Our eri silkmoth (Samia ricini) larvae have all finished spinning cocoons so we collected mass data. And another brood finished. The last of the larvae finished spinning, so like always, we collected all of them in a tub and weighed them. There are 20 in total, and this time they are quite large compared to previous rearings. This is our fourth rearing of Samia ricini; summary stats are listed below for this brood, as well as two previous broods (the third brood of winter 2016 was never recorded, but was very small). Note that this brood was reared on Liquidambar while the other two were on Prunus, and the fall 2016 brood was of a different lineage. Summary Statistics for Samia ricini Cocoon Mass: Mean Std Dev Median Min Max N Fall 2016 2.221 0.356 2.1 1.6 2.8 14 Spring 2017 1.773 0.337 1.7 1.2 2.5 33 Summer 2017 2.218 0.294 2.19 1.78 2.86 20 The majority of cocoons this time were 2 g or larger which is quite good, and masses were less variable than in previous broods. Of the three broods, both the fall 2016 and summer 2017 broods were significantly larger in mean mass than the spring 2017 brood (p=0.0002 and p<0.0001, respectively), and between those two larger broods, there was no significant difference in mean mass. Shown above are this brood's cocoons compared to the fall and spring cocoons. The spring are visibly much smaller, and the silk was thinner and and more papery, rather than thick and fluffy. The fall cocoons look about the same size visually as this time's cocoons, but as they were of a different lineage, the shape of the cocoons were flatter and less round. Most likely the spring rearing produced small cocoons because of much more severe overcrowding in the final instar compared to in the other two and the food quality was not as good. Or, maybe it was the host plant species that made the difference, as this time we used Liquidambar for the first time rather than Prunus. Perhaps Liquidambar was a better host than Prunus, and the reason why the fall brood was on par with the summer brood because that lineage was larger or utilized Prunus more efficiently. ![]() Authors Alan Liang
Comments
|
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 |