Suaeda novae-zelandiae aka Sea Blite

Suaeda novae-zelandiae, commonly known as sea blite or New Zealand seablite, is a small, salt-tolerant subshrub endemic to the coasts of New Zealand. It belongs to the goosefoot alliance within the family Amaranthaceae (traditionally placed in Chenopodiaceae), and was formally described by botanist Harry Howard Allan in the landmark first volume of the Flora of New Zealand in 1961. The specific epithet novae-zelandiae simply means 'of New Zealand', a nod to its restricted distribution, while the genus name Suaeda derives from an Arabic vernacular name recorded by the 18th-century naturalist Peter Forsskål along the Red Sea.

In habit the plant is a perennial, much-branched subshrub that rarely rises far above the tide line. Woody, somewhat sprawling stems bear persistent leaf-bases and, in older specimens, reach thirty centimetres or more in length, with branchlets becoming noticeably grooved as they dry. The foliage is highly succulent, a classic adaptation to saline, physiologically dry conditions. Leaves are sessile and variable in arrangement, appearing opposite, alternate, or in small clusters on the same individual. Each leaf is fleshy, linear to narrow-oblong (occasionally narrow-obovate), faintly apiculate, and measures only about four to twelve millimetres long by one to two millimetres wide. The tiny axillary flowers are borne singly or in groups of three to four, each subtended by two bracteoles. They have a modest five-lobed perianth with erect, ovate lobes and two or three stigmas, reflecting the wind-pollinated habit typical of the subfamily Suaedoideae. Seeds are horizontal, red-brown and glossy, and the plant flowers and fruits over the warmer months, from November through March.

Suaeda novae-zelandiae is a true halophyte of coastal saltmarsh and estuarine margins. It grows on both the North and South Islands of New Zealand, with records spanning North Auckland, South Auckland, Nelson, Canterbury and Otago land districts. Typical habitats include the upper reaches of intertidal saltmarsh, sandy or silty tidal flats, the landward edges of mangrove stands, and brackish lagoon shores where regular tidal inundation alternates with periods of drying. The New Zealand Plant Conservation Network classifies it as a facultative wetland species, meaning it tolerates but does not strictly require waterlogged soils; its succulent tissues let it manage the osmotic stress of saline substrates and its woody base helps it endure wind, spray and occasional scouring by storm tides.

Ecologically, sea blite is a modest but important component of New Zealand's native saltmarsh flora, often growing alongside species such as glasswort (Salicornia quinqueflora), Selliera radicans, Samolus repens and remuremu. These low halophytic communities stabilise fine coastal sediments, provide cover for invertebrates and nursery habitat for estuarine fauna, and act as a buffer between the open sea and terrestrial ecosystems. Although sea blite is currently listed as Not Threatened under the New Zealand Threat Classification System, it has been assessed as Regionally At Risk – Declining in Auckland, reflecting ongoing pressures on estuarine habitats from land reclamation, pollution, grazing, vehicle traffic on tidal flats and the spread of invasive cordgrass (Spartina). It is not commercially cultivated and is seldom seen outside its natural coastal habitat, but where saltmarsh remains intact it can form persistent, sprawling colonies that offer a quietly distinctive presence on New Zealand's shores.