SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1fd27863c743e6f19bf33bef3a791705983f3c4a887ffc2d42e0a7c13a127c0c' 
  AND token = 'a6FZ3uqp5nNxD1WEAquWSLbrs9JsHMP2C/66Us7fUXc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00009

JSON explain

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