Praying mantis, for example, belonging to religious group (6)
I believe the answer is:
insect
'praying mantis for example' is the definition.
(I know that Mantis religioso is a type of mantid)
'belonging to religious group' is the wordplay.
'belonging to' becomes 'in' (in can mean being a member of).
'religious group' becomes 'sect' (eg a religious sect).
'in'+'sect'='INSECT'
(Other definitions for insect that I've seen before include "Eg, beetle or bee" , "Small, usually winged, creature" , "A fly, for instance" , "Eg, ant" , "cricket, say" .)