SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bfc7da6e6e3fd4cdfa329a35305ef662451a5ef8188a22c87b7079a3b455e17d' 
  AND token = 'AUN98wVnX02qhNnWvMasr+EvTOB4jmWA7GOc7vpAR7U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00058

JSON explain

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