SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c2da871392961bc2339c4c6fe684a92259571b2cd01bf0bf4110decd3399d385' 
  AND token = 'WcejrLTKzrUt+7QZfmDZElpxi+cpEhZbVDr6kGq35XQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

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