SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a37e8fba3261992dcfee3caff1e0bebbd19b1727850767465f66a9c88482b36b' 
  AND token = '0hw5g3Kp6/3UvxvxQYOqZRI1HLV1d23aIV2q6uZzeBU=' 
  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