Key to the Palaearctic species groups of Botanophila (males).
1. Cercal plate extended in distal part into a long, undivided and narrow process, often reaching or even surpassing apices of surstyli, and without any submedian or lateral processes (Figs. 6–9) .............................. .......................................................................................... latifrons, varicolor, askoldica and salicis -groups ..................................................................................................................(also B. cuspidata and B. nupera)
– Cercal plate not as above, distal margin either narrowly split (partite), or divided into two diverging processes, or with two or three short processes, or short and cordiform ..........................................................2
2. Cercal plate long and narrowly separated in distal part, forming two closely approximated halves of a more or less pointed cercal plate; no subcercal structure present (Fig. 10) .................... brunneilinea -group
– Cercal plate not split in distal part into two closely approximated halves, or if so then a subcercal structure present, either hidden behind cercal plate or distinctly visible and bearing a median rod-like process...... 3
3. Cercal plate with a subcercal structure bearing a short or long rod-like median process (Figs. 11–14) ....... .................................................................................... gnava, cordifrons, bompadrei and maculipes -groups
– Cercal plate without subcercal structure...................................................................................................... 4
4. Cercal plate with 2 long submedian distal processes which reach almost to level of apices of surstyli, and are generally diverging; sternite 5 with separated tufts of setae (Fig. 15) ........................... seneciella -group
– Cercal plate without two long diverging processes on distal margin .......................................................... 5
5. Pregonite with two expanded (foliate) setae; cercal plate large in relation to surstyli, which have truncate distal margins in lateral view (Figs. 16, 16 a)........................................................................ helviana -group
– Pregonite with normal slender setae, or at most with slightly wide setae, cercal plate otherwise .............. 6
6. Cercal plate longer than width, with a bifurcate distal margin produced into two short blunt processes (further lateral marginal processes may be present) (Fig. 17) .................................................... depressa -group
– Cercal plate either simple (cordifrom) or not longer than width, or with three processes on distal margin 7
7. Cercal plate with three processes on distal margin (Fig. 18) ..................................................... fugax -group
– Cercal plate with two processes on distal margin, or none.......................................................................... 8
8. Cercal plate with two processes on distal margin (lateral or submedian) (Fig. 22) ............... dissecta -group
– Cercal plate without processes on distal margin.......................................................................................... 9
9. Surstyli slightly or strongly concave on posterior margin in lateral view, and with a small subapical tooth on inner margin (Fig. 20) (except B. kenji) .......................................................................... biciliaris -group
– Surstyli in lateral view not concave on posterior margin .......................................................................... 10
10. Surstyli bifurcate apically (Fig. 21) .............................................................................................. okai -group
– Surstyli simple (except B. cylindrica which has a median tooth on inner margin) (Fig. 19) striolata -group