Parahebe jovellanoides (Garn.-Jones & de Lange) de Lange
Veronica jovellanoides, commonly known as Riverhead speedwell, is a threatened flowering plant in the family Plantaginaceae. It is endemic to New Zealand, where only three plants are known in the wild. All are found within the Ernest Morgan Reserve, a 20ha forest northwest of Auckland. Its discovery is accredited to a retired plant nursery owner, Geoff Davidson, who organised the land's protection a few decades prior, and found it by chance on a walk in November 2007.[3]
V. jovellanoides has a
pollinated, these become small brown seeds which are dispersed
by the wind.
Description
Veronica jovellanoides is a creeping plant which grows into a mat 2 to 3 m (6.6 to 9.8 ft) across. It has 2 m (6.6 ft) long red-brown
nodes spaced 5 to 30 mm (0.20 to 1.2 in) apart. Although it can cover a large area, it grows prostrate and only reaches a height of 5 centimetres (2.0 in). It has 3.5 to 11 mm (0.14 to 0.43 in) by 4.5 to 12 mm (0.18 to 0.47 in) spatula-shaped leaves which are green on top and a paler green below. The leaves may also grow on top of one another, have reddish margins, and are suspended from 2 to 10 mm long very hairy petioles. In addition to this, the leaves are hairy and toothed; with three to five pairs of teeth on each side.[1][2][5]
Flowering occurs from October to December and produces a white
corolla (four petals) and a purple ring around its throat; the ring serving as a nectar guide for pollinators. The flower is 10 to 12 mm (0.39 to 0.47 in) in diameter and the throat is a yellow-green colour. Each inflorescence is made up of up to seven flowers growing off of a raceme-like structure made of a 15-to-25 mm (0.59-to-0.98 in) long peduncle and a 20 to 30 mm (0.79 to 1.2 in) rachis. Pollen is given out by a stamen made of a 4.0-to-4.5 mm (0.16-to-0.18 in) long filament and a 0.8 to 1.0 mm long pink anther, the pollination of which is encouraged by a glabrous nectarial disk.[2][5]
Fruiting is from December to February, yielding pale brown 1.2 to 1.8 mm by 1 to 1.4 mm seeds. The 3.2 to 6.0 mm (0.13 to 0.24 in) by 3.5 to 5.5 mm (0.14 to 0.22 in) pale brown capsules split open on wetting, revealing the similarly-coloured and deeply flattened seed. There are six to ten seeds per locule, within the 0.6 to 0.8 mm long glabrous ovary. V. jovellanoides has 20 pairs of chromosomes.[2][5]
Leaves
A close up of the flower.
Seeds
Taxonomy
Discovery and naming
New Zealand Journal of Botany (NZJB) in 2009.[5][7] In 2010 Peter de Lange moved the species into the genusParahebe because many botanists believed that it should be separate from Veronica, though more recent scientific consensus among botanists is that Parahebe, along with many similar genera, should be merged with Veronica.[2]
V. jovellanoides does not resemble other species in the genus Veronica, being highly distinctive. Species from the
morphologically similar. V. spathulata, for example, shares its lack of folds and also has spatula-shaped leaves, but has different flowers and is otherwise dissimilar. These features, or lack thereof, they argued, suggest that it diverged early from the Parahebe clade, an idea supported by a then unpublished genetic analysis.[5] This analysis was published in the NZJB in 2013 and in it they concluded that V. jovellanoides' 20 pairs of chromosomes was unusual given the very few related species that shared the number.[8]
Etymology
The
specific epithet jovellanoides is due to its similarity to Jovellana repens with which it was first confused.[5][7] The common name Riverhead speedwell is after the Riverhead Pine Plantation, a popular recreation spot for Aucklanders, located close to the Ernest Morgan Reserve.[9][10]
V. jovellanoides was given the nickname "Bamboozle", meaning to confuse or throw off,[11] by botanists due to its elusive nature. On trying to find the plant again after its discovery, four people searched the reserve for 80 hours without locating it. Only when 40 members of the Auckland Botanical Society walked together in a line did they find one patch of it.[7]
There are only three plants known in the wild, all within an area of 6 m2 (7.2 sq yd) just 35 m (38 yd) above sea level, growing on a shaded and damp clay bank among ferns, mosses and
The three known wild specimens grow in association with Uncinia banksii,
Freycinetia banksii. A large number of lichens and bryophytes were also found in the area including: Achrophyllum dentatum, Balantiopsis diplophylla, Bazzania adnexa, Heteroscyphus cunestipulis, Lembidium nutans, Leiomitria lanata, Monoclea forsteri, Paracromastigium furcifolium, Pendulothecium auriculatum, Pyrrhobryum bifarium, Pseudocyphellaria dissimilis, P. multifida, Trichocolea mollisima, and Sticta lacera.[5]
Cultivation
V. jovellanoides is easily grown from both rooted pieces and stem cuttings, but growing from seed has not been tested as of 2009. Plants grown in Wellington have been observed to be very susceptible to a powdery mildew, though at Davidson's nursery in Auckland, where other nearby plants were being affected by a mildew, V. jovellanoides was not. In late summer (February in New Zealand) and autumn (March to May) it has been recorded dying back and becoming more difficult to maintain generally.[5] It grows best in a sunny spot with only a small amount of shade and through some scoria pebbles or a similarly gritty material.[13]
^Lamb, Harriet (September 2001). "Riverhead: An urban forest". New Zealand Geographic. Archived from the original on 20 January 2021. Retrieved 19 February 2021.
Leaves
A close up of the flower.
Seeds
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