One of our fifth instar Pipevine Swallowtails (Battus philenor) that had become a prepupa actually managed to pupate without dying and ended up as a caterpillar-chrysalis intermediate. Over the past week we have had a total of three of our fifth instar Pipevine Swallowtails (Battus philenor) unexpectedly messy our containers with their loose stool. We have actually documented a sixth instar in every single other of our other captive raised caterpillars thus far; as of today there are 27 sixth instar caterpillars, 11 sixth instar formed prepupae, and 14 sixth instar formed chrysalises. But for some reason these three sickly looking individuals in a particular colony decided to do this. Clearly, the endocrine functions in these Pipevine Swallowtails is out of control. Their size fluctuates naturally fluctuates more than any other caterpillar we have ever reared, and not just because the females tend to be larger than the males (this is actually the case in many species), we suspect, due to juvenille hormone (JH) levels in the caterpillars being so out of whack. Five larval instars is not a normal occurrence, at least in our particular regional race and is probably simply caused by a lack of JH. Suggested, of course, by the fact that the vast majority of them went on to the sixth instar and the ones that didn't just died. Today, we finally got one of the fifth instar prepupae to pupate though, without just dying. The first two in the colony had just sat there, developing into pupa but never actually completing final ecdysis (so basically, they died as a chrysalis wrapped in caterpillar skin). We had a similar experience with the fifth instar pupaters we had earlier in June. But this time, though the fifth instar really did pupate, it ended up turning into a caterpillar-chrysalis intermediate, supporting our conclusion of hormonal involvement. It didn't have enough JH to stimulate the sixth larvae-to-larvae molt, but had just too much such that the chrysalis still had caterpillar parts. At this point, it will probably die within a day. We can't image what would happen if it didn't die and actually eclosed as some strangely deformed butterfly, especially because it is a puny 0.3 grams; it would clearly be incapble of breeding! On another note, we noticed today that what we believe to be a normal fifth instar is surprisingly large. For week we have been complaining about how our captive raised caterpillars are, on average, much smaller than their wild caught counterparts due to us rearing them at extremely high densities, poor food quality, and disruptive disease outbreaks from bad sanitation. The largest sixth instar caterpillar we have is currently only 2.4 grams (they shrink to roughly half the size when they pupate!) and our largest chrysalis only 1.2 grams while our largest wild caught formed chrysalises from June were 1.5 grams. The large fifth instar in question is now in apolysis for sixth and already a whopping 1.4 grams, with a head capsule unrivaled by any of the other seven fifth instars we have left or any of the 20-30 fifth instar head capsules that we saved. Though big, its head capsule isn't quite as big as the average sixth instars' but at first glance we still could have mistaken it for a small sixth instar trying to make up by going into a seventh instar! The left and middle show the fifth instar formed chrysalis, complete with a distinguishable caterpillar head! The left shows it next to a normal (and normal sized) chrysalis. - Brian
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Timeline 2012–2017
Albany, California This timeline is a series of daily posts recording our observations on and experiences with various insects in Albany California and surrounding areas, from 2012-2017. Since we did not publish this site until 2016, posts before that were constructed retroactively. Starting in August 2017, we moved to Ithaca, New York; posts from there on can be viewed at Timeline 2017-present: Ithaca, New York. Archives (1,011)
August 2017 (49) July 2017 (121) June 2017 (79) May 2017 (77) April 2017 (91) March 2017 (35) February 2017 (12) January 2017 (10) December 2016 (12) November 2016 (26) October 2016 (49) September 2016 (84) August 2016 (94) July 2016 (99) June 2016 (53) May 2016 (21) April 2016 (4) January 2016 (1) August 2015 (3) July 2015 (3) June 2015 (2) June 2014 (3) May 2014 (1) April 2014 (3) March 2014 (3) December 2013 (2) November 2013 (2) October 2013 (5) September 2013 (11) August 2013 (15) July 2013 (9) June 2013 (5) May 2013 (4) April 2013 (3) March 2013 (2) February 2013 (3) January 2013 (2) December 2012 (2) November 2012 (1) October 2012 (2) September 2012 (2) August 2012 (5) July 2012 (1) June 2012 (1) Authors
![]() ![]() Full Species List (Alphabetical by scientific name) Note: - Not every species we encounter is necessarily presented on this site, rather a selection of those that were of particular interest to us and that we felt were worth documenting. - We can't guarantee that all species have been identified accurately, particularly taxa we are not as familiar with. Lepidoptera Actias luna Adelpha californica Agraulis vanillae Allancastria cerisyi Antheraea mylitta Antheraea polyphemus Anthocharis sara Argema mimosae Attacus atlas Battus philenor hirsuta Bombyx mori Caligo atreus Callosamia promethea Coenonympha tullia california Citheronia regalis Cricula trifenestrata Danaus plexippus Eacles imperialis Erynnis tristis Estigmene acrea Eumorpha achemon Eupackardia calleta Furcula cinereoides Heliconius erato Heliconius hecale Heliconius sapho Heliconius sara Hyalophora cecropia Hyalophora columbia Hyalophora euryalus Hylephila phyleus Hyles lineata Junonia coenia Langia zenzeroides formosana Lophocampa maculata Manduca sexta Morpho peleides Nymphalis antiopa Orgyia vetusta Orthosia hibisci quenquefasciata Pachysphinx modesta Papilio cresphontes Papilio eurymedon Papilio glaucus Papilio machaon oregonius Papilio multicaudata Papilio polyxenes asterius Papilio rumiko Papilio rutulus Papilio zelicaon Phyciodes mylitta Phyciodes pulchella Pieris rapae Plejebus acmon Poanes melane Polites sabuleti Polygonia satyrus Pyrgus communis Rothschildia jacobaeae Samia cynthia advena Samia ricini Smerinthus cerisyi Smerinthus ophthalmica Strymon melinus Trichoplusia ni Uresephita reversalis Vanessa annabella Vanessa atalanta Vanessa cardui Unidentified Lepidoptera Hybrids Papilio glaucus × Papilio rutulus Papilio polyxenes asterius × Papilio zelicaon Orthoptera Melanoplus devastator Phaneroptera nana Pristoceuthophilus pacificus Scudderia mexicana Trimerotropis pallidipennis Phasmatodea Carausius morosus Phyllium giganteum Mantodea Mantis religiosa Phyllocrania paradoxa Hymenoptera Apis mellifera Bombus vosnesenskii Brachymeria ovata Linepithema humile Pediobius sp. Polistes dominula Xylocopa varipuncta Unidentified Diptera Lucilia sericata Unidentified Hemiptera Brochymena sp. Leptoglossus sp. Nezara viridula Odonata Argia vivida Libellula croceipennis Coleoptera Coccinella septempunctata Cycloneda polita Diabrotica undecimpunctata Hippodamia convergens Araneae (Class: Arachnida) Araneus diadematus Phidippus johnsoni |