SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0edfdb9674fff865d84c90397013ad8d37dc2b3dcdb39d5f9b8f1394fdb3a551' 
  AND token = 'V6eJFWJkbd5WgzPeUphGV7tjKdsOSW9gfyJLXMTXMmo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}