''Cryptocarya mackinnoniana'' is a species of tree in the

Lauraceae Lauraceae, or the laurels, is a plant family that includes the true laurel and its closest relatives. This family comprises about 2850 known species in about 45 genera worldwide (Christenhusz & Byng 2016 ). They are dicotyledons, and occur ma ...

family. Growing up to 25m in size, it is found in well developed rainforests from the

Iron Range The term Iron Range refers collectively or individually to a number of elongated iron-ore mining districts around Lake Superior in the United States and Canada. Much of the ore-bearing region lies alongside the range of granite hills formed by ...

area on

Cape York Peninsula Cape York Peninsula is a large peninsula located in Far North Queensland, Australia. It is the largest unspoiled wilderness in northern Australia.Mittermeier, R.E. et al. (2002). Wilderness: Earth’s last wild places. Mexico City: Agrupación ...

south to Paluma in

North Queensland North Queensland or the Northern Region is the northern part of the Australian state of Queensland that lies just south of Far North Queensland. Queensland is a massive state, larger than many countries, and its tropical northern part has been ...

Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...

. It was first botanically described by

Ferdinand von Mueller Baron Sir Ferdinand Jacob Heinrich von Mueller, (german: Müller; 30 June 1825 – 10 October 1896) was a German-Australian physician, geographer, and most notably, a botanist. He was appointed government botanist for the then colony of Vict ...

in Fragmenta Phytographiae Australiae 5: 169 (1865).

Description

The stem has a thin creamy to pale brownish coloured layer which can usually be seen under the subrhytidome layer just outside of the stem's outer blaze. The twigs feature fluted grooves with a dense mixture of different hairs, the longer ones are tortuous whilst the shorter hairs have a more papillate form. The hairs range in colour from dark brown through to pale brown and usually sit erect and can remain on twigs which are quite old. Lenticels are also normally visible on the older twigs with a round and elongated appearance. The leaf blades have dimensions ranging from approximately 13-35 x 4.5-8.5 centimetres and have a slight glaucous layer underneath along with hairs which are tortuous, brown in colour and erect . On their upper surface the leaves have a depressed midrib and petioles which can be ridged, flat or channelled. On the underside of the leaf blade reticulate veins are raised in a pronounced manner which forms a well defined network. The form of the flowers is paniculate and located beyond the leaves whilst their perfume has been often described as unpleasant. The perianth tube's inner surface is pubescent whilst the tepals are approximately 1.1-1.9 mm long and feature an outer surface which is also pubescent. The ovary usually has no hairs but is occasionally pubescent whilst the style is glabrous. The fruits feature spots with small pustules that usually have a form which is ellipsoid but can occasionally be more ovoid or obpyriform. The fruits are 19-28 x 13-17 mm in size with cotyledons that range from creamy to yellowish.

Seedlings

Seeds will germinate from 20 to 103 days. The first pair of leaves are elliptic to ovate, about long and wide and are glaucous on the underside. By the time they have reached the tenth leaf stage Cryptocarya mackinnoniana seedlings will have developed a slightly glaucous layer on the underside of their leaf blades. Young leaves feature hairs upon the top and underside whilst older leaves keep some very short hairs predominantly along the midrib on the upper surface. Oil dots are just visible under magnification.

Distribution and ecology

Cryptocarya mackinnoniana occurs in rain forest at

and North Eastern Queensland from

sea level Mean sea level (MSL, often shortened to sea level) is an average surface level of one or more among Earth's coastal bodies of water from which heights such as elevation may be measured. The global MSL is a type of vertical datuma standardised g ...

to an altitude of . Flowering usually occurs between October–May and the fruit are eaten by many bird species and native rats.

Common names

Rusty Laurel, Rusty leaved Laurel, Mackinnon's walnut, Mackinnon's laurel and Rusty-leaved walnut.

References

{{taxonbar, from=Q15607702 mackinnoniana Flora of Queensland Taxa named by Ferdinand von Mueller Plants described in 1865