{"id":309,"date":"2021-02-06T21:55:00","date_gmt":"2021-02-07T03:55:00","guid":{"rendered":"http:\/\/box2406.temp.domains\/~oecanthi\/?page_id=309"},"modified":"2026-05-05T06:18:30","modified_gmt":"2026-05-05T11:18:30","slug":"predators","status":"publish","type":"page","link":"https:\/\/oecanthinae.com\/?page_id=309","title":{"rendered":"Parasites, Predators, Etc"},"content":{"rendered":"\n

This page offers photos of other creatures that prey on or have interesting relationships with tree crickets.<\/strong><\/p>\n\n\n\n

This healthy looking female Forbes’ tree cricket is sleek and green. When she became dull yellow in color and her abdomen became grossly bloated, I thought perhaps she was ill from not being able to oviposit her eggs.<\/strong><\/p>\n\n\n\n

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After she died I put her in a small container, and some time later I discovered this horsehair worm also in the container. Her abdomen was no longer bloated.<\/strong><\/p>\n\n\n\n

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Grass-carrying wasps make their nest in spaces with a shallow entry. This nest of Isodontia mexicana<\/em> is on a shallow ledge of the top space of a roll open window. <\/strong><\/p>\n\n\n\n

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This is an adult Isodontia mexicana<\/em> which emerged from the pupa below.<\/strong><\/p>\n\n\n

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This is a young nymph of a Snowy tree cricket, Oecanthus fultoni. The parent of the above adult grass-carrying wasp put this tree cricket in a paralyzed and preserved state, to be available for any wasp larvae in the window ledge nest.<\/strong><\/p>\n\n\n

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The young tree cricket is on the far right of this photo. These are all the orthopterans found in that window nest — including coneheaded and meadow katydids and one tree cricket.<\/strong><\/p>\n\n\n

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Oethecoctonus oecanthi<\/em> is a very small wasp that parasitizes the eggs of tree crickets. This photo shows a fully developed wasp inside a tree cricket egg. Tree cricket eggs are 3-4mm in length, so these wasps are very small. Adult females are only 2.4mm long. How they manage to get their eggs inside a tree cricket egg that is 5mm from the surface of the stem is a mystery.<\/strong><\/p>\n\n\n

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For more info on these wasps: https:\/\/zenodo.org\/record\/24184#.YB6qNjGSmt9<\/a><\/figcaption><\/figure>\n<\/div>\n\n\n

This photo shows the head of a wasp inside a tree cricket egg. When I find these wasp carcasses, they are in stems with tree cricket eggs that should have emerged that prior season. Why these wasps never managed to leave the stem is a mystery.<\/strong><\/p>\n\n\n

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This is a fully developed wasp, which never left the tree cricket egg. Note the shape – a perfect match for a tree cricket egg.<\/strong><\/p>\n\n\n

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For info on the life cycle of another tree cricket egg parasitic wasp: Macrorileya oecanthi <\/em>(Ashmead, 1894)<\/p>\n\n\n\n

Published in:\u00a0Ashmead, W.H. Order Hymenoptera. (In Smith: |Catalogue of Insects of New Jersey|). JOURBOOK: Annual Report of the New Jersey State Board of Agriculture VOLUME: 27(Supplement) PAGES: 510-613. (1900).<\/p>\n\n\n\n

The abstract indicates the wasp emerged from the stem in November of the same year the tree cricket eggs were oviposited.<\/p>\n\n\n\n

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I often encounter mites inside stems that I have opened to inspect the status of the previous season’s tree cricket eggs. In this empty egg case, you can see yellow shadows of mites. As far as I know, they are not true predators and did not eat the tree cricket embryo, rather they take advantage of an available space in which to dwell.<\/strong><\/p>\n\n\n

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With a backlit view through a microscope, we get a better view of the profile on the mites.<\/strong><\/p>\n\n\n

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This video shows the movements of mites inside the empty tree cricket egg case.<\/strong><\/p>\n\n\n\n