SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a82c2c8db6622c01ab885f398c24e63fdb38bffd1291f408db9b60dfd273ad4b' 
  AND token = 'e4o9g2/DpYlesb5FstRR9T3LrXvmYIby9wTo0vc/hFQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

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