Today we were lucky enough to found a western tiger swallowtail (Papilio rutulus) egg on a willow tree at Cerrito Creek! Ever since we have gotten some caterpillar action going this month, we've been having to make several trips a week down to Cerrito Creek (just before Albany Hill) in order to pick willows (Salix), alder (Alnus rubra), and ceanothus (Ceanothus). The place is just packed full of life at this time of year and thus far we have never failed to find something interesting. After encountering so many of these "random" caterpillars on these trips simply by chance and without any serious intention of doing so, we really started to question whether it was truly so difficult to find so-called "highly-cryptic" species like western tiger swallowtails (Papilio rutulus) or Smerinthus opthalmica. Surely, these can't be too much harder to overlook than speckled green fruitworm moth (Orthosia hibisci quenquefasciata) larva of which we have found twice in two weeks. We don't have the best eyes around (nearsighted) but we figured that unless they truly didn't exist on the trees of Cerrito Creek, we should be able to find them within time. With that said, it still came as a complete shock when we found a freshly laid Papilio rutulus egg lying around on the lower side of a willow tree (not more than 4-5 feet off the ground) in full sun, smack in the center of the last segment of trail just as we were about to head home. This was complete chance encounter. One moment you are walking along the trail and the next you are staring less than a foot away from a shiny object to the right! There are few other events where we have been as lucky as this one. The egg is clearly at most a day old. More likely it was laid just today, which was one of the hottest days of this year so far. The perfect timing with the perfect whether. The only strange thing was that the exact location seemed more or less arbitrary. Not only is it hard to even imagine an adult rutulus flying so low--the rumor is that they typically lay on tree tops, the leaf was definitely not a particularly desirable one. This egg is actually quite different then the Papilio glaucus egg we have to our surprise. To be precise, this rutulus egg is much larger (a little under 2 mm compared to the glaucus' 1.5 mm) and somewhat flat rather than perfectly spherical. This conforms with the pattern we have seen with many of our west coast species as compared to counterparts in other regions: the eggs tend to be proportionally larger whereas the adults average smaller. We have noted this in Smerinthus opthalmica and Hyalophora euryalus and have heard reports of this in Californian Antheraea polyphemus; and for some reason Battus philenor hirsuta tends to lay larger egg clusters than the nominate species. It also seems to be slightly lighter in color (yellower) than the glaucus egg when it was fresh. We are now hoping for two things to happen: first, for the hybrid glaucus × rutulus egg to develop properly and hatch and second, for this new egg to hatch (into what we would prefer to be a female). It would really be an incredible opportunity to observe the two growing side by side. Below are the two eggs shot together for comparison. ![]() Authors Brian Liang
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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 |