Cyrtandra waisaliensis M.A.Johnson, 2017

Johnson, Melissa A., 2017, Four new species of Cyrtandra (Gesneriaceae) from the South Pacific islands of Fiji, PhytoKeys 91, pp. 85-104 : 95-99

Cyrtandra waisaliensis M.A.Johnson sp. nov. Figs 10 , 11

Diagnosis.

The new species is closely related to C. dolichocarpa and C. longifructosa (Fig. 8 ), but differs in its dense bristly pubescence on the young stems, leaves, petioles, and inflorescences (vs. moderate appressed pubescence on C. dolichocarpa ; vs. glabrous on C. longifructosa ), cauliflorous inflorescences (vs. axillary inflorescences in both C. dolichocarpa and C. longifructosa ), persistent foliaceous ovate white bracts to 10 mm long (vs. non-foliaceous green bracts to 5 mm long in C. dolichocarpa ; vs. deciduous non-foliaceous lanceolate green bracts to 8 mm long in C. longifructosa ), and multiple persistent foliaceous white bracteoles (vs. single deciduous non-foliaceous green bracteoles in C. dolichocarpa ; vs. bracteoles absent in C. longifructosa ).

Type.

FIJI. Vanua Levu : Waisali Forest Reserve along the lower portion of the Savuqoro Creek, 16°38.39'S, 179°13.25'E, 338 m elev., 07 July 2014, M.A. Johnson 50 with G.J. Hora (holotype: SUVA; isotype: RSA).

Description.

Shrub 0.7-2.6 m tall; stems few- to many-branched, young stems covered in hirsute trichomes. Leaves opposite, those at a node unequal, internodes 2-8 cm long, blades ovate to obovate, 13-24 cm long, 6-12 cm wide, upper and lower surfaces densely hirsute with uniseriate multicellular trichomes, 6-7 secondary veins on each side, margins serrate, apex acuminate, base oblique to aequilateral and attenuate to cuneate, petioles 3-11 cm long, densely hirsute, trichomes ca. 5 mm long; inflorescence of cauliflorous cymes, 2-8 flowered, cymules 1-4 flowered, densely hirsute throughout, peduncle 3-8 mm long, terminated by persistent foliaceous white bracts, ovate to lanceolate, 3-10 mm long, outer surface glabrous to glabrate, inner surface densely hirsute, pedicels 21 -40 mm long, subtended by multiple persistent bracteoles similar to and closely subtended by the outer bracts; calyx white, cylindrical, densely hirsute, 23-37 mm long, unequally cleft into 5 triangular lobes, 4-14 mm long, persistent; corolla white, bilabiate, tube funnelform, curved near mid point, outer surface glabrous to glabrate, inner surface with capitate glandular trichomes near the mouth of the tube, 23-27 mm long, 6-9 mm wide, upper lobes 11-12 mm long and 8-11 mm wide, lower lobe 13-17 mm long and 10-15 mm wide; stamens 2, 3-6 mm long, base of the filaments reddish orange, anthers apically connate, staminodes 3; nectary disc prominent, annular, 2 mm high; gynoecium (ovary, style, and stigma) 16-26 mm long, ovary glabrous, style pubescent with capitate glandular trichomes along distal ⅓ of length, stigma bilobed; berries ellipsoid, green when immature, enclosed by the persistent calyx, mature fruit not seen.

Distribution and ecology.

Cyrtandra waisaliensis is known only from one population in the Waisali Forest Reserve on Vanua Levu, Fiji at 300-360 m elevation, occurring in the dense forest understory alongside a creek (Fig. 9 ).

Phenology.

Flowers and immature fruits were observed in July, with fruits likely becoming mature ca. 5-6 months later (December-January).

Etymology.

The new species is named after the area of Vanua Levu where it was collected, Waisali Forest Reserve.

Phylogenetic placement.

A recent phylogenetic study by Johnson et al. (2017) supported the placement of Cyrtandra waisaliensis as sister to C. longifructosa (endemic to Vanua Levu) and C. dolichocarpa (endemic to Vanua Levu and Rabi; Fig. 4 ). These species all have large bilabiate corollas, and both C. dolichocarpa and C. longifructosa have elongate cylindrical white fruits. However, C. waisaliensis is also morphologically similar to C. hispida ; these species share bilabiate corollas, persistent cylindrical caly ces, and a dense indument of stiff uniseriate trichomes. Cyrtandra hispida is currently placed in a polytomy with C. cephalophora and the clade comprising C. waisaliensis , C. longifructosa , and C. dolichocarpa . The key provided in the taxonomic treatment by Gillett (1967) would place C. waisaliensis in species Group 2, based on the branching cyme inflorescence and the persistent calyx.

Conservation status.

Proposed IUCN Red List Category: Critically Endangered (CR) based on an estimated area of occupancy of <10 km2 (criterion B2), known to exist at only a single location (B2a), projected decline in extent of occurrence (B2bi), area of occupancy (B2bii), and area, extent, and/or quality of habitat (B2biii). This species is only known from one locality in the central mountains of Vanua Levu, warranting additional surveys in areas of Vanua Levu with intact rainforest (e.g., Waisali, the Natewa Peninsula) to determine the full extent of occurrence and population demographics of C. waisaliensis . Regions with suitable rainforest habitat on Vanua Levu are threatened by logging, mining for bauxite and gold, invasive plant species such as Clidemia hirta ( Koster’s curse; M. Johnson, pers. obs.), and tropical cyclones.

Additional specimens examined.

FIJI. Vanua Levu : Waisali Forest Reserve along the lower portion of the Savuqoro Creek, 16°38.34'S, 179°13.18'E, 355 m elev., 07 July 2014, M.A. Johnson 48 with G.J. Hora ( RSA).

Notes.

The observed population of C. waisaliensis was comprised of ca. 20 individuals, many of which were reproductive. A single individual appeared to be of hybrid origin, with the putative parents being C. waisaliensis and C. cephalophora based on morphological characters intermediate between these two species.

Figures

Figure 4. A portion of the Maximum Likelihood phylogram from Johnson et al. (2017) based on three nuclear (ITS, ETS, Cyrt 1) and two chloroplast (psb A- trn H, rpl 32 - trn L) loci. Support values shown for each branch are bootstrap and posterior probabilities when ≥ 50 % and ≥ 0.50, respectively. An asterisk indicates 100 % BS or 1.0 PP; a dash indicates that the branch was not supported.

Figure 8. Cyrtandra longifructosa M. A. Johnson and closest relative (C. dolichocarpa) based on molecular phylogeny by Johnson et al. (2017). A C. longifructosa corolla, anterior view B C. longifructosa flower, lateral view C C. longifructosa elongate cylindrical fruits D C. longifructosa axillary inflorescence and young fruits E C. longifructosa shrub habit F C. dolichocarpa corolla, anterior view G C. dolichocarpa flower, lateral view H C. dolichocarpa shrub habit. All photos taken in the field by M. Johnson, with photos of C. longifructosa taken from the type collection.

Figure 9. Distribution of Cyrtandra waisaliensis and C. longifructosa on Vanua Levu, Fiji.

Figure 10. Cyrtandra waisaliensis M. A. Johnson. A Habit B Cauliflorous inflorescence C Corolla, anterior view D Corolla, longitudinal section E Gynoecium F Calyx, longitudinal section and young fruit. Drawn from Johnson 48 (RSA), Johnson 50 (SUVA, RSA), and field images.

Figure 11. Cyrtandra waisaliensis M. A. Johnson. A Corolla, anterior view B Flower, lateral view C Cauliflorous cyme inflorescence D Shrub habit E Rainforest understory habitat. All photos from the type collection, taken in the field by M. Johnson.