SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a4d36ca19fc4d71869f903938a22c0104fab8c5b80a8fccd19cae4e261901d71' 
  AND token = 'yO+qiXzZdYipognh6gx+p1rPzZbJbTikYGnpQ1c4YS4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

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