{"id":46889,"date":"2013-08-16T07:51:44","date_gmt":"2013-08-16T06:51:44","guid":{"rendered":"http:\/\/focusingonwildlife.com\/news\/?p=46889"},"modified":"2019-12-23T00:34:44","modified_gmt":"2019-12-22T11:34:44","slug":"common-hawker-or-sedge-darner-emergences","status":"publish","type":"post","link":"https:\/\/focusingonwildlife.com\/news\/common-hawker-or-sedge-darner-emergences\/","title":{"rendered":"Common Hawker or Sedge Darner emergences"},"content":{"rendered":"

Emergences d’Aeschnes des joncs – Aeshna junceaOdonata – Aeshnidae – Il n’y a rien de plus beau qu’une libellule qui émerge de son exuvie mais rien n’est jamais gagné à aucun stade de la vie de ces insectes extraordinaires.J’ai trouvé cette larve mourante sur la mousse de la tourbière que je scrutais pour trouver des émergences.<\/p>\n

En la regardant de près pour comprendre le problème j’ai tout de suite compris que la libellule s’était épuisée à tenter sa sortie mais de la mauvaise manière.Le dessus du thorax puis la tête en suivant auraient du émerger en premier et par le dos. Hors ici, on voit que la tête est restée coincée par les bords de l’exuvie et chaque œil en a été marqué de façon identique, voir la flèche blanche ci-dessous:<\/p>\n

Nothing is more beautiful that a dragonfly merging from its exuvia but nothing is ever won at any stag of these extraordinary insects’ life. I found this dying larva on the peat bog moss I was scrutinizing to find emerging dragons. By looking at it closely to understand the problem I noticed at once that the dragonfly was exhausted trying to emerge but it had done so the wrong the way.
\nThe top of the thorax then the head should would have emerged first through the back. But here, we can see that head remained stuck by the edges of the exoskeleton and each eye had an identical indent below… see the white arrow below:<\/p>\n<\/p>\n

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Aeshne juncea<\/figcaption><\/figure><\/p>\n

Ici la flèche du dessus montre les bords de l’exosquelette qui recouvre encore une partie de la face de l’insecte et la seconde montre plus précisément comment ces bords ont imprimé une marque creuse sur le bas de chaque œil. En passant, on peut remarquer le masque sous la tête: c’est la lèvre inférieure de la larve qui se projette en avant pour saisir ses proies aquatiques de façon fulgurante.Inutile de dire que cet individu n’a pas survécu.<\/p>\n

Below, the top arrow shows the exuvia’s edges still covering part of the insect’s face and the second one shows precisely how these sharp edges have damaged permanently the eyes. Notice the mask under the head: it is the lower jaw that extends to reach an aquatic prey.No need to say this poor thing didn’t make it.<\/p>\n<\/p>\n

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Aeshne juncea<\/figcaption><\/figure><\/p>\n

Exuvie d’Aeschne des joncs: on voit la sortie parfaite de la libellule par le dos.Voir une émergence complète et une explication sur ces fils blancs qui pendent, les trachéobranchies [ICI…].<\/p>\n

Exuvia showing the perfect hatching of a dragonfly; to see a complete larva emergence and read an explanation on the trachea-gills (the hanging white thread), follow the link above:<\/p>\n<\/p>\n

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Aeshne juncea<\/figcaption><\/figure><\/p>\n

A un stade ultérieur, ce juvénile a émergé mais les ailes ne sont pas correctement déployées. Les raisons sont multiples; elles émergent dans un milieu surpeuplé de libellules qui ne se font aucun cadeau et se tamponnent sans cesse dans le but de s’éliminer mutuellement – aussi jolies soient-elles, ce sont des tueuses et des prédateurs redoutables! Une herbe rigide mal placée pourrait avoir empêché leur déploiement final. Dans d’autres cas il suffit que l’hémolymphe (sang de la larve, un liquide vert) ne se répartisse pas de façon régulière partout.<\/p>\n

At further stages things can also go wrong; here the wings did not spread properly. The reasons are many; they emerge in a hostile environment over populated with other dragons which are chasing each other often to death. As beautiful as they might be, they are extraordinary killers and predators. Also, a rigid blade of grass can be in way of the deploying wings and in other cases, the haemolymph (the green larva’s blood) does not reach regularly everywhere.<\/p>\n<\/p>\n

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Aeshne juncea<\/figcaption><\/figure><\/p>\n

Enfin, voici des individus pour lesquels l’émergence a été parfaite et sont prêts pour leur vol inaugural; tous leurs sens en alerte, ils décollent presque sous mes pieds mais heureusement j’ai souvent le temps de les repérer et de pouvoir leur tirer le portrait avant qu’ils ne quittent leur vie aquatique pour de bon:<\/p>\n

Finally, here are a couple of individuals whose emergence was perfectly successful and are ready for their first flight. They are so ready that the slightest movement catches their eye and they flee as I approach. Fortunately, I manage to take a few pictures once in while, before they abandon their aquatic life for good.<\/p>\n<\/p>\n

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Aeshne juncea<\/figcaption><\/figure><\/p>\n<\/p>\n

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Aeshne juncea<\/figcaption><\/figure><\/p>\n<\/p>\n

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Emergences d’Aeschnes des joncs – Aeshna junceaOdonata – Aeshnidae – Il n’y a rien de plus beau qu’une libellule qui émerge de son exuvie mais rien n’est jamais gagné à aucun stade de la vie de ces insectes extraordinaires.J’ai trouvé cette larve mourante sur la mousse de la tourbière que je scrutais pour trouver des […]<\/p>\n","protected":false},"author":287,"featured_media":2147085,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"fifu_image_url":"","fifu_image_alt":"","footnotes":""},"categories":[6984,5],"tags":[2266,3015,5302,2407,2571,598,3016],"class_list":["post-46889","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-blogs","category-wildlife","tag-dragonfly","tag-dragonfly-emergence","tag-exuvia","tag-france","tag-noushka","tag-odonata","tag-sedge-darner"],"_links":{"self":[{"href":"https:\/\/focusingonwildlife.com\/news\/wp-json\/wp\/v2\/posts\/46889","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/focusingonwildlife.com\/news\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/focusingonwildlife.com\/news\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/focusingonwildlife.com\/news\/wp-json\/wp\/v2\/users\/287"}],"replies":[{"embeddable":true,"href":"https:\/\/focusingonwildlife.com\/news\/wp-json\/wp\/v2\/comments?post=46889"}],"version-history":[{"count":0,"href":"https:\/\/focusingonwildlife.com\/news\/wp-json\/wp\/v2\/posts\/46889\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/focusingonwildlife.com\/news\/wp-json\/wp\/v2\/media\/2147085"}],"wp:attachment":[{"href":"https:\/\/focusingonwildlife.com\/news\/wp-json\/wp\/v2\/media?parent=46889"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/focusingonwildlife.com\/news\/wp-json\/wp\/v2\/categories?post=46889"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/focusingonwildlife.com\/news\/wp-json\/wp\/v2\/tags?post=46889"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}