Sthenelais boa has a limited distribution on the Belgian part of the North Sea: in both periods the species was only observed in the near-coastal zone, with the exception of the eastern coastal zone. Whereas S. boa was only found in low densities in the 1976-1986 period (maximum 12 ind./m2) densities up to 250 ind./m2 were recorded in the 1994-2001 period.
Degraer, S.; Wittoeck, J.; Appeltans, W.; Cooreman, K.; Deprez, T.; Hillewaert, H.; Hostens, K.; Mees, J.; Vanden Berghe, E.; Vincx, M. (2006). The macrobenthos atlas of the Belgian part of the North Sea. Belgian Science Policy. D/2005/1191/3. ISBN 90-810081-6-1. 164 pp. (look up in IMIS)