23155_Peltigera:ascophyllum leaflet - Plantlife

BACK FROM THE BRINK MANAGEMENT SERIES Peltigera didactyla showing the circular soralia (powdery reproductive structures) © John DouglassOther dog-lichen species whichmay be confused with the Ear-lobedDog-lichenPeltigera didactyla has powdery granules indistinct circular patches, called soredia, thatform on the lobe surface.Peltigera praetextata is generally larger, withlobes up to 3cm in size and has small lobe-likeisidia mostly clustered along the lobe marginsor along the edges of splits on the uppersurface of the lobes.Peltigera membranacea is very common andforms wide radiating patches up to 40cmacross. The lobes are up to 3cm wide, aregrey when dry and brown when wet, and havea felt-like, ridged upper surface. The lowersurface is whitish with pale, raised veins anddispersed bottle-brush like rhizines.Peltigera britannica is occasional to rare, andcoloured bright green when wet and palebrownish-grey when dry. The lower surfacehas indistinct veins and the upper surface hassmall, dark, button-like cephalodia. These arestructures containing a cyanobacterialphotobiont, which is a different photobiont tothat of the thallus, or main body of the lichen.Peltigera hymenina is very common, forminglarge patches up to 20cm across with matt orshiny grey or brown lobes up to 2cm wide.The lower surface is cream or light brownwith flat veins and pale simple rhizines.4 Peltigera praetextata showing the plate likeisidia, which mainly develop along the edges ofthe lobes © John Douglass