SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd706602399dbf0efbdf6b7d48653b69363b9d8bf403d1189475c969aa6706472' 
  AND token = 'Zbs8aC18jlaTgER3prdRv84ktz+gkFhFuuV2dBGcFq4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}