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Aloephagus aphidsOn this page: Aloephagus mysersi
The Aloephagus genus has only one species of aphid, namely Aloephagus myersi. The genus is characterised by the absence of siphunculi, short 5-segmented antennae and an elongate rostrum. Aloe species are thought to be the secondary hosts, since what is thought to be the alate of Aloephagus myersi was reared from galls on Pistacia.
Aloephagus are mainly found on Aloe spp., but have also been recorded on the related succulents Haworthia and Astroloba. They are thought to be native to Africa, but now have a cosmopolitan distribution.
Aloephagus myersi (Aloe vera aphid) Cosmopolitan
Adult apterae of Aloephagus myersi have an oval body, and are coloured orange-brown or dull-green (see first two pictures below). There is a covering of whitish flocculent wax, but it is not usually thick enough to hide the body color. Their antennae are 5-segmented, with the terminal process 0.25-0.4 times as long as the base. The head has two small wax glands on the vertex. The eyes are small and 3-faceted. The rostrum is elongate, reaching to or beyond the tip of the abdomen (but it may be retracted as in the clarified mount, third picture below, and appear much shorter). There are rounded marginal tubercles on the prothorax and abdominal segments I-VI, and very small wax glands of the Melaphis-type behind each tubercle. The dorsum is sparsely covered with short spines arranged in transverse rows on the abdominal segments. The trochanter is completely fused to the femur. Siphunculi are absent. The subgenital plate is bilobed, and conceals the broadly rounded cauda. The body length of adult Aloephagus myersi apterae is 1.8-2.5 mm.
First two images copyright Jeffrey W. Lotz, Florida Department of Agriculture and Consumer Services, Bugwood.org;
The alate of Aloephagus myersi (not pictured) has a black head and thorax. There are sclerotic bars on tergites VII & VIII and rather large marginal sclerites. The antennae are black and about 0.22 times the body length . There is an extremely large elongated primary rhinarium on segment IV which is nearly half as long as the segment, a round primary rhinarium on segment V, the normal cluster of secondary rhinaria and a short tubular terminal process. The rostrum is extremely long, reaching to the end of the abdomen. Siphunculi are absent.
Aloephagus myersi is only known from its secondary host, Aloe species. Their primary host is presumed to be Pistacia in Africa, as emigrant alatae suspected to be this species have been collected from galls on Pistacia aethiopica in Kenya. Populations outside Africa are anholocyclic. On Aloe they live under the leaf bases, attended by ants. Aloephagus myersi has also been reported from the related plant genera Haworthia and Astroloba. It is thought to be native to Africa where it is widespread south of the Sahara, but is now found worldwide, in glasshouses in temperate climates, and can be a major pest.