SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b6288ccbc5c002afd2731a1018ce40bea9e6c1dcaec2287cd6d7c73f199e2b9d' 
  AND token = '7OsNgDJHqwyRa5HnKfk+I5VqBwui/YJ7T2Sc1WBp64w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

Explain
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Impossible WHERE noticed after reading const tables