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The Mindarinae is a small subfamily with nine or more surviving species in one genus (Mindarus). They are all conifer-feeding, mainly on species of fir (Abies) or spruce (Picea). The fundatrices produce the sexuparae the same year. The sexuparae first appear just after bud break, as the new needles begin to expand. These aphids will take sap from the soft, current-year needles for three to four weeks until they mature (see picture below). This can cause appreciable damage to tree foliage. Colonies of Mindarus aphids are covered in waxy secretions (see picture below).
Mindarus abietinus sexuparae.
Four species are found in the Nearctic (North and Central America) and four or more in the Palaearctic (Europe, Asia). Mindarinae are generally considered to have the most 'primitive' features among extant aphids.
Adult Mindarinae viviparae may be apterous or alate. The eyes in early larval stages, and often also of the adult aptera, consist only of a triommatidium. The rostrum is retractable into the long first segment; the second segment is without wishbone-shaped stiffening, and last two segments are fused. The apterae have the head and pronotum fused. The empodial setae are hair-like, and the first tarsal segments have no dorsal setae. They have well-developed wax glands. The siphunculi are reduced to small siphuncular pores sited on cones. These are sometimes absent in the apterous morph. The cauda of the aptera is very small, crescent-shaped, with only 2 setae. The anal plate is entire or weakly indented; in the alate morph it is sclerotic.
Mindarus abietinus aptera dorsal, in alcohol.
The Mindarinae alate has the stigma in the fore wing pointed and extending to the very apex of the wing (see picture below). The radial sector vein separates from the main vein at the proximal end of the stigma, and the costal cell is widened. The epicranial suture is undeveloped, and on the pronotum sclerotization is split medially leaving a membranous zone. The cauda in the alate morph is triangular and the anal plate is sclerotic.
Mindarus abietinus alate on Abies (fir)
Both oviparae and males are apterous, mostly very small. The ovipara has subsiphuncular wax gland plates.
Genus Mindarus [Mindarini]
Wingless forms have a fused head and pronotum and well well-developed wax glands which produce a covering of wax wool. The antennae are short. The siphunculi are pore-like and the cauda is bluntly triangular. Winged forms have forewings with an elongate pterostigma, tapering to a point at the wing apex. Oviparae and males are wingless and reduced in size.
There are 8 or more species worldwide feeding on the growing tips and young cones of spruces or firs. They have a sexual stage in the life cycle, but there is no host alternation and aphids are not attended by ants.