(248 BAsch) Ballistura schoetti (Dalla Torre, 1895)

*litoralis (Schött, 1893) [not (Moniez, 1890)]

Ballistura schoetti is moderately common and is probably widespread although there are no records from Wales or southwest England. This species is usually found in rotting seaweed, or inland in sites with high levels of organic matter including sewage treatment works. Ballistura schoetti is dark blue in colour, has 8+8 ocelli (Fig. 1) and reaches a length of 1.7 mm.  Popativ describes it as being distinctive given adequate inspection of the manubrium/dens, as the dens is cylindrical with a regular covering of hairs along its length on all sides  (Fig. 2). By contrast here are no ventral manubrial setae. Unfortunately, the few specimens in the NHML slide collection are in bad condition, hence the poor quality of the photographs below.

 

 

 

Fig.1: Ballistura schoetti collected from Mortyclough, Clare, Ireland in July 1960 by Peter Lawrence showing eight ocelli in the eye(*) and the oval post-antennal organ (PAO).

Fig. 2: Ventral side of the dens of Ballistura schoetti collected from Mortyclough, Clare, Ireland in July 1960 by Peter Lawrence. Note the numerous setae throughout almost the entire length of the dens.

 
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