Hi Sturat, A.nijsseni are not too easy to sex early on. As they grow look for an increase in size in the side spot for a female and a decrease for a male. As to the gill plate makings, in the male it should not get too large and should remain as a line. In the females it will increase in size to a blotch covering the gill cover. Hope this helps. What other Apistos (& other dwarfs) were offered for sale at the YAF? I have noticed a pleasing increase in the number of fish available recently. At present I have nijsseni and panduro but others I have seen for sale (or obtained by aquaintances) are: A.cacatuoides A. norberti A. sp emerald A. sp aff geisleri A.hoignei A.trifasciata Nannochromis transvestitus N.parilus (sols as nudiceps) regards, Ken - Edinburgh. ***************************** Ken Laidlaw Royal Observatory, Edinburgh Web: http://www.roe.ac.uk *****************************