Nicotiana latzii M.W.Chase, R.W.Jobson & Christenh., 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 : 179-184

Nicotiana latzii M.W.Chase, R.W.Jobson & Christenh. , sp. nov.

( Fig. 15.)

Type: Queensland: 5 km east of Ethabuka Station Homestead , 85 m, 23°51′151″S, 138°30′50″E, 14 Oct. 2005, Latz 21442 (holo: NT A0110082 !) .

Diagnosis

Nicotiana latzii is closely related ( Fig. 1 a ) and in morphology similar to N. latifolia and N. sessilifolia , but it lacks the broadly winged petiole and auriculate leaf base and has a shorter floral tube than do these two species. It is also similar to N. simulans N.T.Burb. in floral features, but has a much shorter petiole or wing.

Erect, herbaceous, annual herbs, forming a minimal 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 but only a few small ones in the upper half. Leaves with narrowly winged petioles to nearly sessile, the wing 1.0– 1.5 cm wide, bullate, blades 8.2–12.8 × 1.5–4.8 cm (including petiole), broadly ovate to lanceolate, the apex blunt to acute in the basal leaves, becoming acuminate in those higher up; upper leaf base gently attenuate, many slightly auriculate basally, margins entire, undulate, often basally bullate, uppermost leaves sessile often with a narrowly auriculate base. Vestiture composed of dense, gland-topped short hairs and longer multicellular, non-glandular hairs on all surfaces, in some cases the longer multicellular hairs on leaf margins with 1–2 branches. 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, slightly flaring to clasping, slightly wider and longer in fruit, extending 0.5 cm beyond and surrounding the capsule; the calyx slightly enlarging at maturity. Flowers white, outwardly to upward facing, upper part of the floral tube 0.2 cm longer than the lower. Corolla tube 2.0– 2.5 cm long (from tip of the calyx), slightly longer on the upper side of the flower, 0.2 cm in diameter, with no throat cup, the limb 1.6–1.8 cm across, the lobes slightly cleft, cleft 0.1 cm deep, sinus 0.7 cm deep, lobes 0.6 cm long; four stamens near throat of the floral tube in two pairs, didynamous, the lower pair 0.1 cm longer than the upper pair, and the fifth ~ 0.7 cm deeper in the tube. Fruit a capsule splitting in four lobes, 0.9–1.1 cm long at maturity.

Distribution

Thus far known only from north-central western Queensland between Ethabuka and Glenormiston Stations.

Habitat and ecology

Occurring in open sites, sometimes on the edges of a wetland.

Phenology

Collected in flower in October.

Etymology

Named for Peter K. Latz , who has extensively studied the flora of the central portion of Australia for more than 40 years, contributing his voluminous collections to the Northern Territory Herbarium ( NT) in Alice Springs and elsewhere. He collected the holotype and another specimen of this species on one of his trips to the Ethabuka Station in the far west of Queensland .

Chromosome number

Unlike the other members of the N. simulans complex, which are all n = 20, N. latzii is n = 18 ( M. W. Chase and F. Nollet, unpubl. data).

Notes

Collections of this species could be confused with N. simulans , N. latifolia or N. sessilifolia . The type specimen was originally identified by Latz as N. megalosiphon subsp. sessilifolia , from which it clearly differs in leaf shape and smaller flower (2.0–2.5 v. 3.8–5.0 cm). In addition to the collections at the Ethabuka Station by Latz, this species has been collected by R. W. Jobson east of the Glenormiston Homestead ~ 100 km north-east of Ethabuka. The holotype is represented in the phylogenetic analysis ( Fig. 1 a ) by a secondary specimen grown from viable seeds removed from Latz 21442 and vouchered as Chase & Christenhusz 18074 ( BRI). The other accession ( Fig. 1 a ) is Chase & Christenhusz 18124 ( NSW; BRI), a secondary voucher grown from seeds associated with Jobson 3235 ( NSW).

Specimens examined

QUEENSLAND. 14 km east of Ethabuka Homestead, Gypsum Hill, 23.8492°S, 138.6128°E, 15 Oct. 2005, Latz 21474 ( NT A0110202 !); anabranch of the Georgina River, Donohue Highway , 24 km east of Glenormiston Homestead , swampy roadside vegetation, 160 m, 22°53′43″S, 139°2′21″E, 30 Sep. 2016, Jobson 3235 ( NSW) .

Figures

Fig. 1. Phylogenetic tree for the species of Nicotiana section Suaveolentes, based on the RADseq (nuclear) data matrix of Chase et al. (2021, 2022b), to which we have added the accessions for the new species reported in this paper. Vouchers for these added accessions are indicated under the additional specimens examined for each of the new species. All nodes for which there are no bootstrap percentages indicated are 100. (a) The basal nodes of the RADseq tree. (b) The more derived clades in the same RADseq tree as in (a).