Diuris daltonii
# Diuris daltonii

Diuris daltonii is a species of orchid that is endemic to western Victoria. It has one or two leaves and up to seven purple flowers and is similar to D. punctata, with which it was previously included..

## Description

Diuris daltonii is a tuberous, perennial herb usually with up one or two, sometimes up to four linear, channelled leaves, 150–250 mm (5.9–9.8 in) long. Up to seven dark purple flowers are borne on a flowering stem 20–50 mm (0.79–1.97 in) tall. The dorsal is erect and broadly egg-shaped, 12–17 mm (0.47–0.67 in) long, the lateral sepals narrowly linear, 30–60 mm (1.2–2.4 in) long and usually parallel. The petals are erect, egg-shaped to elliptic and 12–25 mm (0.47–0.98 in) long. The labellum is 10–16 mm (0.39–0.63 in) long and has three lobes, the centre broadly fan-shaped and keeled, with a longer stalk than in the related D. punctata, and the side lobes erect and less than half as long as the middle lobe. There are two yellow calli ridges near the mid-line of the labellum. Flowering occurs from October to December.

## Taxonomy and naming

This donkey orchid was first formally described in 1906 by Carl Walter who gave it the name Diuris punctata var. daltonii in The Victorian Naturalist from specimens collected by St. Eloy D'Alton on Mount Arapiles in 1906. In 2004, David Jones and Mark Clements raised the variety to species status as D. daltonii in The Orchadian. The specific epithet (daltonii) honours the collector of the type specimens.

## Distribution and habitat

This orchid grows in heathy forest and in River Red Gum woodland between Mount Arapiles and the Grampians in western Victoria.

## Conservation status

Diuris daltonii is listed as "critically endangered" under the Victorian Government Flora and Fauna Guarantee Act 1988.

