Platybunus pinetorum is a rather striking harvestman with a very dark body, which in the females is complemented by a sharply pale-lined saddle. The ocularium is extremely large and robust - much wider than it is long - with a very deep central furrow. Each side of the ocularium is furnished with a number of stout tubercles. Another very distinctive feature of adults are the white, dagger-like, tubercles of the underside of the palpal femurs which are as long as the femurs are thick. In juveniles, the size of the ocularium is really huge relative to the body.
Because of the similar ocularium, there is some potential to confuse this species with Platybunus triangularis. But Platybunus pinetorum is generally a much darker animal and the ocularium even wider, relative to its length, and the central furrow deeper and wider, than that of Platybunus triangularis. In Platybunus triangularis the furrow in the ocularium narrows towards the front much more than in Platybunus pinetorum. The tubercles on the underside of the palpal femurs of Platybunus pinetorum are relatively larger than those of Platybunus triangularis. According to Wijnhoven (2009), juveniles of the two species cannot be told apart.
Platybunus pinetorum was first recorded in the UK in 2010 and has occurred in scattered locations from Northampton, through Yorkshire to Southern Scotland - see the distribution map of the Spider and Harvestman Recording Scheme . Winjoven (2009) describes the European population as 'European montane' but notes that the distribution is changing - possibly spreading north.
Platybunus pinetorum can be found on low vegetation but also in the ground layer. Juveniles tend to occur in the ground and herb layers. The habitats are varied - in the UK it is apparently synanthropic.
This is an exceptionally early species, with adults found in the UK between March and May.
Richards, P. 2017. Tabular key for Identification of British Harvestmen (Opiliones). Unpublished.
Wijnhoven, H. 2009. De Nederlandse hooiwagens (Opiliones). Nederlandse Entomologische Vereniging.