Today we were quite disappointed to find that our newly molted Gray Hairstreak (Strymon melinus) chrysalises was being eaten by a fifth instar conspecific! The family Lycaenidae is quite famous for the relationship its caterpillars have with ants. Most species produce honeydew to attract and appease ants who may inadvertantly act to protect the larvae by warding of insect predators and parasitoids. Honeydew is comprised of a combination of sugars (glucose, fructose, and sucrose) and amino acids in set ratios that may only attract a specific species of ant. The larvae is protected from the ants themselves (who may normally bite at or attack caterpillars) through the evolution of a unique body form: a tiny head and legs that can be retracted underneath the short and stout body, the slug-like gliding movement while in retracted, extremely thick exoskeleton (sometimes chitinized!), and in some cases appeasing pheromones or sounds. In quite a few species, larvae are carnivorous (an highly cannibalistic) such as those that use honeydew to get ants to carry them into their nests. Once inside the nest, larvae start attacking ant grubs. It is not difficult, then, to see why lycaenid caterpillars are notoriously cannibalistic in the lab, when housed together. The lycaenid Strymon melinus, the Gray Hairstreak, is part of a group that is not so aggressive; they are certainly not carnivorous by choice. The ant-larvae relationship, as far as we know, is not quite so extreme. The two fourth instars that we collected on mallow (Malva) ate foliage like normal caterpillars and did not behave aggressively towards each other. The newborns, living in the same petri dish, have not eaten each other yet (at least we think!). The scary part of the story unfolded today when we discovered a fourth instar rolled up around and feeding on a chrysalis that pupated today, both of which were confined in a small petri dish with a very dry leaf of mallow that was probably unappetizing. The opportunistic caterpillar clearly took advantage of the soft, teneral chrysalis and bit a huge hole at the thorax which was spewing an ungodly amount of blood when we arrived on the scene. Seeing this, we quickly made the decision to remove the other fourth instar inside the dish which had turned brown yesterday (is going to pupate) out to a dish of its own. - 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 |