Our Eri Silkmoths (Samia ricini) have begun to eclose. These were originally obtained from a Europe sourced brood and reared indoors on plum (Prunus). They began hatching on 8/22/16 and spinning cocoons on 9/29/16. Today we had four Eri Silkmoths eclose including the pupa from the cut cocoon. Two emerged at nearly the same time around 1:00 PM while the other two eclosed around 6:00 PM. We caught neither of them in the act of escaping the cocoon but it was evident that they squeezed through the trap hole at the top of the cocoons as it was wet and partially dissolved. All four had partially expanded wings by the time we were aware that they had eclosed so we couldn't take any photos of the newly eclosed moth. For the first several hours after the wings expanded, the moths would hold them folded and hang at a 90-180 degree angle, but once they hardened, they relaxed and spread their wings across. disappointingly, the second two males the eclosed has bent and creased wings which is a common problem that samia ricini suffers from due to excessive inbreeding. After inspecting the genitalia, we determined that all four were males which is rather disappointing since we need a pairing, but it's not very surprising since like other Saturniidae, the males tend to have faster growth in the larval and pupal stages and eclose earlier. Thus, hopefully we will get a few females in the next few days before the males become too weak and tattered to mate. The moths have primarily greyish brown wings with white patterns and grey margins, and a white body with brown streaks. In addition there is a golden crescent on each fore and hindwing, and a black spot at the tip of each forewing. The wing size for this species is incredibly large in relation to the body size, being around 5 inches across. It's not hard to see how the Atlas Moth (Attacus atlas) which is closely related with similar body proportions can obtain such a large wing span. In addition to the generally large wing to body size ratio, the shape of the wings themselves make them look extremely large, since the tip of the forewings are curved out and elongated and the hindwings are very elongated and pointy in the downward direction. To put things into perspective of how disproportionately large their wing size is, the Samia ricini pupae were mostly under 2.0g while Smerinthus ophthalmica pupae were over 3.0g, but the adult Eri Silkmoth looks at least two times larger than the Ophthalm Sphinx adult. These moths are truly incredibly beautiful to see in real life, but its just so unfortunate that they had to eclose at this time of year rather than diapausing and eclosing next Spring. Assuming all 14 cocoons will eclose, in order to sustain our breeding stock we will need to rear up another brood which will be extremely difficult during this season since we can hardly find any host plants and the weather is not ideal. - Alan
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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)
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![]() ![]() 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 |