Villaria lanceolata (Merrill) Alejandro & Meve, 2016

Alejandro, Grecebio Jonathan D. & Meve, Ulrich, 2016, Recollection of former Randia species, recognition of a rheophytic species of the Philippine endemic Villaria (Octotropideae, Rubiaceae), Phytotaxa 253 (2), pp. 171-175 : 173-175

Villaria lanceolata (Merrill) Alejandro & Meve , comb. nov. ( Figs. 1 , 3 )

≡ Randia lanceolata Merrill., Philipp. J. Sci. , 8: 57. 1913. Type:— PHILIPPINES. Cagayan:Abulug River, near Tauit, 18 o 23’N, 121 o 26’E, February 1912, Fischer 11626. (holotype PNH, destroyed. Neotype (here designated), PHILIPPINES: Apayao, May 1917, E. Fenix 28123, US!)

= Randia stenophylla Merrill, Philipp. J. Sci. , 5: 245. 1910, nom. illeg, [ICN, Art. 53.1]. Type:— PHILIPPINES. Bulacan: Norzagaray , 14 o 54’N ; 121 o 10’E, 16 June 1907, Curran Bureau of Sci. No. 7170 (holotype PNH, destroyed; lectotype, designated here, US!)

Rheophytic shrub or small tree, 2 – 3 m high; branches terete, glabrous to puberulent. Stipules lanceolate to ovate, 3 – 7(– 9) mm long, apex acuminate, rarely keeled, abaxially puberulent along the base continuing through the middle, adaxially basally puberulent. Leaf blades narrowly lanceolate, 3.5 – 11 × 0.5 – 1.5 cm, (sub)coriaceous, glabrous on both sides or except the puberulent midrib and lateral nerves, adaxially shining, abaxially dull green, base acute, apex acuminate, midrib prominent, lateral nerves 10 – 13 pairs which are inconspicuous on both sides; petioles 1 – 3 mm long, puberulent. Inflorescences (supra)axillary, usually less than 1 mm above the nodes, solitary or cyme; peduncle 1.2 – 3.5(– 4.5) cm long, puberulent; bracts lanceolate to triangular, 1 – 3 mm × 1 mm, usually paired subtending the flowers, puberulent. Flowers (4–)5-merous; pedicels 2 – 3 mm long, puberulent. Calyx tube 2 – 4 mm long, puberulent outside; lobes ovate-oblong, 2.5 – 5 × 2.5 – 4 mm, apex acuminate to rounded, somewhat fused at the base. Corolla tube infundibular, 3 – 5 mm long, densely pilose at the throat inside, puberulent outside; lobes white, elliptic to ovate, apex rounded or acute, 3.5 – 6 × 3 – 5.5 mm long, recurved. Stamens inserted; filaments short, adnate to the corolla tube; anthers linear, 2.5 – 3 mm long, glabrous, epipetalous, dorsimedifixed, white, turning brown at anthesis; Style terete, 2 – 3 mm long, glabrous, bilobed; style branches elliptic, 3 – 4 mm long, white, densely pilose, partially exserted. Ovary unilocular, biparietal placenta, form partially completed septa with a slit about 2 – 3 mm near the apex; ovules 12 – 16, horizontally attached to the septa. Fruits ellipsoid to globose, 8 – 10 × 6 – 10 mm, green, turning red when ripe, glabrous or puberulent, fleshy, berry-like, calyces persistent; peduncle 3 – 5 mm long, glabrous or puberulent. Seeds numerous, angular-ovoid, ± flattened, 2 – 4 mm long, greenish white on young fruits, turning brown in mature fruits; exotesta fibrous, with prominent parallel ridges.

Local Names:— Marasibat, salik-salik (Isneg).

Phenology:— Villaria lanceolata has been observed to be flowering and fruiting from November to February, and April to June.

Distribution and Habitat:— Villaria lanceolata has been found in Luzon, restricted to the provinces of Apayao, Bulacan and Cagayan. Its habit (tough and flexible stems, lanceolate and glossy willow-like leaves) and the streambed habitat characterize this species as a rheophyte sensu Van Steenis (1952). Villaria lanceolata has been typically collected on sandy substrate to stony cliffs along riverbanks and streams subject to overflow during rainy seasons. Species were found also to thrive as well on plant litter and soil deposits on other trees and plants but never epiphytic. Its known altitudinal extent is 30 – 130 m asl.

Discussion:—The specific epithet “ stenophylla ”, supposedly having priority over “ lanceolata ”, cannot be used because of the earlier homonym Randia stenophylla K. Krause (1909: 140 ; nowadays regarded as synonym of Rothmannia urcelliformis (Schweinf. ex Hiern) Bullock ex Robyns ); thus, making R. stenophylla Merr. illegitimate. The cited type specimens of Randia lanceolata ( Merrill 1913: 57) and R. stenophylla ( Merrill 1910: 245–246) were apparently destroyed in PNH during the World War II. There were no isotypes distributed for R. lanceolata ; thus, E. Fenix 28123 collection of a fruiting branch found in US herbarium is designated as the neotype. For R. stenophylla , the only isotype located is available at US, and is here designated as the lectotype.

Villaria lanceolata is rather unique from the rest of the Villaria species by its rheophytic habit, narrowly lanceolate leaves, bright red fruits when ripe and the presence of parallel ridges in the fibrous testa of seeds. The locals in the province of Apayao named the plant “ salik-salik” in reference to salicylic acid. Traditionally, they crushed the leaves of V. lanceolata and applied to body parts with fungal infections.

Additional Specimens Examined:— PHILIPPINES: Apayao, Pudtol, Nagan River , 16 November 2009, B. O. C. Lemana 25080 ( L, K, US, PNH, USTH), 25081 ( L, K, US, PNH, USTH), 25082 ( L, US, USTH), 25083 ( K, USTH) ; Apayao, Pudtol, Nagan River , 29 January 2010, B. O. C Lemana 25084 ( L, PNH, USTH) ; Bulacan, Norzagaray, Angat Dam , May 2010, A. Fernandez et al. 25092 ( PNH, USTH <2 sheets>), July 2010, J. Osorio et al. 25093 ( PNH, USTH <3sheets>) .

IUCN Red List category (2012):— Endangered [EN; C2ai], population size is estimated to number fewer than 2,500 mature individuals. A continuing decline is projected and no subpopulation is estimated to contain more than 250 mature individuals or even more than 100. Some areas occupied by V. lanceolata are fragmented forests caused by logging activities; others are threatened by human land use such as in Bulacan, Norzagaray and Apayao, Pudtol. The populations in riverbanks may be possibly swipe off during the rainy seasons or several typhoons in a year.

Figures

FIGURE 1. Villaria lanceolata—A. habit; B. open anthesal flower; C. flowering branch showing paired axillary flowers; D. immature fruits; E. mature fruit; F. longitudinal section of fruit showing numerous seeds (A,C,D,F from Lemana 25080, USTH; B&E from Osorio et al. 25093, USTH).

FIGURE 3. Villaria lanceolata—A. flowering branch; B. portion of stem with stipule; C. corolla bud with contorted aestivation; D. top view of open anthesal flower; E. open anthesal flower showing partially exserted stigma; F. longitudinal section through ovary; G. fruit; H. longitudinal section of fruit; I. cross section of fruit (A–F from Lemana 25080, USTH; G–I from Osorio et al. 25093, USTH).