Biology, images, analysis, design...
|"It has long been an axiom of mine that the little things are infinitely the most important" |
Woolly maple aphidOn this page: Identification & Distribution Other aphids on the same host Damage & Control
Identification & Distribution
The nymphs and apterous adults of Neoprociphilus aceris (see two images below) are orange-brown to purplish, and show varying degrees of wax formation. Most of the wax is on the posterior abdominal segments, which gives the tip of the abdomen a tufted appearance. Fundatrices of Neoprociphilus aceris (on the primary host) differ from subsequent apterae by having 5-segmented antennae, large wax plates on the head, and siphunculi. The resulting generations of adult apterae on the primary host can take two forms: Early in the season most are of the nymphoid form. The head is dark with small wax pore plates, and antennae are 6-segmented, with segment IV distinctly shorter than V. Each eye is reduced to an ocular tubercle bearing just 3 ommatidia (=triommatidium). The rostrum reaches to the mesocoxae. The abdomen has large wax plates on the sides. The siphunculi are small and porelike. The subalatoid form has eyes with few to many ommatidia surrounding the triommatidium. Antennal segment IV is about the same length of V. Wax pore plates on the abdomen are more distinct, with 6 rows on at least some of the abdominal segments I-VI, VII with 4 plates, and VIII with 1. Their siphunculi are porelike.
First image above copyright Erik Rebek, second image copyright Evan M. Raskin,
Alate Neoprociphilus aceris viviparae (see first picture below) have 2 conspicuous wax plates on the dorsum near the apical edge, which produce copious long tendrils of wax. The antennae are dark, with segment III bearing 4-9 oval to slightly elongate secondary rhinaria; the terminal process is less than 0.1 times as long as the base of segment VI. The mesothorax has large triangular wax plates on the dorsum. The wings are hyaline. The hind wings have the media vein and radius originating at a near-central point. The abdomen is pale and each segment bears 6 rows of large wax plates, except on abdominal segment VII which has 4, and VIII which has 1. The siphunculi are circular and porelike. The cauda has 3-4 hairs.
First image above copyright Josh Emm, second image copyright Jennifer Carr, University of Florida, Bugwood.org,
Apterous viviparae of Neoprociphilus aceris on the secondary host (Smilax) (see second picture below) have the eyes slightly stalked, and composed of 3 ommatidia. The antennae are dusky, and 6-segmented, and the rostrum reaches the first abdominal segment. The thorax is pale, and bears wax plates. The abdomen is also pale, and bears 6 wax plates on each segment, except VII which has 4, and VIII which has 1. The siphunculi are present as slightly raised pores, and the cauda has 4 hairs.
The woolly maple aphid's life history is described by Smith & Graham (1967). The eggs are deposited in the cracks or crevices of the bark on the trunk of sugar maple (Acer saccharum) trees. These hatch in the spring as soon as the buds begin to swell. The fundatrix gives birth to living young which mature into apterous viviparae. These give birth to a second generation of apterae which give birth to the alate migrants. These migrate to greenbrier (Smilax spp.), where they produce a minimum of 2 generations of apterous viviparae before the first winged sexuparae are produced in late August or early September. The sexuparae leave greenbrier and return to maple, where they deposit apterous oviparae and apterous males. These mate, and the oviparae produce eggs which overwinter. Some of the apterae remain on greenbrier, and in late autumn produce hibernating nymphs which overwinter in the first instar in rolled leaves and debris at the base of greenbrier. The species is, therefore, able to maintain itself continuously on greenbrier, as well as host alternate between sugar maple and greenbrier.
Neoprociphilus aceris occurs wherever Acer saccharum is grown in eastern North America.
Other aphids on the same host
Neoprociphilus aceris has been recorded on 1 maple species (Acer saccharum).
Neoprociphilus aceris has been recorded on 4 species of greenbrier (Smilax herbacea, Smilax lasioneura, Smilax rotundifolia, Smilax tamnoides). For all these 4 species of Smilax, Neoprociphilus aceris is the only species of aphid that has been found on them.
Damage and control
The woolly maple aphid does cause some damage to sugar maple. There is premature senescence of the leaves on twigs which supported developing colonies of the aphid in spring, as can be seen in the picture below.
image copyright Evan M. Raskin, under a creative common licence.
This sort of premature senescence usually results from the aphid injecting a toxin during feeding. Senecence causes the plant to mobilize nutrients for retrieval, which are otherwise unavailable to aphids.