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Fringed orchid aphidOn this page: Identification & Distribution Other aphids on the same host
Identification & Distribution
Adult apterae of Cerataphis orchidearum (see two pictures below) are blackish or dark reddish brown, surrounded by a fringe of wax tendrils, and with the dorsum dusted with powdered wax. Antennae are fuscous, darkening gradually towards the apices, and legs are dusky with dark tarsi. The body is flat and circular with crenulated margins. The frons has two pointed processes or 'horns', shorter than second hind tarsal segment, and also filimentous frontal setae (cf. Cerataphis brasiliensis on palms, which has 2 thick, short, lance-shaped, frontal setae). The antennae are about 0.15 times as long as the body, and are 4- or 5-segmented. The rostrum reaches to the middle coxae. The apical rostral segment (RIV+V) is almost equal in length to the second hind tarsal segment (HTII) (cf. Cerataphis lataniae on coconut palms, which has RIV+V 0.67-0.75 times HTII). There are rather long, fine hairs on the head and body and around the siphuncular pores. The longest hairs are on tergite VIII, the cauda and the anal plate. These hairs are 0.6-0.8 times as long as the width of the siphuncular pores. The legs are very short, but the tarsi are not reduced. The siphuncular pores are distinct, placed on low cones. The cauda bears 10-16 hairs. The body length of adult Cerataphis orchidearum apterae is 1.0-1.7 mm.
Note: In the past this species has sometimes been confused with the palm aphid Cerataphis lataniae which, in turn, has been confused with another palm aphid, Cerataphis brasiliensis (albeit there are no reliable records of either from orchids). Early records of Cerataphis lataniae on orchids were probably Cerataphis orchidearum (and the latter is not recorded from palms).
First image above copyright Sharon Reid, all rights reserved;
Immature Cerataphis orchidearum (second picture below) are pale green with darker green markings, and look rather more 'aphid-like' than their adults, though still with a fringe of wax.
The alate (not pictured) has a yellowish abdomen. The frons lacks 'horns', and the antennae are about 0.4 times the body length. Antennal segment III is at most 1.25 times longer than segments IV and V combined. There are about 20-30 ringlike secondary rhinaria on antennal segment III, and 8-15 each on segments IV & V. The cauda has 10 hairs (rarely less). Siphuncular pores are present. The body is 1.6-2.3 mm long.
First image copyright Simbaqueba et al. (2014) under a Creative Commons Attribution License 4.0;
Cerataphis orchidearum is found on various types of orchids (Orchidaceae). Earlier records of Cerataphis lataniae from orchids are thought to refer to this species. It inhabits the leaves, and sometimes the flowers of various orchids. The sexual phase is not known in this aphid, and all populations appear to anholocyclic. Alates are very scarce. The fringed orchid aphid is widely distributed in the tropics, and in glasshouses in temperate climates.
Other aphids on the same host
Cerataphis orchidearum has been recorded on 2 Dendrobium species (Dendrobium gracilicaule, Dendrobium mutabile).
Cerataphis orchidearum has been recorded on 2 Epidendrum species (Epidendrum ramosum, Epidendrum secundum).
Damage and control
On orchids Cerataphis orchidearum are found feeding on the buds and flowers, and also on other succulent new and growing tissues such as the leaves, sheaths, and flower parts. Damage to the plants is due to repeated insertion and probing, as well as by nutrient removal. Feeding debilitates the plant and can cause generalized yellowing, and distorted leaves and flowers. As well as direct feeding damage, aphids may transmit plant viruses, although this is not thought to be a serious problem for orchids. A wide range of insecticides are available for aphid control but where conditions are manipulated, as in greenhouses, biological or integrated control offer better options. For more regarding aphid control on orchids see St Augustine Orchid Society.