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Aphidinae : Macrosiphini : Cavariella araliae
 

 

Cavariella araliae

Chinese angelica aphid

On this page: Identification & Distribution Other aphids on the same host

Identification & Distribution

Adult apterae of Cavariella araliae (see first picture below) are pale yellow or pale green. They have red eyes and pale appendages, apart from the last antennal segment and tarsi which are dusky. The siphunculi and cauda are also pale. The body is oval in shape. The eyes and ocular tubercles are rather small, and antennal tubercles are not developed. The antennae are short, about 0.4 times body length, slender, and 5-segmented. The terminal process is about 1.7 times the base of antennal segment V. Antennal segment III is without secondary rhinaria. The rostrum reaches beyond the middle coxae. The body is without marginal tubercles. The siphunculi are imbricated, slender, reaching a little beyond the caudal apex, and somewhat dilated on the distal portion. The prominent supracaudal process is a little shorter than the siphunculi, but protrudes a little beyond them, and beyond the cauda. The cauda is wedge-shaped and broad, with 2 slight constrictions, and 2 pairs of lateral hairs present. The body length of adult Cavariella araliae apterae is 1.3-2.1 mm.

First image above copyright Onidiras; second image copyright CBG group;
both under a Creative Commons License.

The alate Cavariella araliae has dark, short, 5-segmented antennae. Antennal segment III has about 30 mostly large, round secondary rhinaria scattered over the whole length. There are broad dark crossbands on tergites II-VII, as well as large marginal sclerites. The siphunculi are slender, a little shorter than the last antennal segment, 2.5 times as long as the supracaudal process, almost reaching the caudal apex, roughly imbricated, and moderately dilated on the distal half. The supracaudal process is almost as long as antennal segment IV.

Takahashi (1921,1923) originally described the species in Taiwan on what is presumed to be one of its secondary hosts, angelica tree Aralia spinosa (actually Aralia elata?) - but it also occurs on other Aralia species. The under surfaces of the tender leaves are attacked. The greatest abundance seems to occur from January to March, but numbers are reduced at other seasons. Winged viviparous females are very rare. Salix is assumed to be the primary host, but no fundatrices or sexual morphs are known. Populations, initially described by Takahashi (1923) as Cavariella neocapreae but subsequently identified as Cavariella araliae, have been found on a potential primary host, Salix warburgii. However, they were overwintering anholocyclically along the midribs of the leaves. Alternatively a similar species in India, Cavariella biswasi on Salix elegans, may be Cavariella araliae on its primary host. The Chinese angelica aphid is distributed over China, Taiwan, Vietnam, Japan and Korea, to east Siberia.

 

Other aphids on the same host

Possible primary host

Cavariella araliae has been recorded on 1 willow species (Salix warburgii = Salix mesnyi).

Secondary hosts

Cavariella araliae has been recorded on 7 Aralia species (Aralia armata, Aralia chinensis, Aralia continentalis, Aralia cordata, Aralia elata, Aralia spinosa, Aralia thomsoni). There are also records from several other Araliaceae (Schefflera heptaphylla, Schefflera lutchuensis (?), Dendropanax arboreus, Tetrapanax papyrifer). Plus unconfirmed records from Torilis japonica and Broussonettia kazinoki.

Acknowledgements

We are grateful to Onidiras and CBG group for making their images of Cavariella araliae available for use under a creative commons licence.

We have used the accounts given by Takahashi, 1921 and Takahashi, 1923 together with information from Roger Blackman & Victor Eastop in Aphids on Worlds Plants. We fully acknowledge these authors and those listed in the reference sections as the source for the (summarized) taxonomic information we have presented. Any errors in information are ours alone, and we would be very grateful for any corrections. For assistance on the terms used for aphid morphology we suggest the figure provided by Blackman & Eastop (2006).

Useful weblinks

References

  • Takahashi, R. (1921). Aphididae of Formosa Part 1. Report of the Department of Agriculture Government Research Institute Formosa 20 p. 36, 37 Full text

  • Takahashi, R. (1923). Aphididae of Formosa Part 2 Report of the Department of Agriculture Government Research Institute Formosa 4, 1-97 (pp. 35,93) Full text