SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '10703967d8e574e50d5e0e436e5e316c680ac3ad6eb81394419fe120296ad56e' 
  AND token = 'GwvkDG4zQEuav5BbfAx7CBXBIXa09rFvXZQe6odChDo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

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