EVENTS

          Members Reports and Photos

SATURDAY AUGUST 1st 2015                                        PRAEGER CENTRE, NBGs

Moths and moth traps for beginners
Some of the current publications useful for the identificaton of both micro and macro moths were on display and useful websites were mentioned. A number of specimens which had been brought in a cooler were examined and returned later in the day to their habitats.
 
An Introduction to Potamogeton Species
A brief summary of documented pondweed studies, in particular those by Fryer, Dandy and Preston, was presented. A selection of pressed specimens was circulated to illustrate the variety within the Potamogeton genus. 

Fresh material was then examined and identified with the aid of the illustrations and descriptions in Pondweeds of Great Britain and Ireland (Preston, C.D., 1995). This material was used to illustrate the intraspecific variation in leaf size and shape due to environmental factors including rate of flow and depth of water. The distinguishing features of P. natans, P. polygonifolius and P. coloratus were exhibited. Next, the salient features of P. gramineus, P. lucens and P. perfoliatus were shown before turning attention to their three hybrids i.e. P. x zizii, P. x salicifolius and P. x nitens. Features of the parent plants inherited by the hybrids aided identification. A discussion of the establishment of Potamogeton hybrids ensued.  P. crispus was then examined before demonstrating two linear-leaved species, P. pectinatus and P. berchtoldii, and the dissection technique required to ensure correct identification of these species.   

Finally, techniques for the collection and preservation of Potamogeton specimens were explained.  

Margaret Norton 


 
Short Presentations
Euphrasia (Eyebrights) are a member of the Orobanchaceae family with a hooded upper petal. Currently a major project studying the genus is underway in Britain and Ireland. This project involves the collection of specimens, their curation and the analysis of their DNA. It is hoped that this project will through light on the species and their parasitized host plants.There has been, for a longtime, debate on what is a species and what is a hybrid within this family. Currently eleven 'taxa' are recognised in Ireland and approximately double this number in Britain. Members were introduced to a simple key for identification purposes and some of the more easily recognised species including Euphrasia anglica and E. salisburgensis. The latter species is confined to the limestone pavements of the west of Ireland and the nearest sites outside Ireland are in Vosges Mountains.

David Nash.

Waring                Manley             Sterling

     

Emmet & Heath            Skinner                   Goater    

         

       Brimstone                  Small Magpie              Common Wainscot 

     

BSBI Handbook  Potamogeton coloratus Fryer &t Bennet

   

          P. lucens                            P. lucens 

   

      P. coloratus                                        P. crispus                    P. crispus

     

 P. gramineus (with floating leaves)              P. gramineus                      P. gramineus

    

    P. natans                      P. natans

      

                      P. perfoliatus              P. perfoliatus                   P. x zizii                          

   

P. x nitens                              P. x salicfolius                          P. polygonifolius

 

P.pectinatus                     P. berchtoldii

 

Euphrasia nemorosa  Orobanche hederae

 

E. anglica                 E. salisburgensis

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 Photographs: © P Lenihan