Sunday, 30 August 2015

Woolly Fringe-moss - Racomitrium lanuginosum

Found on Dartmoor this common species is quite forward to identify. Under the microscope the long wavy cells identify the group as Racomitrium. Grimmia also has wavy cells but these are short. Racomitrium lanuginosum has 90 degree projections on the white hair point which is visible with a high powered magnifying glass.

Racomitrium lanuginosum

Racomitrium lanuginosum long wavy cells

Racomitrium lanuginosum close up of hair point

Tuesday, 25 August 2015

Cerastium pumilum - Dwarf Mouse-ear

Cerastium pumilum and Cerastium semidecandrum are similar with the bracts being the best feature to separate the two. C. pumilum has a narrow translucent border and C. semidecandrum has a much larger translucent area.

Cerastium pumilum

Cerastium pumilum bract

Polygonum aviculare - Knotgrass

I found this plant today which I knew was Knotgrass but thought it would be fun to find out which. As it turned out it was rather more difficult than I imagined. It was the key in Stace that got me to the conclusion in the end by the 3mm length of the achene (dry fruit of a flowering plant). There was a mention of silvery sheaths later turning brownish in Domino Guides which I could see. Polygonum arenastrum (Equal-leaved Knotgrass) is the one I had most trouble with. P.arenastrum is said to have leaves on the stem and branches roughly the same but the leaves on the stem were different sizes making this feature difficult to determine. Maximum size of achene on P.arenastrum is said to be 2.5mm therefore not my plant.

Polygonum aviculare achene 3mm in length

Polygonum aviculare

Monday, 10 August 2015

Bilimbia lobulata

This is a lichen I re-examined and after several hours was glad I did as the outcome turned out to be different from the first. Description wise it's a granular thallus with black .75mm lecideine apothecia that are merging to create larger looking apothecia. It's growing on the top side of a brick wall. If you remove some of the lichen you can see that the underside is white. An apothecia section reveals 3-septate ascospores measuring 15µm x 4µm (too small for sabuletorum). The hymenium is brown measuring up to 90µm in height.

Bilimbia lobulata

Cystiphora sonchi

This gall was found on a basal rosette of Sonchus in a coastal dune at Wall Common, Somerset. The galls are very distinctive and examining through the microscope I could see the little diptera larvae.

Cystiphora sonchi larva

Cystiphora sonchi gall

Wednesday, 5 August 2015

Charmouth 1st August

I spent the morning near Charmouth looking for some local specialities namely Slender Centaury, Cliff Tiger Beetle and Sea Heath. To my delight I managed to find all three and some additions too. Being a beginner I found the Centaury group a little tricky to get the hand of but pointers that helped included looking for the presence of a basal rosette, whether the branches along the whole stem or just the top half and the leaf shape.

Lesser Centaury

Sea Heath

Slender Centaury

Asaphidion pallipes

Cliff Tiger Beetle

Stagonospora atriplicis