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Paracletus [Fordini]Paracletus have 6-segmented antennae in all morphs; the primary rhinaria are not surrounded by rings of short hairs. Apterae have no secondary rhinaria, but alatae have numerous very small transverse oval or near-circular secondary rhinaria scattered on the underside of antennal segments III-VI. The wings of alatae are held roof-like in repose; the media vein of the forewing is unbranched, and cubital veins leave the main vein at the same point. The hind wing has two widely separated oblique veins. Wax gland plates are absent from all morphs. There are about four species known species in the genus Paracletus. Only Paracletus cimiciformis is known to complete the holocycle with galls on Pistacia. Sexuparae of Paracletus donisthorpei have been recorded from Pistacia terebinthus, but the gall-living generations of that species are so far unknown. Paracletus cimiciformis (Vampire pistachio-grass root aphid) Europe, Asia, North AfricaThe fundatrix of Paracletus cimiciformis induces a gall on its primary host, Pistachio (Pistacia spp.). The gall is a flat fold which develops from the leaf edge (see first picture below), retaining the original yellow-green colour of the leaf underside (cf. galls of Forda marginata on Pistacia, which turn bright red). The mature fundatrix (not pictured) in the gall is globose, yellow, with 6-segmented antennae, and a body length of about 1.5 mm. The second generation are all alatae which emerge from the gall in September-October. The alate vivipara of Paracletus cimiciformis (not pictured) has large, prominent black eyes. The antennae are about 0.4 times body length, and have an extremely short terminal process (cf. various Forda species and Smynthurodes betae, which all have the terminal process as long as, or longer than, its basal width). Secondary rhinaria are distributed 39-50 on antennal segment III, 22-40 on segment IV, and 7-17 on segment V. The thorax is darker than the abdomen, and the sides are pale yellowish. The legs are mainly brown, but the femora bases and to some extent tibiae bases are yellowish. There are no siphunculi. The body length of these alatae is 1.5-2.0 mm. These winged forms leave to found colonies, mainly of apterae, on their secondary hosts, the roots of many species of grasses (Poaceae, including Agrostis, Brachypodium, Dactylis, Festuca, Hordeum, Oryza, Poa, Polypogon, & Triticum).
First image reproduced by permission, copyright Nicolás Pérez, all rights reserved; On the secondary host, Paracletus cimiciformis has two alate morphs, the dispersive viviparae and sexuparae, plus two morphologically distinct wingless morphs. Apterae of the 'round morph' of Paracletus cimiciformis are coloured dusky-olive to apple-green (the second picture above appears to represent this morph). Apterae of the 'flat morph' of Paracletus cimiciformis are shining white or yellowish white (see third picture above). The body is flattened, especially the margins, with longitudinal dorsal rows of muscle sclerites, and a ventral grove between the middle coxae. The cuticle is reticulate with numerous short hairs. There are indentations on the posterior edge of the genital plate, and in front of the anal plate. The antennae are about 0.3 times as long as the body, and are 6-segmented. Antennal segment III is about 2-3 times as long as segment II, and 1.1-1.5 times segment IV. The rostrum reaches past the hind coxae. The legs are strongly built, the hind tibiae are curved and very long. The body length of these adult apterae is 2.4-3.5 mm. Paracletus cimiciformis is holocyclic in warm climates, and host alternates between Pistacia (most commonly Pistacia terebinthus) and the roots of grasses. Host alternation takes place over a two year cycle. The eggs on Pistacia hatch in spring of year 1, and the fundatrix induces a gall. Her offspring live and develop in the gall, all becoming alatae, which move to the roots of grasses in autumn. Winter of year 1 & spring of year 2 are spent in the soil as the two different apterous morphs - the round (domed) morph on the roots of grasses, tended by ants, and the flat morph mainly feeding on ant larvae within the ants' nest. These flat morphs produce alate viviparae, which fly to other grasses, and in the summer of year 2, they produce sexuparae which migrate to Pistacia and produce apterous males and oviparae in autumn year 2. The oviparae lay the eggs which hatch the following spring. Paracletus cimiciformis has been recorded from Pistacia in southern Europe, Iran, Israel, Malta and Turkey. Anholocyclic populations on the roots of grasses occur outside the range of the primary hosts throughout Europe, in north Africa and across Asia to Japan, Korea and China.
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