African Orthetrum species can be a nighmare. Such is the case with O. stemmale and O. brachiale which, according to Tarboton, “are only conclusively distinguished by the slight difference in male 2ary genitalia”. Except when you have an immature male, apparently; immature males of O. stemmale and O. julia have white appendages, according to the BDI but O. stemmale has doubled cells in the Rspl whereas O. julia does not.
All of which means, I’m pretty sure that this character from Livingstone, 2022, is correctly identified.
| immature male | |
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| male | |
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