SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f694f9767964d39f5b6a659b0037964c1886d315dbd2150513dee1c0db02a1ca' 
  AND token = 'lQizy90NNNma4+EEv5R/dwMY3gtrFm2mqeYaeShq7ug=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

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