SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '83bf84051d69d39dba0869f147a67f69483bb52269f85454c0ee0a12b76830f2' 
  AND token = 'ZT24GzajGzOgR+1yP7UbKHtJY79xr4TauZ6anK9zqXs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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