The Painted Lady caterpillars (Vanessa cardui) that we found at Tilden Park on 7/9 are developing at an incredible speed and the older of the two is already ready to pupate. When we first found two Painted Lady caterpillars (Vanessa cardui) exactly nine days ago on 7/9, the older of the two was in fourth instar and the younger one was in third. For the first few days after we started keeping them, we were struggling to provide them with an ample supply of fresh Milk Thistle (Silybum marianum) leaves, which was the host that we found them on. Milk Thistle is extremely common around here as a weed but for some reason most of it had either been pulled out by city maintenance or simply died on its own now that it is getting late in the season. The only thistle we could find were tiny little patches far from home regenerating from plants that had been cut down. They were so small that they were hardly identifiable as Milk Thistle without the characteristic tall stem and poofy pink flowers! More than once, we had to let the two starve in their little plastic cup for up to half a day. Normally that would be pretty terrible, quite obviously. Molting in caterpillars is completely regulated by the endocrine system and juvenille hormone (JH) doesn't care whether the caterpillar is well fed or not; it will very slowly continue to drop regardless and eventually force the caterpillar into apolysis unless it has already died from starvation, of course. This would take a hefty toll both on the caterpillar's growth rate and overall size. Not to mention the weather has been at its coolest this whole summer this past week (low to mid 60's with fog) and, since caterpillars are cold-blooded, growth rate is positively correlated with higher temperatures. But these Painted Ladies are crazy, to say the least, and are some of the fastest growing caterpillars in proportion to their size (usually larger caterpillars take longer to grow and vice versa) that we have ever witnessed regardless of the unfavorable conditions. In just nine short days, the older caterpillar powered through the fourth instar, molted into fifth, and is now in the "J" formation prepupa (typical of brush-footed butterflies [family Nymphalidae]). The younger has raced from third instar all the way to fifth and will also surely be a prepupa within a day or two. Now that is really fast. Most caterpillars of their size (about two inches but relatively narrow-bodied) usually take almost a week to get past the fourth instar and around one week for the fifth and final one. - 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 |