Today we have finally found a good way to get our fertilized Mexican Bush Katydid females (Scudderia mexicana) to oviposit! For weeks now since our first Mexican Bush Katydid female (Scudderia mexicana) got mated we have been struggling to find a way to get them to lay eggs. Yesterday, we made a post about how we actually found a group of six eggs layed by our first female in a slit created by a piece of tape and a paper towel in our glass aquarium tank. While it was surely a great discovery for us, what puzzled us is why the katydid insisted on ovipositing only in the tank and not anywhere in the actual breeding enclosure that we provided it -- a 2 x 2 x 4 feet screened box with a live potted passionflower vine (Passiflora) in it. The leaves of the passionflower vine looked as excellent as any leaf for ovipositing; they were large and thick, easily enough room for the katydid to insert her scimitar shaped ovipositer in. It has been weeks now and not a single egg that we know have in the enclosure. While, SINA recommends depriving the female for a few days of suitable ovipositing sites, this is quite ironic. We had put the female who laid the six eggs into the tank in an attempt to deprive of proper sites (obviously that unexpectedly failed, in a good way) and yet she chooses not to lay in the enclosure where there should be plenty of places. Starting from yesterday, we noticed two of our females, presumably fertile, struggling with all of their might to oviposit in a small tag sticking out from the top of the enclosure. The tag was basically a thin strip of plastic (only one layer) so there was no possible way that the females could oviposit in it, but they kept obsessing over it, biting at the edges with their jaws and stabbing it with their ovipositers as if their life depended on it. Why, oh why were they so interested by this tag when there is a live plant in there? Well, the make a long explanation short, the only thing we could come up with is that the females require a very specific position for laying eggs. Actually, specific ovipositing position is something that can be seen in a lot of insects. Simply put, the female can't lay unless her ovipositor (whatever shape it may be) is not in a convenient angle or location on the substrate to do so. In the case of these katydids, we noticed that unlike the leaves on the passionflower, the tag was sticking in just the right way such that the female could crawl directly onto the edge and position her ovipositer comfortably, without falling off. In nature, they probably search all day for suitable places, which isn't terribly difficult with the enormous diversity of the plants growing around but in our enclosure the passionflower vine probably just didn't cut it. To test our prediction, we took one of the females inside and put her on an orchid flower (the ornamental plants kind you can find in most grocery stores). Like mentioned before, being able to crawl directly along the edge of the substrate is critical. An orchid flower is unique in that the petals are very flat, rigid, and thick (roomy for ovipositing) like a disc which allows the katydid to have a firm grip crawling on it without wobbling (like on a flimsy leaf or flower). The clincher is the orientation: the orchid flower was growing vertically and not somewhat horizontally like most flowers (the latter, I imagine, would be awkward to crawl on the edge of). But even with the convenient morphology of the orchid flower, we had to help her a bit sometimes, allowing her to crawl on our hand while ovipositing on the edge. Within a few minutes, she had laid four eggs, methodically feeling around with her mouth-parts for the edge and then nibbling at it when she found it so she could insert her ovipositer into it. Once in, there is a short pause as she prepares to lay. The egg is actually laid when she slowly withdraws the ovipositer; it is left within is slit created by the ovipositer. The entire process only takes a few minutes (shown in the videos below). After each egg, she would thoroughly clean her ovipositer with her mouth. Eventually, we brought in the three other females to lay. One of them, our first fertilized katydid (who also laid the eggs in the tank) seemed even more enthusiastic and laid immediately. However, the other two seemed to have no reaction whatsoever; one of them even started to eat the orchid. We assumed that they weren't fertile and took them away. By the time the two fertile females were done, we had collected 20 or so. At last, we have found a successful technique to get them to lay the eggs! Mexican Bush Katydid (Scudderia mexicana) Ovipositing (1)* Mexican Bush Katydid (Scudderia mexicana) Ovipositing (2)* Mexican Bush Katydid (Scudderia mexicana) Ovipositing (3)* * Shown in 4x speed - 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 |