SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '74462e6e22ca07f9e2253f3b0f4bb0c7a4cf51847d70a4506a9dca3affc06840' 
  AND token = 'C4nn3AgBEFg811Zi1vEaunpUkdqp/z7vlE4MG8S2shE=' 
  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