Almost all of this summer's Hyalophora cecropia larvae have spun cocoons, so we decided to sort them out share some thoughts on this year's rearing. Though there are still two larvae left that have yet to spin cocoons, we went ahead and sorted out all the finished cocoons. We have a total of 26 cocoons (not including a couple that we disposed of because they seemed dead). There are 21 from the first pairing, 4 from the second, and 1 from the third. From first instar to cocoon, mortality was obviously quite high, especially for the second and third strains. It seemed most larvae from these strains got diseased before making it to the fifth instar, while a decent amount of the first pairing larvae were already in fifth before disease started spreading which explains why many more survived. The cocoons are all quite variable in size, shape and color. Some are pale and greyish while others are a rich brown color. There doesn't seem to be any difference between the maple and serotina cocoons. We removed the dead plant material woven into the cocoons as best as possible and weighed each one. The weights for the first pairing cocoons were 4.02, 4.52, 3.62, 5.30, 5.15, 5.19, 4.38, 4.04, 4.06, 3.05, 7.27, 4.04, 4.86, 5.95, 3.28, 4.77, 3.62, 4.72, 6.66, 4.50, and 5.93 grams; for the second pairing cocoons were 3.70, 3.92, 4.89, and 4.95 grams; and for the third pairing cocoon was 3.37 grams. Sample size is definitely too small to try comparing weights between the lineages, and there were probably a number of confounding factors due to disease and the way they were reared. anyway. Overall, this year's cocoons are surprisingly small compared to those from previous years. We've never had cocoon weights as low as the 3-4 gram range in the past, which is extremely small in general, especially if any are female. We had originally expected that this year's cocoons would be larger than the previous rearings back in California, since we have access to more typical host plants and are in their native environment here in Ithaca. Although it is true that better host quality (?) and the warmer and wetter Ithaca summers would have definitely helped their growth, we suspect any positive effects of these factors could have been superceded by the negative effects from the severe overcrowding compared to previous rearings. We attempted to rear far more larvae than the previous rearings and had many more larvae make it to the final instar which really overwhelmed us. Thus, it seems this year was a year of quantity over quality for cecropia. ![]() Alan Liang Alan Liang is a student at Cornell University in Ithaca, New York pursuing an undergraduate degree in entomology. He is co-owner and a main contributor of the Liang Insects blog and photographs.
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Timeline 2017–present
Ithaca, New York This timeline is a series of daily posts recording our observations and experiences with various insects (primarily Lepidoptera) around the Cornell University campus in Ithaca, New York, starting from the time we moved here in 2017. As this is a personal blog, we try to keep collections/rearings for university research and course work to a minimum, and mainly focus on just the species we catch and raise for our own fun and interest. Posts prior to this time can be viewed at Timeline 2012-2017: Albany, California, though there is occasionally some crossover when we have returned home during breaks or reared stock derived from home (see Albany, California Updates). Archives (232)
July 2020 (1) August 2019 (2) July 2019 (35) June 2019 (46) May 2019 (20) March 2019 (1) January 2019 (1) November 2018* October 2018* September 2018 (1)* August 2018 (9)* July 2018 (11)* June 2018 (22*) May 2018 (18)* April 2018 (2)* January 2018 (6) December 2017 (5) November 2017 (1) October 2017 (5) September 2017 (26) August 2017 (19) *Currently, a significant portion of 2018 posts are missing. The notes/photos for this time period are saved on our personal files but the posts were never built due to a busy schedule that year. We are still actively building these posts when we have the time. 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 Agraulis vanillae Allancastria cerisyi Amphion floridensis Ancyloxypha numintor Antheraea polyphemus Battus philenor hirsuta Callosamia promethea Colias eurytheme Citheronia regalis Cupido comyntas Danaus plexippus Darapsa myron Diadema inscriptum Epargyreus clarus Erynnis baptisiae Estigmene acrea Euchaetes egle Eumorpha pandorus Hemaris diffinis Hyalophora cecropia Limenitis archippus Liminitis arthemis arthemis Limenitis arthemis astyanax Manduca sexta Orgyia leucostigma Pachysphinx modesta Paonias myops Papilio cresphontes Papilio eurymedon Papilio glaucus Papilio polyxenes asterius Papilio rutulus Papilio troilus Papilio zelicaon Pyrgus communis Samia ricini Smerinthus ophthalmica Speyeria cybele Sphecodina abbottii Vanessa atalanta Vanessa cardui Vanessa virginiensis Lepidoptera Hybrids Papilio polyxenes asterius × Papilio zelicaon Orthoptera Conocephalus sp. Dissosteira carolina Melanoplus femurrubrum Neoconocephalus ensiger Neoxabea bipunctata Phasmatodea Carausius morosus Diapheromera femorata Mantodea Mantis religiosa Albany, California Updates |