SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'baef795d670170e5a71f1796995d8fa35bd5759c05fb15f44ae244f04f7b7411' 
  AND token = 'UJbvyM+68fdxEwCCajX7KlU336tA6hhhp22nw3oGjxc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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