New species of ptyctimous mites (Acari, Oribatida) from Borneo and Sumatra Niedbala, Wojciech Zootaxa 2008 1786 1 18 9RNM Niedbala, 1998 Niedbala 1998 [151,592,311,337] Arachnida Euphthiracaridae Acrotritia Animalia Sarcoptiformes 16 17 Arthropoda species sterigma  Length of prodorsum 242, length of notogaster 475. Chaetome of legs: I: 1-3-4(2)-5(1)-17(3) -1; II: 1-4-3(1)-4(1)-13(2)-1; III: 2-2-2(1)-3(1)-11(0)-1; IV: 2-1- 2-2(1)-10(0)-1. This species is known as yet only from Society Islands ( Niedbała 1998). It is similar to  Acrotritia divida( Mahunka, 1991)from Perak ( Malaysia) by distally forked lateral carinae of the prodorsum. However the shape of the lateral carinae in these two species is different. The superior branch of the carinae in  A. dividais shorter and separated from the principal trunk whereas the superior branch of  A. sterigmais longer and adjacent with the principal trunk.