SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a207b1ce9bfb9e4bc6d70dbd9ce96cbde72913c38a6f8cbae68ce94d4b79232f' 
  AND token = 'maSSjvtZaJxqjJ7GSasr62EH6i7M66M2a8L4IqpcS4Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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