SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2d279285258df8169cabebae848f03288b65189e89ca37c429680c882cee5f4b' 
  AND token = 'WN87NEgf85Xnpyx3LZy79kNsvbVmDg0R1YfRBayISyY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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