SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9add1c824bc117d2f58ef032ca977c549814d24cb628e6e84907d6fccda4c6ee' 
  AND token = 'XGQRNZ4JHGqNoBvkl5PZP+bN8H4xNwHZitFUnIcFHag=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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