VISIOCONFÉRENCE ORSAY, 15 septembre 2014 INFLUENCE DU CHANGEMENT CLIMATIQUE SUR LA DISTRIBUTION DES ESPÈCES VENIMEUSES M. Goyffon, MNHN, Paris, [email protected] PROLIFERATIONS SEASONAL OCCASIONAL INVASIVE SPECIES 1) SEASONAL PROLIFERATIONS ARTHROPODS Urticant (sting) (Lepidoptera) Vesicant (contact) (Coleoptera) LEPIDOPTERA LEPIDOPTERISM / ERUCISM (urticant) LEPIDOPTERISM (adults) - Less frequent than erucism (larvæ) -Main families : -Saturniidæ : Hemileucinæ : Lonomia, Hylesia, South America -Thaumetopoeidæ : Anaphe, Africa ; Thaumetopoea, Eur., Euproctis, Asia - Lymantriidæ : L. dispar, Eur., North Am. ERUCISM (larvæ) - frequent, -17 families, about 140 genera, Heterocera & some Rhopalocera, -Main families : -Saturniidæ, Hemileucinæ : Hylesia, Lonomia, South America ; -Notodontidæ : Thaumetopoea, Europe ; Anaphe, Africa -Lasiocampidæ : Dendrolimus, Asia ; Streblote, Europe - Nymphalidæ : Morpho sp. Hylesia sp. (Sth Amer.) Anaphe sp. (Africa) Lonomia sp. (Brazil) Thaumetopoea sp. - Main species in Europa : T. processionæ, T. pityocampa - Among urticant Lepidoptera, only these species seem in a phase of territorial expansion [one cycle per annum], - Nuisances concerning also animals (dogs, cats, cattle) Thaumetopoea pityocampa Thaumetopoea pityocampa STAPHYLINIDÆ (vesicant) STAPHYLINIDÆ (rove beetles) Characteristics - Vesicant insects, ubiquitous (> 600 sp.) - Main genus : Pæderus, toxin known - Contact dermatitis known at least at the beginning of the XXth century - Attracted on evening by light in houses, even in winter in the Mediterranean basin - Maybe important increasing frequency of accidents due to a climate change PÉDÉRINE - Produced by an endosymbiotic bacteria, genus Pseudomonas, - Chemical synthesis realized, - Principally in females, - Dead insects “active”, - Hand palms insensitive to rinse, - Insects attracted by electric lights. SYMPTOMATOLOGY - One or several erythema (then systemic signs possible), - Appearing after one or several insects crushed on skin, - Transport of toxins by hand palms possible, - Three grades : benign, moderate, severe (rarely) with systemic symptoms, - Secondary infection possible OTHER SPECIES (expansions) Snakes -Vipera aspis, H. viridiflavus (Europa, latitude) - Crotalus atrox which replaces C. molossus (North America, USA, altitude) Hierophis viridiflavus (non venomous) Whip snake H.v. Crotalus atrox Crotalus molossus Crotalus molossus 2) OCCASIONAL PROLIFERATIONS (not dependent of season) - Cnidae (venomous) - Iuliforms (millipedes, vesicant) CNIDAE : JELLYFISH P. noctiluca [Sea nettle] Physalia grounded on a beach (France) Physalia grounded on a beach (France) SYMPTOMS, TREATMENT - Contacts painful, marks of contact often persistent, - Avoid rubbings, - Take off the fragments of tentacles (if any) with small tongs, - Analgesic drugs. IULIFORMS - Diplopods : not venomous (as Chilopods, for example), but “vesicant” as some insects. Ex. : Ommatoiolus sp. - Possible huge proliferations in some countries, causes not well known, - Nuisance rather than a health problem. Anthropic environments (I) Possibility for some venomous species to adapt to various anthropic environments : two examples of snakes (adaptation limited in time and space) Causus sp. Causus maculatus (Africa) - in banana plantations, especially if strawed ground which retains moisture, - Causus maculatus is an African viper which causes severe non-fatal envenomings. Echis ocellatus ECHIS OCELLATUS - Echis ocellatus is a dangerous African viper - It is a consumer of venomous Chilopods (Scolopendra sp.) which are themselves consumers of small arthropods in rubbish piles neglected, during the rain-season. So, serious “domestic” envenomings may appear during this season in some countries of Black Africa. URBAN SCORPIONISM Benign (France) or dangerous (America : Brazil, Argentina, USA) Characteristics (in tropical regions) : - Parthenogenesis (Tityus sp.), - Opportunistic food : cockroaches, - Ecological adaptability, - Currently : only America (N. and S.) Euscorpius flavicaudis (harmless) Adaptation to anthropic environments : urban scorpionism Tityus serrulatus : Brazil (Brasilia) Tityus trivittatus : Argentina (Buenos Aires) Centruroides sculpturatus (Los Angeles, USA), generally in gardens, not inside Common characteristics : parthenogenesis (only Tityus sp.) Main food : cockroaches, various insects Tityus serrulatus (Brazil) Tityus trivitattus (Argentina) Centruroides sp. INVASIVE SPECIES - Hymenoptera (stinging), - Vertebrates : amphibia, snakes, fish (lionfish) - Hornets - Bees - Ants Vespa crabro European hornet Vespa velutina Asian hornet Map in 2012 VESPA VELUTINA - Hornet Vespa velutina came probably from China (marine transport), - Rapid invasion of France up to Belgium, - Predator of bees, - Less diurnal than V. crabro, - Some deaths registered in France, even if its venom seems without particularities. Apis sp. Invasive bees - Brazilian hybrids produced 50 yrs ago : Apis mellifera ligustica x A. m. adansoni - Hybrids better adapted to the tropical climate, but more aggressive (“killer bees”) - Invasion of the South America, then Central America, and North America up to Texas and Arizona. Many multiple stings recorded. - No particularities in the composition of hybrid venoms. BEHAVIOR OF THE HYBRID BEES (“killer bees”) - They collect pollens whatever the weather, even if clouds, - In tropical regions, bees are active during the year, not only in Spring-Summer. - When a human is too near the hives, he is attacked on 500 m or more (more than the 50-100 m for A. mellifera mellifera), with multiple stings. A.mellifera : swarm INVASIVE ANTS I (7-8 sp.) Commune characteristics : - Polygyny (several queens), unicoloniality (several nests, one colony), - Mating in the nest, - Omnivora, - High aggressiveness, - Rapid mobilization of the populations, - Sudden population explosions, - Not all species venomous. INVASIVE ANTS (II) - Not (or very rarely) a medical problem, but : - Ecological problems, as a nuisance for the natural populations (arthropods, microvertebrates, plants) which are eliminated by the invasive ants. - Also : many damages in houses (electric wire, plastic things). Argentine ant Linepithema humile Yellow foolish ant Anoplolepis gracilipes Little fire ant Wasmannia auropunctata Fire ant Solenopsis invicta INVASIVE SPECIES : OTHER EXAMPLES I) SNAKES : Boiga irregularis Guam island II) AMPHIBIANS : Lithobates catesbeianus (Bullfrog) III) FISH : Pterois sp. (Lionfish) Boiga irregularis INVASIVE SNAKE - One example : Boiga irregularis, introduced possibly by US Army in Guam Island after the World War II - It is an opisthoglyphous snake, i.e. a venomous snake, not dangerous for adults but possibly dangerous for children. - Destroyer of the microendemic vertebrates fauna : rodents, bats, birds, lizards. Lithobates catesbeianus AMPHIBIA - As snakes, the invasions of vertebrate species result from a human introduction, voluntarily or not, sometimes with the idea of the elimination of a “vermin” CONCLUSIONS - Role of climate changes limited, except in some arthropods (Lepidoptera, Coleoptera), and some vertebrates (snakes) - Role of human factors important concerning invasive venomous species (arthropods but also vertebrates), including some cases of adaptation of venomous species to anthropic environments.