As the days past, we are discovering that more and more of our wild-caught Pipevine Swallowtail chrysalises (Battus philenor) had been parasitized by chalcid wasps (Brachymeria ovata). Anybody who has ever collected caterpillars or chrysalises from the wild has probably encountered a number of parasitoids. It is a risk we all have to take because you never know their there until its too late! Starting on 6/26, we first noticed that two of our Pipevine Swallowtail (Battus philenor) chrysalises -- one directly wild-caught and the other from a fifth instar caterpillar that had been wild-caught -- had started developing strange red splotches on them. At the time, we were unsure whether this was normal or not since it was our first time really seeing Pipevine Swallowtail chrysalises at all. But what was alarming was that the red splotches were not symmetrical. Moreover, it also didn't make any sense that they would appear on some chrysalises and not others and that they showed up randomly and not immediately after the chrysalises had completely hardened after pupation. For example, the wild-caught one had clearly pupated for several days before we collected it because it was completely hardened (a process that takes at least two days) while the other one developed the spots immediately following pupation. In a few days, we confirmed our suspicions on 6/28 that something was up with these two chrysalises, as well as a with a third wild-caught one we found that day. The truth was, all three of the chrysalises seemed quite dead at that point so we thought it would okay to just pierce one open and investigate. Upon making an incision in the first wild-caught chrysalis with a pointy toothpick, we discovered that the chrysalis was, indeed, very much dead and hollowed out (eaten) by a very large parasitoid maggot. We later identified this as a species of chalcid wasp, specifically Brachymeria ovata. In the end, this was not a big surprise. I mean what else could have killed them besides simply drying out? In the past few days we are beginning to discover that many more of our recent chrysalises have been parasitized. Almost half of them at this point are highly suspect. Just like any other species of caterpillar, the Pipevine Swallowtails have their own natural enemies. Unlike most caterpillars, they don't have to worry about external predation because they are protected by their toxic aristolochic acids; parisitism is actually their biggest problem. The vast majority of the parasitized chrysalises have been undersized; none of the healthy ones are undersized. In hindsight, we were probably wrong about there being such a massive size variation in these species. Then again, the smaller ones do tend to be eaten alive faster and therefore show the red splotches much faster (some of the big chrysalises that seem healthy may still eventually turn out parasitized). Luckily, we didn't actually have too many caterpillars/chrysalises that were wild-caught. The bulk of our stock right now comes from the 200+ eggs we have collected so hopefully all of the surviving members from these groups are totally fine. - 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 |