Over the years, we noticed some interesting differences in color morphs in Mediterranean Katydids (Phaneroptera nana) and Mexican Bush Katydids (Scuderria mexicana) we have found. Color variation is extremely common among insects just like humans exhibit an endless array of unique skin tones. In cryptic species, the most common major color groups are green and brown, for obvious reasons. Through the years we have encountered both of these color forms in both Mediterranean (Phaneroptera nana) and Mexican Bush (Scudderia mexicana) katydids though it is not quite the same between the species. In P. nana, we have found the brown morph to be relatively more common, perhaps making about about 10% of the population based on our sample size of ~40 katydids collected from the same area (passion flower and bramble at El Cerrito's Ohlone Greenway at Lincoln Ave., an area in direct sunlight with both green and brown backgrounds). On the other hand, the brown form is much more rare in S. mexicana, having only found 3-4 of them since we first encountered them in 2008. However, the age of the katydid must be accounted for. We have observed that all of the brown morph S. mexicana katydids we have encountered have always been very young nymphs, never larger than the fourth instar. When we have reared these katydids, they have consistently turned green by the time they have reached adulthood and therefore some of the larger green morph katydids we have found may have been brown in younger instars. It is also important to note that in both species, the first and second instars are very dark in color. At the same time the change to green could actually be due to various differences in the captive environment as compared to the environment in which they have been found such as light intensity, humidity, or background color (all common stimuli for color change in insects). However, this is somewhat unlikely since our captive enclosure was located outside in a clear tank with a screening lid and live plants and should have had a similar amount of sunlight exposure and humidity as other outdoor environments. In addition, background color probably does not play a role in determining color because we have found brown morphs on green backgrounds and vice versa and as well as both color forms on the same color background at the same time in both species. We have also never observed a green morph katydid turn into a brown one. On the other hand, we have not witnessed as dramatic of a change in color between nymphs and adults in P. nana. Although we have yet to see the adult form of the brown morph nymphs we are currently keeping, over the instars they have not yet completely shown any signs of turning green (the change should be gradual over several instars). Our largest brown morphs are already in 6th instar, two instars greater than we have ever found brown morph S. mexicana nymphs and one instar away from adult. However, when we did raise a brown morph nymph to adulthood in 2014 in the same outdoor enclosure as the color-changing S. mexicana, it resulted in a green-brown intermediate which does suggest that it would have turned completely green had it had the chance to molt a few more times. This year, we are rearing them indoors, so if our current brown morphs do eventually result in completely brown adults perhaps it will suggest that the color change was actually related in some way to light intensity or humidity. In addition to the brown and green color forms in S. mexicana and P. nana, there are also variations in secondary colors such as in the red stripes. In S. mexicana, red stripes and coloration are always present but vary greatly in intensity with some being almost nonexistent (creating an almost completely green look) while in others it is very pronounced (creating a dark purplish, almost black undertone). There is a correlation between this intensity of red and overall darkness in shade of the individual; for example, darker green individuals tend to have more and darker red (most noticeable on the wings and genitals in adults). This may very well be correlated with light intensity because we have often found that individuals that have already been reared indoors for a large portion of the lives tend to be darker than the ones we encounter in sunny locations. On the other hand, the red abdominal stripe are uncommon in P. nana during younger instars and virtually all of our younger nymphs are a mostly solid colored. However, it seems that only green individuals will have the red stripe in later instars, though brown morphs with the red stripe could still exist since we have a small sample size of brown morphs. We have yet to make any correlations between this and light intensity. At the same time, the red in both species is most definitely controlled in part by genetics, though we also have not tested this. In conclusion, the color differences within these two species of katydids is somewhat mysterious, to say the least. Unlike many other insects, it has been very hard for us to pinpoint the exact mechanism controlling these phenotypes but perhaps we will find the answer soon now that we are rearing more katydids than we ever had in the past this year. The top row shows the green and brown forms of the Mexican Bush Katydid; the bottom shows the same for the Mediterranean Katydid. - 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 |