Atriplex Orache

Dichotomous table for leafminers

Incl. Halimione, Obione.

On Atriplex and other halophytic Amaranthaceae live a number of Coleophora species, of which the larvae feed exclusively on the flowers and developing fruits. These species are not treated here.

1afleck mine => 2

1bmine full depth; larvae with distinct, chitinised head => 5

1cmine upper or (less commonly) lower-surface; larva a maggot => 16

1d galls, etc => Tables for all parasites per species

2ahole in the mine untidy, not exactly round; case helicoid: Apterona helicoidella

2bhole neatly rounded; case not helicoid (Coleophora spp.**) => 3

3a spathulate leaf case => 4

3btubular leaf case: Coleophora salinella

4a mouth angle 20-25°: Coleophora picardella

4b mouth angle ca 55°: Coleophora ortneri

5a larva without feet: Pseudophytobius acalloides

5b larva with thoracic feet and prolegs => 6

6a mine small of indefinite shape => 7

6b mine not unusually small, shape more or less constant => 9

7a larva: pinacula colourless (the bases of the setae themselves are black) : Cnephasia incertana

7b pinacula black => 8

8a larva: behind/below the anus a chitinous comb: Cnephasia asseclana

8b anal comb absent: Cnephasia stephensiana

9a mine in stem or midrib, rarely with extensions into the leaves: Scrobipalpa obsoletella

9b mine entirely in the leaves => 10

10acorridor, with “intestine-like” loops: Chrysoesthia drurella

10bblotch, with or without preceding corridor => 11

11a frass in a big black lump at the start of the blotch: Chrysoesthia sexguttella

11b frass distributed otherwise, less copious => 12

12a mine preceded by a corridor => 13

12ba more or less irregular blotch, without a preceding corridor => 14

13a corridor in one or more U-loops; older larvae free, among spun leaves: Scrobipalpa nitentella

13b corridor gently winding, no U-turns; larve mines all its life: Chrysoesthia atriplicella

14a larva mines from a silken tube; larva: prothoracic and anal plate green: Scrobipalpa atriplicella

14b no silken tube; prothoracic and anal plate brown or black => 15

15a larva: head and prothoracic plate light brown: Scrobipalpa instabilella

15b head and prothoracic plate black (mediterranean species): Scrobipalpa halymella

16aat the start of the initial mine (the larvae may change leave and start a new mine) one or more oval egg shells => 17

16bno egg shells at mine begin => 21

17amines only in the leaves; larvae may leave a mine and start a new one from the outside the leaf elsewhere => 18

17blarva mines both the leaf and the stem (that becomes transparant): Delia echinata

17cthe mines of Botanophila depressa are unsufficiently known

18aegg shell firm, ribbed, always single: Clanoneurum cimiciforme

18begg shell tender (empy eggs usually collapse), finely reticulate, always (?) in groups of 3-6 => 19

19alowest tooth of larval mandible exceptionally large: Pegomya cunicularia

19blowest tooth not that oversized => 20

20alarva: angle between terminal and subterminal tooth of the mandible almost 90°: Pegomya betae

20bthis angle quite sharp: Pegomya hyoscyami

21a mine a corridor with strands of frass at either side => 22

21bmine different => 23

22a corridor pinnately branched: Liriomyza strigata

22b corridor irregularly, if at all, branched: Liriomyza bryoniae

23amine a corridor from start to end; frass in isolated grains: Chromatomyia horticola

23bmines blotch-like, sometimes with offshoots or an initial corridor => 24

24afrass in wide green zones at the end of offshoots of the blotch (often only visible after the upper epidermis has been taken away): Scaptomyza graminum

24bfrass very sparingly, in fine grains: Amauromyza flavifrons

Not included in the key: Chrysoesthia gaditella (mine not described), halimoniella; Coleophora atriplicis, sternipennella, versurella; Scrobipalpa halimioniella, halymella, ocellatella, salinella (improbable).

mod 9.x.2017