Species of the Month November 2022

Odiellus spinosus

Odiellus spinosus is a chunky harvestman which prefers man-made habitats and can often be found in gardens. Adults emerge during summer but can be found throughout autumn, particularly during mild years. It is a ground dweller but can often be seen resting on walls, fences and trees. 

Harvestmen can be a difficult group for beginners to identify, however Odiellus spinosus is relatively distintive. The body is larger than most species (male to 6.5 to 8mm, female 7 to 11mm) and it has short to medium length legs. The markings on the back (known as a "saddle", circled in green on the below image) is dark, and straight edged at the rear. The spiked structure at the front (known as the "trident", circled in red below) consists of 3 forward facing prongs. If you are unsure of your species identification, you can contact SEWBReC with photos to confirm.

More photos and information about Odiellus spinosus is available on NatureSpot, Eakring Birds and Spider Recording Scheme websites. There is also a very useful FSC Identikit key to Harvestmen available here.

Odiellus spinosus very likely to be found in gardens throughout south east Wales, particularly at low altitudes. However, like all harvestmen, it is very under recorded with just 46 records held at SEWBReC. You can view the 1km distribution for SEWBReC here and the 10km Wales wide distribution here.

If you spot Odiellus spinosus during November (or at any other time of year), please send us the record, ideally via SEWBReCORD or the LERC Wales App. Instructions on how to submit records are available here.