SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '19ffcb37570243c6c35402173ba0fcc0ce54ca85c27db0ede613322bb90cefda' 
  AND token = 'QtX/ag7b6Issh2RiH5158BDzIjkkqNuWtTDcaibKMOM=' 
  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"
    }
  }
}