SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8728bb6af2c43e89403f8e1d63a559e04c8c01450a46df21ff96f3e0b5e7e82c' 
  AND token = 'G9mKnVFoik09THClQokIuBronhFLTR47AEXvcFa/3O0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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