Species of the Month - August 2012

Forest Bug

Pentatoma rufipes

The Forest Bug is our commonest shieldbug, and is most plentiful in August, at least as an adult, as the larva turn into adults during July.  The adult can survive until November but is not often seen after mid-September.  The adult's work is done when it lays its eggs in August, and the larvae which hatch from these overwinter and continue to grow until the following July, when the cycle repeats.  The mostly feed on oak, also on alder and a variety of other trees and shrubs.

Pentatoma rufipes
Forest Bug
  Pentatoma rufipes
Forest Bug

The Forest Bug is identified by the orange spot on its back and the blunt projections or "shoulders" from the corners of the thorax.  Make sure it doesn't have sharp projections there, or you have the Spiny Shieldbug, a much rarer find, which I have only seen once in Argyll.  There's a photo of this below left, and you can report this species using the form as well.

Picromerus bidens
Spiny Shieldbug
  Piezodorus lituratus
Gorse Shieldbug

The Gorse Shieldbug also occurs locally, usually on Gorse or Broom, but the only photo of an adult that I have is this old one, above right.  The amount of red on it can vary, but note the broad scutellum tip (the part that forms the orange spot in the Forest Bug, green in the Gorse Bug).  This distinguishes it from the Birch Shieldbug.  Much better pics of the Gorse Bug at http://www.britishbugs.org.uk/heteroptera/Pentatomidae/piezodorus_lituratus.html

Birch Shieldbug

Here is the Birch Shieldbug, with a much narrower scutellum tip than the Gorse Bug.  Like that species, the proportions of red and green vary.

Rhacognathus punctatus, nymph
Heather Bug (nymph)

The only picture of the Heather Shieldbug I have is this nymph or larva.  The adult looks different (see http://www.britishbugs.org.uk/heteroptera/Pentatomidae/rhacognathus_punctatus.html ) but the yellow or red band on the legs is constant and is all you need to identify this bug.

Acanthosoma haemorrhoidale
Hawthorn Shieldbug

The Hawthorn Shieldbug showing how your shieldbug photography improves when you get a Lumix.  This is like the Birch Shieldbug but its "shoulders" stick out much further and are coloured red, often with a black tip.

Dolycoris baccarum
Sloe Bug

A special prize for anyone who finds the Sloe Bug.  I have never seen it, but Sallie took this photo recently at Tentsmuir on the east coast.  It is very rare this far north but may be lurking on the west coast somewhere.  It can be found on any kind of tall herb or shrub.

Help us gain more knowledge of the shieldbugs in our area.  Please send in your sightings using the form below.  If you are not sure of the identity of your shieldbug, please send a photo to sightings@lnhg.org.uk, or put one on the LORN forum and let me know it is there.

Date of sighting 
Grid reference 
Number seen 
Name of finder 
Your name (if different) 
Email (not needed if I already know it!) 
Any other details, e.g habitat, behaviour 


By filling in this form you agree that the information contained in this form may be collated and disseminated manually or electronically for environmental decision-making, education, research and other public benefit uses in accordance with the LNHG data access policy.  Your email address will not form part of the record and will not be passed on to anyone.

Carl Farmer
G Biological Records Manager

Sightings so far

6 Aug: Gordon Jack found this Hawthorn Shieldbug on an upturned flowerpot in his garden at Onich.  Photo by Sallie Jack.

Acanthosoma haemorrhoidale

Cynthia sent a record and photo of a Spiny Shieldbug found on Mull on 30th August 2008.  This is one of the few carnivorous species and it's particularly fond of big hairy caterpillars.  Photo by Cynthia Grindley.

Picromerus bidens

18 Aug: A Forest Bug was found in Dalavich Oakwood on the lnhg walk.

15 Sep: Gordon Jack found a Forest Bug caught in a spider's web on his porch door at Onich.

17 Sep: I found a Forest Bug at Armadale on Skye.

Note you can still send in records for past species of the month.  Here is the list of species we've had so far:

Jul 2012 - Grayling
Jun 2012 - Greater and Lesser Butterfly Orchids
May 2012 - Small Copper
Apr 2012 - Green Tiger Beetle
Mar 2012 - March Moth
Feb 2012 - Barren Strawberry
Jan 2012 - Brambling
Dec 2011 - Red Squirrel
Nov 2011 - Hazel Gloves
Oct 2011 - Small Tortoiseshell
Sep 2011 - Fly Agaric
Aug 2011 - Grass of Parnassus
Jul 2011 - Golden-ringed Dragonfly
Jun 2011 - 7-spot Ladybird
May 2011 - Green Hairstreak
Apr 2011 - Townhall Clock

Mar 2011 - Frogspawn

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All photos and other content copyright Carl Farmer except where stated