SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3524c38de1055f63e409a4d548f710d28c215e0b7061a01a6918c673419fd305' 
  AND token = 'A2dBSEizIl6HyLV0vCKMcKCFL3P/74IVDfhNR0uedZM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

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