Aphid key

Identification of aphids associated with Fagaceae

Simplified keys are provided to help you identify frequent aphid species:

  • Visual identification: from photos
  • Identification key: based on morphological criteria

Visual identification

Lachnus roboris, Lachnus pallipes

large aphid, dark brown, cornicles dark, reduced to a raised pore, alate with broad pigmented spots on wings

Myzocallis castanicola

light yellow to intense yellow, alates with pigmented abdominal spots distributed in pairs

Phyllaphis fagi

woolly beech aphid, colony covered with a mass of white woolly wax

Phylloxera spp

small aphid orangey yellow, colonies often distributed in a circle on underside of leaves

Stomaphis quercus

dark aphid, cornicles dark and reduced to a raised pore, characterized by very long rostrum

    

   

    

ici photo d'une autre espèce avec les mêmes caractéristiques : Stomaphis graffii inféodé aux Acer

Thelaxes dryophila, Thelaxes suberi

aphid brown or greenish with longitudinal line lighter, alate bears wings kept flat 

Tuberculatus annulatus

yellow or greenish aphid, cornicles short with length same as breadth,  3 pairs of dorsal tubercles, 3rd pair distinctive in size and pigmentation

Tuberculatus borealis

aphid yellow or greenish, cornicles short length same as breadth, presence of 4 pairs of corsal tubercles 

Tuberculatus querceus

aphid greenish to yellow, cornicles short and abdomen topped with a large dark bifid tubercle 

Identification key

Sweet chestnut

 

Large aphid (more than 3.5 mm), dark brown, living on branches
Apterous with antennae short, cauda shorter, cornicles short reduced to a raised pore;  alate with broad pigmented spots on forewing membrane
Lachnus roboris

               

 

Smaller aphid, light to intense yellow, living at surface of leaves or on young shoots; all the adults are winged and characterized by pigmented abdominal spots 
Larva and nymph yellow, abdomen with pigmented spots topped with long capitate hairs; cornicles small, cauda knobbed and anal patch bilobed; alate with dark dorsal spots distributed in pairs and marginal sclerites distinctly pigmented; head and thorax marked with a dark longitudinal medial stripe, cornicles small, dark, wing veins with ends pigmented
Myzocallis castanicola

Beech

Large aphid (more than 3.5 mm), dark brown, living on branches

Apterous with antennae short, cauda shorter; cornicles short and reduced to a raised pore; alate with broad pigmented spots on forewing membrane
Lachnus pallipes

               

 

Green to pale yellow aphid, in colony covered with white woolly wax 
Apterous with elongate shape, antennae shorter than body, cornicles pore-like; alate pale with or without slight marks, antennae same length as body with processus terminalis very short, cornicles pore-like, cauda knobbed
Phyllaphis fagi

Oak

1

Large aphid (more than 3.5 mm), dark brown, living on branches
Apterous with antennae short, cauda shorter, cornicles short and reduced to a raised pore; alate with broad pigmented spots on forewing membrane
Lachnus roboris or L.pallipes

               

Smaller aphid

---> 2     

2

Chestnut or greenish aphid, flattened, with abdomen showing lighter-coloured longitudinal line 

Apterous with antennae short, consisting of 5 segments: cornicles reduced to a pore, cauda knobbed; alate shows antennae with 5 segments; hind part of abdomen with pigmented stripes, cornicles encircled with brown ring, cauda knobbed, wings kept flat with  medial vein only once-branched and wing veins strongly marked
Thelaxes dryophila

Wingless aphid with different uniform colour (green, yellow or orangey)

---> 3    

3

Tiny aphid (0.7-0.85 mm) orangey yellow, colonies often organized in a circle on the underside of leaves
Apterous with head and thorax globular followed by a triangular abdomen, genus characterized by 3 antennal segments, no cornicles, nor cauda; alate triangular, 3 antennal segments, neither cornicles nor cauda
Phylloxera spp

Medium-sized aphid, green or yellow, all adults winged

---> 4

4

Light to deep yellow aphid, characterized by pigmented abdominal spots distributed in pairs
Larva and nymph yellow, abdomen bears pigmented spots topped with long capitate hairs, small cornicles, cauda knobbed and bilobed anal patch; alate with dark dorsal spots distributed in pairs and pigmented marginal sclerites; head and thorax marked with a dark longitudinal medial stripe, cornicles dark, wing veins with ends pigmented
Myzocallis castanicola

Green to greenish aphid, or uniform yellowish 

---> 5

5

Larva and nymph green or yellow, antennae dark brownish at articular suturesalate with antennae dark brownish at articular sutures, abdomen characterized by the presence of 3 pairs of tubercles, 3rd pair larger and pigmented, cornicles short and black on distal half, cauda knobbed on a bilobed anal patch Tuberculatus annulatus

Larva and nymph green or yellow, antennae dark brownish at articular sutures; alate with antennae dark brownish at articular sutures, abdomen characterized by presence of 4 pairs of tubercles (first 3 pairs of same size and 4th pair often smaller), cornicles short with tip black, cauda knobbed on bilobed anal patch
 Tuberculatus borealis

Modification date : 07 February 2023 | Publication date : 15 November 2016 | Redactor : Evelyne Turpeau, Maurice Hullé, Bernard Chaubet