SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '599f767bd85802f0fa8b351f805066b9ba53919f4b5df40b8b14df4c424efa11' 
  AND token = 'Ioipy0IaezGw9Zm6IZ1ybkt/PgLt/j4F29FDVRDldb8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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