SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '64be17ef9a22cc20163cfa2801697226c0801febdd49384e6494411e809d29da' 
  AND token = '2ieils5fBQJ+vIPnFDFSDCiUs2E6xjcjetW72ndC/ps=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}