SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9daa2d0da18759b0723f1043b62855886c5633f3dc037cdc3eb1bc39ac8f2bf0' 
  AND token = 'pors2nAAtpKghoKpnfLJcCeRkTS/jDEtc+eIapfkQiM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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