SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8ce543c60843e0a525ce54673590876056b4485159540a39f36a31884b73a4cb' 
  AND token = 'HceFTuXbmXY6C8Ux88NQ4YtcVPnv+W0o6KNrGDyB824=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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