DESCRIPTION
The video "The Caterpillar of the Small tortoiseshell • Aglais urticae"
shows some details about the caterpillar's life until the butterfly hatches.

-- the eggs of Aglais urticae and few hours old caterpillars

-- A nest of Aglais urticae caterpillars two days after hatching

-- The feeding caterpillar before pupation.

-- The period of Caterpillar rambling.

-- The formation of a silk cushion, which is used by the last extremities to hook the Caterpillar and later on the Cremaster of the chrysalis.

-- The disengagement of the last remaining extremities before pupation.

-- The Cremaster in action, while hooking to the silk cushion.

-- The complete pupal molt

-- The imaginal molt and the adjustment of the proboscis

Before pupation, fully-grown caterpillars of Aglais urticae stop feeding and empty their alimentary tract. Thereafter they enter the period of rambling, walking around for about one day, searching for an appropriate branch to hook on for pupation. Once found the caterpillar weaves a silk cushion, which is made of very tiny silk loops. The last extremities of the caterpillar hook to the silk cushion which later on is repeated by the cremaster during pupation. Finally the caterpillar (position upside down) liberates the remaining extremities. Thereafter the chrysalis develops inside the caterpillar and all what is left over, is its cuticle, which is shed at pupal molt. At the end of this process the pointed cremaster appears and hooks to the silk cushion, securing the body of the chrysalis. Directly after this molt the soft cuticle of the chrysalis appears somewhat wrinkled but gets very rapidly unwrinkled and smooth, which is done by the contraction of abdominal muscles an by hemolymph pressure. By this process the chrysalis finally is shaped to its characteristic appearance. In the course of one to two weeks (temp. dep.) the butterfly develops inside the chrysalis and finally leaves it by opening a preformed lid of the chrysalis. When hatching it can be seen, that the later proboscis is made of two parts which join in a rolling/unrolling process, and thus forming the proboscis.

SOMETHING ABOUT HORMONES:
The metamorphosis of a butterfly (caterpillar → chrysalis → butterfly), is controlled mainly by two hormones, namely ECDYSON and JUVENILE HORMONE. Ecdyson is needed throughout the whole developmental process and Juvenile Hormone (JH) determines the character of the development. As long as JH dominates Ecdyson the caterpillar continues to develop as caterpillar performing several molts. When finally the titer of JH is reduced below the level of Ecdyson the caterpillar will undergo transformation into a chrysalis. Once pupated JH is abolished and Ecdyson dominates the developmental processes. The butterfly develops inside the chrysalis and finally hatches.

Camera: Sony FDR--AX 100E 4K • Canon XLH1 • JVC GC-PX100 • Canon EOS 70D + Lupenobjektiv Canon MPE 65

MUSIC
"Deliberate Thought" by Kevin MacLeod (incompetech.com) Licensed under Creative Commons: By Attribution 3.0http://creativecommons.org/licenses/by/3.0/

KLAUSEL, CONDITION, CLÁUSULA
This video is free of charge for private and non-commercial educational purposes.
Please respect the right of author (copy right ©)

HASHTAGS
#HiddenBiologicalEvents #Tortoiseshellbutterfly #urticae

свернуть