SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '74cb8107d251c1dfe4721073320f9f6f2aa1b16567adeef70f481613b0a2e98b' 
  AND token = 'k5+wn42eWO5Pm0oQeZRi2a9KiC2MJ3/MF20IS2pkHpM=' 
  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