SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a1d2a31c5138602bf7a9c3c6e4e2f63a35788550f621c9785b2a32e386e32ee6' 
  AND token = '528l2+UB1v8uR3Gn/SNqV1NMsSVEpfC+mKrU9U2+hvU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

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