SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7fe213683ef974386ae4134c2f788c3fa45766ccfe4f466d7d55b4ab7654816d' 
  AND token = 'gzZC1EwjONj++0fHOIL5JA30rG9OT//T9oQKu/XkZvI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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