Arrhenatherum, false oat-grass

fam. Poaceae

1a mine full depth; larva with feet and chinitinised head; pupation outside the mine (Elachista) => 2

1b mine upper-surface; larva a maggot; pupation within or outside the mine => 3

1c galls, etc => 100

2a of too many Elachista‘s the mines and larvae are badly known, and a key cannot be made. According to literature the following species occru on this hostplant: Elachista albifrontella, apicipunctella, bedellella, canapennella, maculicerusella, nobilella, pullicomella, rufocinerea, subalbidella

3a larva: mandible with 1 tooth; rear spiraculum drawn into a slender point: Hydrellia griseola

3b mandible with 2 or more teeth; rear spiraculum not pointed (Agromyzidae) => 4

4a larve: cephalic skeleton of Agromyzinae-type; pupation outside the mine ** => 5

4b cephalic skeleton of Phytomyzinae-type; pupation within or outside the mine => 8

5a larva: behind the mandibles ventrally a field with spinulose warts; mandbie with 2-3 teeth => 6

5b no such field; mandible with 4 teeth (only occasionally on this hostplant): Agromya albipennis

6a larva: mandible with 3 teeth (the basal one clearly smaller than the apical two): Agromyza nigrociliata

6b mandible with 2 teeth => 7

7a larva solitary; rear end of blunt: Agromyza rondensis

7b larvae communal; rear end of cut off obliquely: Agromyza nigrella / A. mobilis

8a puparium in the mine => 9

8b pupation outside the mine => 11

9a puparium metallic black; spiracula not penetrating the epidermis: Cerodontha pygmaea

9b puparium orange-brown; front spiracula penetrating => 10

10a puparium monochromous; front spiracula somewhat bifid: Chromatomyia nigra

10b puparium with a ventral dark length band; front spiraculum fist-shaped: Chromatomyia fuscula

11a larva: rear spiraculum with 3 papillae: Liriomyza flaveola

11b rear spiraculum with 5-11 papillae => 12

12a larva: rear spiraculum with 5-7 papillae; October: Liriomyza pusio

12b rear spiraculum with 6-8 papillae; April-September: Liriomyza phryne

12c rear spiraculum with 9-11 papillae; May-September (occurrence on this plant not quite certain): Liriomyza graminivora

100a Nematoda => 101

100b Acari => 102

100c Coleoptera => 103

100e Diptera => 104

100f Hemiptera => 105

100d Hymenoptera => 106

100g rust fungi => 107

100h smut fungi => 108

100i powdery and downy mildews => 109

100j other causers => 110

101 – Nematoda

101a Anguinidae: Ditylenchus dipsaci; Subanguina radicicola

102 – Acari

102a Eriophyidae: Abacarus hystrix; Aculodes dubius

104 – Diptera

104a Cecidomyiidae: Contarinia arrhenatheri; Haplodiposis marginata

104b Chloropidae: Oscinella frit

105 – Hemiptera

105a Aphididae: Laingia psammae

106 – Hymenoptera

106a Eurytomidae: Tetramesa matrana

107 – rust fungi

107a Pucciniaceae: Puccinia arrhenatheri, arrhenathericola, coronata, graminis, striiformis

108 – smut fungi

108a Georgefischeriaceae: Jamesdicksonia dactylidis

108b Tilletiaceae: Tilletia caries, controversa

108bc Urocystidaceae: Urocystis avenae-elatioris

108d Ustilaginaceae: Tranzscheliella hypodytes; Ustilago avenae, hordei, striiformis

108e Ustilentylomataceae: Ustilentyloma brefeldii

109 – powdery and downy mildews

109a Erysiphaceae: Blumeria graminis

109b Peronosporaceae: Sclerophthora macrospora

110 – other causers

110a Fungi, Clavicipitaceae: Claviceps purpurea

110b Fungi, Dothideomycetes: Dilophospora alopecuri

** See also the key to grass-inhabiting Agromyza-larvae.

Not included in the key: Pseudonapomyza atra.

09/01/2017