SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b5fe85ab9e4dd650438aac657314ed40808023aa9f6fd816a995e4f9b1e2df19' 
  AND token = 'Q+XYPu/5OjY5IVv+ol0W6y/XClRDEJIs/2NJ7uNavcQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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