SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '444e8a344f388e6e7664dd5af7451e377c8d55ce3eb3e63e732783107b00668d' 
  AND token = 'o97LZu7L2k582mQdOVRhZRmLnvFrD79ONCHmTlx1RAg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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