First record of the tropical aphid Schoutedenia ralumensis (Hemiptera, Aphididae) from Cambodia, with a re-description of the oviparous females and DNA barcoding

<i>Schoutedeniaralumensis</i> is newly recorded from Cambodia on <i>Phyllanthus</i> sp. (Phyllanthaceae). The poorly-known morphology of oviparous females is re-described with live photographs, biometric measurements and photomicrographic illustrations. Additionally, DNA barcoding, based on mitochondrial cytochrome c oxidase (COI) sequences, was performed on the Cambodian specimen and compared with available sequences, including one of <i>S.emblica</i>. Additionally, we propose the synonymisation of <i>S.emblica</i> under <i>S.ralumensis</i> as a conspecific variant. These findings expand the known distribution of <i>S.ralumensis</i> and contribute to a better understanding of aphid diversity in Cambodia.