Timonius bullatus K.M.Wong & J.Chen, 2014

Chen, Junhao, Wong, Khoon Meng, Ent, Antony Van Der & Tan, Hugh T. W., 2014, Nine new species of Timonius (Rubiaceae) from Kinabalu Park, Borneo, Phytotaxa 181 (3), pp. 138-150 : 143

Timonius bullatus K.M.Wong & J.Chen , sp. nov. ( Figs. 2E & 2G )

Similar to Timonius polyneurus Valeton (1909: 59) ( Fig. 2F ), but differing by fewer secondary veins (8–12 vs. 12–17) and the slightly to conspicuously bullate (vs. plane) upper lamina.

Type: — BORNEO. Sabah: Kinabalu Park , eastern shoulder, 6° 5′ N, 116° 36–40′ E, 2440 m, 10 July 1961 (♀ plant), Chew et al. RSNB 184 (holotype SING; isotypes BO, K, L, SAN) .

Timonius borneensis sensu Beaman & Anderson (2004: 347) , pro parte, non Valeton (1909: 48): quoad Clemens & Clemens 50779.

Timonius polyneurus sensu Beaman & Anderson (2004: 348) , pro parte, non Valeton (1909: 59): quoad RSNB 184.

Tree to 7.6 m tall; trunk dbh and bark unknown. Stipules lanceolate, plane to slightly 2–ridged, imbricate. Leaves opposite; petioles 3–20 mm long, 1–2.5 mm in diam.; blades narrowly elliptic, 8–15 × 3.4–5.4 cm, base cuneate, apex cuspidate, margins plane, chartaceous, lower surface sparsely to densely appressed-pubescent, upper surface slightly to conspicuously bullate; secondary veins 8–12 on each side of the midrib, 3–20(–26) mm apart from each other; tertiary veins not prominent on lower surface. Inflorescences: female plants with a solitary flower per inflorescence, peduncle length unknown, peduncular bracts triangular, 2.5–4 × ca. 1.5 mm; male plants with 2–3 flowers per inflorescence, peduncles ca. 1.8 cm long. Calyx lobes in female flowers 4, broad-triangular (length about the same as basal width), 1.5–2.5 mm long, densely pubescent outside; in male flowers 4, broad-triangular, 1.5–2 mm long, densely pubescent outside. Corolla in female flowers unknown; in male flowers with tube ca. 8 mm long, mature diam. unknown, densely pubescent outside, lobe number unknown, lanceolate, ca. 4 mm long, densely pubescent outside. Fruits globose to ellipsoid, 5–8 mm in diam., glabrous to subglabrous; peduncles 1.2–1.4 cm long, sparsely to densely pubescent; persistent calyx lobes broad-triangular, 1.5–2.5 mm long.

Etymology: —The specific epithet refers to the bullate lamina of this species.

Distribution: —Only known from Kinabalu Park and Mount Trus Madi.

Habitat: —Lower to upper montane forest.

Proposed conservation status: —The conservation status assessed for T. bullatus using GeoCat was Near Threatened ( IUCN 2001). Although its estimated AOO (28 km 2) is within the Endangered range, there is no evidence of decline or fluctuations in EOO, AOO, number of locations, and number of mature individuals. Most known populations occur within Kinabalu Park, which is an important conservation area. However, its narrow distribution renders this species vulnerable to random catastrophic events.

Additional specimens examined (paratypes): — BORNEO. Sabah: Kinabalu Park, Gurulau Spur, 2130–2740 m , 6 December 1933 (♂ plant), Clemens & Clemens 50779 (K, L); Kamborangoh, 19 June 1933 (♂ plant), Carr SF 27671 ( SING); Layang-Layang , 22 February 2011 (♀ plant), Van der Ent et al. SNP 20259 ( SNP); Menteki Ridge , 28 January 2011 (♀ plant), Van der Ent et al. SNP 18706 ( SNP); Mount Tambuyukon , 5 May 2011 (♀ plant), Van der Ent et al. SNP 27152 ( SNP); power station , 24–26 October 1981 (♀ plant), Sato et al. UKMS 1421 ( SAN) . Tambunan, Mount Trus Madi , above Sungei kidukaruk, 13 November 1964 (♀ plant), George SAN 41852 (K, SAN) ; Trus Madi Range , 1940 m , 8 March 1995 (♂ plant), Wong WKM 2638 (L, SAN), 1940 m , 8 March 1995 (♀ plant), Wong WKM 2644 (L, SAN) .

Figures

FIGURE 2. A. Female inflorescences of Timonius beamanii, Dolois SNP 16277 (SNP). B. Female inflorescence of T. borneensis, Wong WKM 3231 (BRUN). C. Male inflorescences of T. beamanii, Jusimin 560 (SNP). D. Male inflorescence of T. borneensis, Talib SAN 84768 (SING). E. Leaves of T. bullatus, Chew et al. RSNB 184 (SAN). F. Leaves of T. polyneurus, Teysmann 8361 (K). G. Solitary fruits of T. bullatus, Chew et al. RSNB 184 (SING). H. Infructescences of T. leopoldii, Leopold SAN 89494 (SAN). Scale bars: 1 cm. [Photos: A, C, D, E, and G, J. Chen; B, F, and H, K.M. Wong]