Cyrtandra longifructosa 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 : 92-95

Cyrtandra longifructosa M.A.Johnson sp. nov. Figs 7 , 8

Diagnosis.

This species is closely related to C. dolichocarpa (Fig. 8 ), but differs in its glabrous elliptic-ovate leaves (vs. moderately pubescent lanceolate-ovate leaves), blades up to 22 × 9 cm (vs. blades up to 17 × 7 cm), petioles 3-9 cm long (vs. petioles 1-4 cm long), deciduous lanceolate bracts (vs. persistent ovate bracts), peduncles 2-4 mm long (vs. 5-10 mm long), pedicels 11-18 mm long (vs. 21-27 mm long), deciduous beaked calyx (vs. persistent cylindrical calyx), and corolla tube 23-29 mm long (vs. corolla tube 36-55 mm long).

Type.

FIJI. Vanua Levu : ca. 0.8 km NE of Waisali Village along the Waisali Creek, 16°38.51'S, 179°14.54'E, 110 m elev., 09 July 2014, M.A. Johnson 65 with G.J. Hora (holotype: SUVA; isotype: RSA).

Description.

Shrub 0.9-1.7 m tall; stems unbranched to few branched. Leaves opposite, internodes 1-5 cm long, the blades narrowly elliptic to elliptic-ovate, 17-22 cm long, 7-9 cm wide, upper and lower surface glabrous, 8-10 secondary veins on each side, these slightly impressed, margins serrulate, apex acuminate, base oblique to aequilateral and attenuate to cuneate, petioles 3-9 cm long, glabrous to glabrate; inflorescence an axillary cyme, 1- 2(3-4) flowers, densely pilose with black trichomes ca. 1 mm long throughout, peduncle 2-4 mm long, terminated by green bracts, 3-8 mm long, lanceolate, deciduous after anthesis, pedicels 11-18 mm long; calyx pale green, outer and inner surfaces pubescent with appressed uniseriate trichomes, narrowly fusiform in bud, 28-32 mm long, beaked, the 5 lobes often remaining connivent, splitting along one suture 14-19 mm long, deciduous; corolla white, becoming strongly bilabiate in the ovulate phase, tube cylindrical, curved near the mid point, outer surface glabrous, inner surface with uniseriate trichomes throughout and short glandular trichomes near the mouth of the tube, the tube 23-29 mm long, 5-7 mm wide, upper lobes 8-12 mm long and 8-11 mm wide, lower lobe 12-14 mm long and 11-14 mm wide; stamens 2, ca. 6 mm long, base of the filaments reddish orange, anthers apically connate, staminodes 3; nectary disc cupulate, annular, deciduous from mature fruit; gynoecium (ovary, style, and stigma) ca. 24 mm long, ovary glabrous, style pubescent with capitate glandular trichomes along distal ⅓ of its length, stigma bilobed; berries cylindrical, elongate, mature fruit to 40 mm long and 5 mm wide, glabrous, turning white at maturity.

Distribution and ecology.

Cyrtandra longifructosa is known only from one population in the Waisali region of central Vanua Levu, Fiji, where it occurs in the wet forest understory along a small creek at ca. 110 m elevation (Fig. 9 ).

Phenology.

Individuals of this species had flowers, immature fruits, and mature fruits when collected in July.

Etymology.

Named for the elongate cylindrical fruits, one of the diagnostic characteristics of this species.

Phylogenetic placement.

The phylogenetic study by Johnson et al. (2017) placed Cyrtandra longifructosa as sister to C. dolichocarpa (endemic to Vanua Levu and Rabi, Fiji) with strong support (Fig. 4 ). These species both have large bilabiate corollas and elongate cylindrical berries. The key provided in the taxonomic treatment by Gillett (1967) would place C. longifructosa in species Group 3 based on the branching cyme inflorescence, non-woody inflorescence axis, deciduous calyx, inserted anthers and styles, and calyx lobes about the same length as the calyx tube.

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 only at 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. longifructosa . 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 : NE of Waisali Village along Waisali Creek, 16°38.51'S, 179°14.54'E, 110 m elev., 09 July 2014, M.A. Johnson 59 with G.J. Hora ( RSA).

Notes.

The population of C. longifructosa was observed to contain ca. 20 individuals, many of which were reproductive. No other Cyrtandra species were observed growing in the immediate vicinity, although the closely related species C. dolichocarpa , C. waisaliensis , and C. cephalophora were all collected 2.25 km W of the C. longifructosa population described here.

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 7. Cyrtandra longifructosa M. A. Johnson. A Habit B Corolla, staminate phase, anterior view C Mature elongate cylindrical fruit D Inflorescence and young fruit E Corolla, ovulate phase, anterior view. Drawn from Johnson 65 (SUVA, RSA), Johnson 59 (RSA), and field images.

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.