CLADOENDESIS OF EPHEMEROPTERA
Figs 2329. Indobaetis costai. 2325 male imago: 23 wing; 24 genitals (ventral view, muscles of middle and left parts shown by interrupted lines); 25 head and dorsal outline of pronotum and anteronotal protuberance, lateral view. 26 head of female imago, dorsal view. 27 subimaginal exuviae of right unistyliger and gonostylus; 28 subimaginal genitals developing under larval cuticle; 29 the same at earlier phase.
Abbreviations: gs1gs3 1st3rd segments of gonostylus; m.s
median sterno-styligeral muscle; m.IXX intersegmental ventral muscles going from base of 9th abdominal segment to base of 10th abdominal
segment; us unistyliger.