI DNA sequences (standard sequence used for “DNA barcoding”) and using the Automatic Barcode Gap Discovery (ABGD) method. The first morphological analysis step separated the specimens into 63 different morphotypes (49 adults and 14 nymphs), which were then found to belong to 54 morphological species in the infra-orders Gerromorpha and Nepomorpha based on the species-level morphological identification, and 41–45 putative molecular species according to the gap value retained in the ABGD. Integrating morphology and “DNA barcoding” reconciled all the specimens into 62 aquatic bug species in Cameroon. Generally, we obtained a good congruence between species a priori identified based on morphology from adult morphotypes and molecular putative species. Moreover, molecular identification has allowed the association of 86% of nymphs with adults. This work illustrates the importance of integrative taxonomy.

Notes sur Micrauchenus lineola (Fabricius 1787), espèce termitophile et termitophage (Heteroptera: Reduviidae: Harpactorinae, Apiomerini)

Résumé Contrairement aux autres Apiomerini, des prédateurs souvent polyphages vivant sur des plantes diverses, Micrauchenus lineola semble se nourrir exclusivement de termites. Des immatures à différents stades ont été trouvés dans les galeries d’une termitière (Nasutitermes sp.) où ils sont apparemment bien acceptés par les termites dont ils se nourrissent. Quelques particularités morphologiques sont précisées chez l’adulte: - tête courte et convexe, - stylet maxillaire droit pourvu de longs processus lamelliformes, - absence de sillon tarsal sur les pattes antérieures. Le stylet maxillaire droit montre des similitudes avec ceux d’autres Reduviidae termitophages appartenant aux Salyavatinae et aux Sphaerodopinae.

Checklist, distribution, and a new record of Nepomorphan water bugs (Hemiptera: Heteroptera) in northern Tunisia

We report on the results of a survey of the Nepomorpha of northern Tunisia, and list twenty-three species belonging to twelve genera and seven families: Nepidae, Ochteridae, Corixidae, Micronectidae, Naucoridae, Notonectidae, and Pleidae. These records are based on intensive field surveys during the year 2013 and examination of the entomological collections of the National Museum Natural History of Paris. Ranatra linearis (Linnaeus, 1758) is recorded for the first time from Tunisia. The occurrence of Sigara (Halicorixa) stagnalis stagnalis (Leach, 1817) in Tunisia is confirmed. A preliminary checklist of the Nepomorpha of Northern Tunisia and updated distribution maps for all species treated are provided for further studies.

Convergent Reduction of Ovariole Number Associated with Subterranean Life in Beetles.

Background Some species of obligate cavernicolous beetles are known to possess a unique feature—a contraction of the larval cycle. In contrast to many other subterranean beetles, life-cycle contraction in Trechini ground beetles (Carabidae) is correlated with a reduction in the number of eggs and a drastic reduction in the number of ovarioles. This remarkable peculiarity has only been reported for a small number of closely related species. Results We give a description of the female internal reproductive system for six species of Trechini, including five subterranean species, with a particular focus on the western Pyrenean radiation of Aphaenops, a group for which nothing is known regarding the early life stages. We redescribe the internal female genitalia of A. crypticola Linder. Study of the ovarioles allowed us to infer the postembryonic development of the larvae for each species examined. We then used a phylogenetic framework to recognize two independent reductions in the number of ovarioles in the Pyrenean lineage. We discuss the multiple convergent evolutions in ovariole number and the potential link between a reduction of ovariole number and troglobiomorphism in a phylogenetic context. Conclusions There is an extreme reduction in ovariole number and size within the species studied; the eggs produced by small ovarioles have a remarkably large size. A reduction to one ovariole has occurred independently at least twice in this subterranean group. A reduction in the number of ovarioles in ground beetles is one of the striking consequences of subterranean specialization and it is correlated with another remarkable adaptation of subterranean beetles, a reduction in the number of larval instars.

Ecology and Feeding Habits Drive Infection of Water Bugs with Mycobacterium ulcerans

AbstractMycobacterium ulcerans (MU), the causative agent of Buruli ulcer, is present in a wide spectrum of environments, including terrestrial and aquatic ecosystems in tropical regions. The most promising studies on the epidemiological risk of this disease suggest that some ecological settings may favor infection of animals with MU including human. A species’ needs and impacts on resources and the environment, i.e., its ecological niche, may influence its susceptibility to be infected by this microbial form. For example, some Naucoridae may dive in fresh waters to prey upon infected animals and thus may get infected with MU. However, these studies have rarely considered that inference on the ecological settings favoring infection and transmission may be confounded because host carrier sister species have similar ecological niches, and potentially the same host–microbe interactions. Hence, a relationship between the ecological niche of Naucoridae and its infection with MU may be due to a symbiotic relationship between the host and the pathogen, rather than its ecological niche. To account for this confounding effect, we investigated the relationships between surrogates of the ecological niche of water bug species and their susceptibility to MU, by performing phylogenetic comparative analyses on a large dataset of 11 families of water bugs collected in 10 different sites across Cameroon, central Africa. Our results indicate that MU circulates and infects a couple of host taxa, i.e., Belostomatidae, Naucoridae, living both in the aquatic vegetation and as predators inside the trophic network and sister species of water bugs have indeed similar host–microbe interactions with MU.

Halyomorpha halys (Stål 1855) en Île de France (Hemiptera : Pentatomidae : Pentatominae) : surveillons la punaise diabolique

Résumé Le Pentatomidae (Insecta : Hemiptera) d’origine asiatique Halyomorpha halys (Stal 1855) a été trouvée en Ile de France (Paris intra muros et Lardy, Essonne) à la fin de l’année 2013. Ces occurrences font suite à celle de l’été 2013 dans l’agglomération de Strasbourg, près de la frontière allemande. Il s’agit de la 5e mention de cette espèce en Europe après la Suisse, l’Allemagne, et l’Italie. Il serait nécessaire de surveiller l’expansion de cette espèce polyphage et dommageable à des nombreuses cultures, dont l’expansion en Europe est très rapide, et qui peut être un agent allergénique.

An investigation of the roof of the genital chamber in female plant-bugs with special emphasis on the “dorsal sac” (Hemiptera: Heteroptera: Miridae)

Summary In Miridae, the roof (dorsal wall) of the female genital chamber (bursa copulatrix) is often neglected in taxonomic studies, rarely represented in its entirety and its importance is usually underestimated. It contains several organs that are relevant for taxonomy and phylogeny, namely the ringed glands (parieto-vaginal glands) encircled by the widely used sclerotized rings, the spermathecal gland (vermiform gland), and the lateral oviducts; it may also display various “dorsal sacs” or pouches and other poorly known structures. The comparison of 24 species belonging to seven mirid subfamilies, and various additional literature data, suggest that the general architecture of the roof and the topographic relations of its different organs may be used to ascertain relationships of higher taxa. Information is mainly provided on the “dorsal sac”, i.e. a very variable pouch-like structure usually medially located in the vicinity of the lateral oviducts and the spermathecal gland. The dorsal sac is derived from the roof of the genital chamber, i.e. is a differentiation of the vaginal wall, and cannot be derived from the common oviduct as claimed by several authors. Apparently, the common oviduct does not exist in Miridae. A dorsal sac, variously shaped, occurs within most subfamilies examined (Cylapinae, Orthotylinae, Phylinae, Bryocorinae, Deraeocorinae, Mirinae). Some representatives of the tribe Mirini and Stenodemini (Mirinae) exhibit two types of dorsal sac. The subfamily Isometopinae as well as some species in each of the other subfamilies examined seem to be devoid of dorsal sac. Apparently, dorsal sacs are adaptive pouches which receive and lodge some parts of the phallus during copulation. At species level, the dorsal sac is informative in providing diagnostic characters. At supraspecific levels (genus, tribe, subfamily) the dorsal sac must be examined jointly with other equally informative structures of the roof: architecture of the sclerotized rings; location of the spermathecal gland; location, length and aspect of the lateral oviducts; aspect and size of the infoldings of the lateral margins of the genital chamber (mainly in Phylinae and Orthotylinae); shape of the genital chamber in dorsal view; and the presence, aspect and size of the paired lateral apodemes of the genital chamber.

Giant-sized chromosomes in genus Phyllobrotica Chevrolat 1837 (Coleoptera: Chrysomelidae: Galerucinae) and parthenogenesis in P. adusta (Creutzer 1799)

Summary Only females were detected in a small population of Phyllobrotica adusta (Creutzer 1799) (Chrysomelidae: Galerucinae) located in a mountain near Kastoria (Greece). Their karyotype, composed of 42 chromosomes, including three giant-sized ones, is assumed to be triploid. Only two giant-sized chromosomes were present in the 37,X/38,XX karyotype of the congeneric sexual species P. quadrimaculata (L. 1758). Although males were described in P. adusta, the abnormal sex ratio, the presumed triploidy and the absence of spermatozoa in the spermatheca strongly suggest a parthenogenetic reproduction of the population studied. Both parthenogenesis and giant-sized chromosomes have been described independently in some species of Neotropical and Palearctic Galerucinae, but never together.