Nicotiana praecipitis M.W.Chase & K.Durham, 2023

Bruhl, Jeremy J., Andrew, Damien D., Palsson, Ruth, Jobson, Richard W., Taseski, Guy M. & Samuel, Rosabelle, 2023, Nine new species of Australian Nicotiana (Solanaceae), Australian Systematic Botany 36 (3), pp. 167-205 : 188-190

Nicotiana praecipitis M.W.Chase & K.Durham , sp. nov.

( Fig. 19–21 .)

Type: New South Wales. Mount Kaputar NP, Mount Coryah Track , 1353 m, 30°16′50.96″S, 150°7′21.41″E, 29 Mar. 2021, Durham 97 & Palsson (holo: NSW; iso: NE 111470 ) .

Diagnosis

Nicotiana praecipitis is morphologically similar to N. olens and N. suaveolens , but it has differently shaped leaves with prominent hair-tipped teeth; the inflorescence structure is more upright and branched basally, with a larger flower in N. praeciptis (5.4–5.7 v. 1.8–4.2 cm) with the upper tube longer than the lower and slightly didynamous stamens. Nicotiana suaveolens has a mat of thick hairs on the bases of its stems and more stem leaves that rarely bear teeth.

Erect, herbaceous, short-lived perennial herbs, forming a small rosette, but with numerous large leaves in the basal portion of the stems, the main stem with major branches in the lower half of the inflorescence and a few larger ones in the upper half. Leaves with narrowly winged petioles, the wing 0.3–0.5 cm wide, with the base so gradually attenuate that the length of the petiole is arbitrarily determined, blades 9.5–30.5 × 2.8–15.5 cm (including petiole), ovate to lanceolate, the apex blunt to acute in the basal leaves, becoming acuminate in those higher up, margins undulate, with teeth topped by a multicellular, often bent and sometimes branched hair, base gently attenuate and often bullate; upper leaves initially petiolate, becoming narrow and almost sessile above. Vestiture composed of sparse, long, multicellular non-glandular hairs on the basal stems, leaf veins and margins and floral tubes, becoming glabrous on upper stems and leaves, pedicels and calyces with short glandular hairs and broadly based longer hairs with a smaller gland. Inflorescence bracts sessile, linear lanceolate, ~ 0.5–2.3 cm long, the apex acuminate. Calyx 1.4–1.6 × 0.2 cm, one lobe slightly longer and one shorter than the others, the tips acuminate and reflexed, 0.3–0.5 cm longer than and surrounding the fruit, the calyx persistent and enlarged slightly at maturity. Flowers white, out-facing, not pendent, upper part of the floral tube longer than the lower and projecting outward. Corolla tube 5.4–5.7 cm long (from tip of the calyx), 0.3 cm in diameter with a throat cup, upper part of tube slightly longer than the lower, the limb 3.0– 3.8 cm across, the lobes slightly cleft, cleft 0.1 cm deep, sinus 0.8 cm deep, lobe 1.2–1.5 cm long; stamens five, upper two 0.15 cm longer than the lower two, all four attached near throat of the floral tube, the fifth 1.5 cm deeper in the tube, all with the filaments 0.1–0.2 cm long. Fruit a capsule splitting in four lobes, 0.9–1.2 cm long at maturity.

Distribution

Known thus far only from the type collection on the Mount Coryah Walking Track, Kaputar National Park , New South Wales ( Fig. 14 ) .

Habitat and ecology

On high ledges near the cliff top and the base of rock faces with an east-south-eastern aspect, in dark gravelly soil between basalt boulders ( Fig. 21 ) of the Nandewar Volcanic Complex ( Abbott 1969). It grows in an area that occasionally experiences snow in the austral winter.

Phenology

Collected in flower in late March.

Etymology

Named for the rocky ledges below the summit on which it perches, from the Latin for precipitous.

Chromosome number

Unknown.

Notes

This species would most likely be confused with N. suaveolens Lehm. , but no previous collections of the new species have been located. It was discovered by Kay Durham and Ruth Palsson while hiking the Mount Coryah Walking Trail, not looking specifically for Nicotiana . Ruth had walked past when Kay noticed it, remarking to Ruth, ‘Isn’t that a Nicotiana ?’

Its habit and habitat are unusual for the genus. There are no records of Nicotiana collected in Mount Kaputar National Park on AVH or Bionet apart from Constable s.n. ( NSW 48734!), which is N. forsteri . However, this specimen was mistakenly attributed to Mount Lindsay in Mount Kaputar National Park. The location details are in the process of being corrected ( R. Palssen, pers. comm.). On the same day, 25 May 1949, Constable appears to have collected ~ 40 specimens at Mount Lindesay, north-west of Kyogle, New South Wales, and various other mountains with the same or similar name in eastern Australia. In each case, he misspelt Lindesay as Lindsay, which is the name of the mountain in Mount Kaputar National Park but unlikely to have been visited on the same day as Mount Lindesay. Palsson and Durham have sighted Nicotiana forsteri at several locations in Mount Kaputar National Park at much lower elevations, ~ 500 m, but did not have a permit to collect on those instances. The material illustrated here ( Fig. 19 , 20) and used in the RADseq analysis was grown from seeds of the original gathering and has been given a secondary number, Chase & Christenhusz 21008 ( CANB, K).

Figures

Fig. 19. Nicotiana praecipitis, based on living plants cultivated at the Royal Botanic Gardens, Kew, grown from seeds associated with the holotype Durham 97 & Palsson (NSW). Painted by Deborah Lambkin.

Fig. 14. Map of the distributions of Nicotiana megalosiphon (green circles), N. latifolia (red circles), N. sessilifolia (blue circles), N. gibbosa (rose-purple circles), N. praecipitis (orange circle) and N. bungonia (aqua circle). Created by Maarten Christenhusz from data downloaded from the Australasian Virtual Herbarium website.

Fig. 21. (a) Habitat of Nicotiana praecipitis on the Mount Coryah Walking Track, Mount Kaputar National Park, New South Wales. Photograph by Ruth Palsson. (b) Habit of Nicotiana praecipitis, Mount Coryah Walking Track, Mount Kaputar National Park, New South Wales. Photograph by Kay Durham.