Syzygium balgooyi Brambach, Byng & Culmsee, 2017

Brambach, Fabian, Byng, James W. & Culmsee, Heike, 2017, Five new species of Syzygium (Myrtaceae) from Sulawesi, Indonesia, PhytoKeys 81, pp. 47-78 : 51-56

1. Syzygium balgooyi Brambach, Byng & Culmsee sp. nov. Figures 1 , 2 , 8

Eugenia "spec. BB" ( Koorders 1898, 173, 459, Koorders-Schumacher 1914, 95).

Myrtaceae " sp. 10" p.p. ( Culmsee and Pitopang 2009, see also 2017 (Erratum), Culmsee et al. 2011).

Diagnosis.

Syzygium balgooyi is characterised by long, elongate-clavate flowers, a character otherwise only known from the morphologically similar Syzygium schumannianum (Nied.) Diels (1922, 402) from New Guinea and the Maluku Islands. Syzygium balgooyi differs from that species by its smooth (vs prominently longitudinally ridged) hypanthium and fruit and by the hypanthium rim which remains entire after anthesis (vs apically splitting into 4 recurving lobes). Floral formula B1 Bt2 K4* C4* A∞* Ĝ (2)┼ Vx∞.

Type.

INDONESIA. South Sulawesi (Sulawesi Selatan), Kab. Luwu Timur, Kec. Nuha, Between Soroako and Nickel plant site, c. 2°33'S, 121°22'E, 500 m, 10 Jul 1979: van Balgooy 3956 (flowers; holotype L [L.2517558]! [spirit collection L 0771145] [wood sample L 0708624], isotype A [A01143212]!) .

Description.

Trees, up to 37 m tall, diameter at breast height ≤ 65 cm, trunk straight, ≤ 20 m tall, often fluted and with buttresses ≤ 3 m tall and 1 m out. Outer bark pale brown to bright red, peeling off in small or large sheets, inner bark dark red, usually paler towards inside, sometimes with little watery red sap, wood very hard and heavy, sapwood cream, clearly separated from the dark reddish brown heartwood. Young branchlets 1-2 × 1.5-4 mm, strongly flattened, the flat sides usually with two lateral, rounded ridges leading to the petioles and one central ridge continuing into the next internode, often resinous when dry, epidermis green, drying dusky red to reddish black and usually smooth; becoming terete, bark drying red to dark reddish brown, finely flaking and with conspicuous flaking remnants of epidermis.

Leaves (sub-)opposite. Petioles 2-12 × 1-3.5 mm, flat and sometimes narrowly winged above, rounded or keeled beneath, drying reddish black and smooth. Blades (4-) 7-11.5 (-16) × (1.5-) 3-5 (-9) cm, ratio (1.2-) 1.8-2.7 (-5), (narrowly) elliptic, obovate, or oblanceolate, base cuneate and attenuate at the very base or obtuse to rounded, apex usually rounded or obtuse, sometimes emarginate or acute, margin slightly to strongly revolute; (thick-)coriaceous, purple, pink, or reddish when young, fresh to dark glossy green above, paler glossy green beneath, drying dull to shiny, often resinous after drying, reddish brown to reddish black above, reddish brown to very dusky red beneath. Midrib channelled above, prominent and rounded or keeled, drying reddish black and smooth beneath. Secondary vein pairs (9-) 11-14 (-16), 4-12 (-15) mm apart, ± faint and lighter red than the lamina above, ± prominent and darker than the lamina beneath; intersecondary veins present. Tertiary veins sup-parallel near the midrib, reticulate towards the margins, ± faint above, faint or prominulous and darker than the lamina beneath. Inner intramarginal vein 1-5 mm from the leaf margin, ± looping; outer intramarginal vein <1 mm from the leaf margin, often seemingly absent from leaf margin.

Inflorescences terminal and often in axils of distal leaf pair, rather dense panicles, 5-10 cm long, peduncles 1-6 cm long, axes subangular or rounded, flattened, resinous after drying. Bracts c. 3 mm long, linear, pellucid-dotted, caducous; bracteoles 2 per flower, sometimes seemingly 4 (by contraction of the ultimate inflorescence axes?), 1 mm long.

Flowers 5-15 per inflorescence, within the panicles in monads or clusters of 2-4, 4-merous, anthopodium absent, c. 20-30 mm in diameter at anthesis, mature buds 20-30 × 3-6 mm. Hypanthium 20-30 × 5-7 mm, elongate-clavate, yellowish green, drying smooth black, hypanthium rim 15 mm long, glandular inside. Calyx lobes c. 2 × 2 mm, claw- or hood-shaped. Petals c. 4 × 3 mm, ± obovate, pale green. Stamens c. 100, filaments 10-20 mm long, pale green, anthers c. 0.5-0.8 mm long, ellipsoid, yellow. Ovary bilocular, locules surrounded by spongy tissue, ovules c. 15-20 per locule, ascending, ± arranged in 2 longitudinal rows. Style 25-35 mm long, pointed.

Fruits 1-2-seeded, 27-33 × 12-16 mm, ampulliform, yellowish green (immature?), drying black, smooth or slightly warty, pericarp c. 1 mm thick, leathery when fresh, ± woody when dried, hypanthium rim 8-12 mm long, 4-5 mm in diameter.

Seeds 13-15 × 9-10 mm, ellipsoid, testa cartilaginous, attached to the pericarp, cotyledons free from the testa, ± half-globose, minutely verrucose, facing surfaces undulate.

Etymology.

The species is named after Max Michael Josephus van Balgooy (*1932), botanist and authority on Southeast Asian plant taxonomy, identification, and biogeography. He collected over 900 specimens during a Dutch-Indonesian expedition to Sulawesi in 1979, among them the type specimen of this species. We enjoyed the privilege of learning from Max during several stays at the herbarium in Leiden and receiving his help with the identification of our specimens collected in Central Sulawesi.

Phenology.

Flowering specimens have been encountered throughout the year without any apparent association with geography or climate. Fruiting specimens have been recorded in May (de Vogel 5413) and September (sight record by FB).

Distribution and habitat.

Syzygium balgooyi is restricted to Sulawesi and widespread across the island (Figure 2 ). The species occurs on a variety of geological substrates, namely volcanic rocks on the Northern Peninsula, acid plutonic rocks and schists in the Central Sulawesi Mountains (see Brambach et al. 2016 for definition), alluvial deposits at the base of the Southern Peninsula, and ultramafic rocks on the Eastern and Southeastern Peninsulas. According to the information on specimen labels it grows in primary forests, both virgin and disturbed, over a wide elevational range (c. 100-2000 m). There, it forms part of the canopy layer, sometimes co-dominant (van Balgooy and Tantra 1986), but usually with scattered individuals ( Culmsee et al. 2011, Brambach et al. in press).

Conservation status.

The AOO of 64 km² would place Syzygium balgooyi in the category “Endangered” (EN), despite its wide distribution in Sulawesi (Figure 2 ) as reflected by the estimated EOO of 94 451 km². The species has been found in a wide variety of habitats, including montane forests at different elevations, with scattered individuals or even co-dominant at times (see Distribution and Habitat above). We have no reason to believe that it is scarce throughout its range. Rather, we argue that the small estimated AOO is an artifact due to the generally low collection rate in Sulawesi and the real geographic distribution does not meet criterion B for any of the “threatened” categories of IUCN (2012). However, although we lack real evidence about possible changes in population size over time, using the Global forest change website ( Hansen et al. 2013), we detected deforestation activities at or near five of the 18 collection localities (28%) of S. balgooyi . Given that the species is only recorded from old-growth forest habitats, we consider this a loss of suitable habitat, slightly below the 30% threshold for the “Vulnerable” category. Notably, all deforestation took place in places with relatively easy access and at low elevations. Thus, given (1) the relatively large EOO of S. balgooyi , (2) its apparent wide ecological niche, (3) its frequency of occurrence, (3) the low collection rates in Sulawesi, and (4) the loss of suitable habitat, we propose a preliminary extinction risk assessment of "Near Threatened" (NT) following the IUCN Red List Categories and Criteria ( IUCN 2012).

Vernacular names.

Cenke hutan (= forest clove, Indonesian, de Vogel 2651), Jambu (general name for Syzygium , Indonesian, NIFS bb 33081), Rokobako (NIFS Cel./II-385), Tambeanitu (Bahasa Behoa, Brambach et al. 1047, 1083, 1290, 1316), Wawahuling (Bahasa Tondano, Koorders 182 51, see Koorders 1898, 173, 459).

Notes.

Among Syzygium species of Sulawesi, S. balgooyi can be recognised in the field by its tall stature (Figure 1a ), the bright red bark that peels off in thin sheets (Figure 1d, g ) and the rather thick, usually obovate or oblanceolate leaves with ± rounded tips (Figure 1b-c , 8a-e ). Dry specimens are recognisable by the dark reddish brown twigs bearing thick black flakes of the peeling epidermis and the very dark upper leaf surface with contrasting paler veins.

Leaf size and thickness are quite variable (Figure 8a-e ), as can be expected for a species with such a wide ecological distribution. Small leaves are usually found at higher elevations, whereas thick leaves seem to be associated with ultramafic soils. While the extreme forms suggest that several distinct species are involved, when taking into account all the available material, intermediate states connecting the extremes appear. We therefore prefer to treat this as one species with the vegetative parts morphologically variable.

Syzygium balgooyi and S. schumannianum are difficult to separate in vegetative state. S. balgooyi usually has leaves with rounded, obtuse, emarginate, or acute tips, whereas they are shortly acuminate in S. schumannianum , but there are exceptions in both species. Flowers and fruits of the two species also share the same structure but there are two important differences which we consider sufficient to warrant specific separation: Firstly, as indicated by the original name Eugenia neurocalyx Schumann nom. illeg. (in Schumann and Hollrung 1889, 90), the outer surface of the hypanthium in S. schumannianum bears prominent “nerves”, i.e. longitudinal ridges (Figure 1l-m ). These ridges are already visible in young flower buds and remain present until the fruiting stage. Single, very faint ridges may appear in flowering specimens of S. balgooyi (seen in de Vogel 2651) but in the bulk of the material at our disposition, flower buds, flowers, and fruits are completely smooth (Figure 1j-k ). Furthermore, in S. balgooyi the stamens are arranged in a ring along the upper margin of the hypanthium rim, which remains entire through the fruiting stage (Figure 1j-k ). In S. schumannianum , the apical portion of the woody hypanthium rim splits into 4 outward-curving lobes and the stamens are arranged in a small area at the inside of each lobe near its tip (Figure 1l-m , Schumann and Hollrung 1889, Merrill and Perry 1942).

The wood of S. balgooyi is used for construction in North Sulawesi, but is not water-resistant ( Koorders 1898, 173). Several collectors describe it as very hard and heavy. Mean wood density, as measured from 13 wood cores in LLNP was 0.74 g cm-1 ( ± 0.05 SD).

Additional specimens examined

(Paratypes). INDONESIA. North Sulawesi (Sulawesi Utara) : Kab. Minahasa, Kec. Kakas, Old-growth forest Pinamorongan, c. 1°08'N, 124°56'E (" Noord-Celebes, Residentie Menado, Pinamorongangebergte bij Kakas "), 500 m, 30 Jan 1895: Koorders 18251 (sterile; L [L.2517502]! [L.2535743]!) .

Kota Bitung, Kec. Ranuwulu, southern part of Wiau Forest Reserve (Hutan Lindung G. Wiau), base of Mt Klabat, c. 1°28'N, 125°03'E, 400 m, 1 Nov 1973: de Vogel EF 2651 (flowers; L [L.2535729]! [L.2535730]! [wood sample L 0204047]).

Central Sulawesi (Sulawesi Tengah), LLNP: Kab. Poso, Kec. Lore Utara, west slope of Mt Rorekautimbu , c. 1°16'S, 120°16'E, 1700 m, 15 May 1979: van Balgooy MMJ 3371 (sterile; L [L.2535697]!) .

Kab. Poso, Kec. Lore Utara, west slope of Mt Rorekautimbu, c. 1°16'S, 120°17'E, 2000 m: 5 May 1979: Tantra IJM 1589 (sterile; L [L.2517457]!), & 1592 (sterile; L [L.2535672]!); ibid. loco, 17 May 1979: de Vogel EF 5413 (fruits; BO [BO-1686561], K [K001024419]!, L [L.2517562]! [L.2517563]!, [wood sample L 0708565]).

Kab. Poso, Kec. Lore Utara, 4 km E of Wuasa, c. 200 m N of Rumuku waterfall, tree-inventory plot Torongkilo, 1°24.9'S, 120°16.7'E, 1450 m, 6 Mar 2012: Brambach F, Mangopo H, Firdaus, Faber M, Tiranda R 1478 (sterile; BO [BO-1938440]!, CEB, L!) & 1564 (flower buds; BO [BO-1938441]!, CEB, K [K000993483]!) & 1583 (sterile; GOET [GOET020022]!).

Kab. Poso, Kec. Lore Tengah, 9 km NW of Bariri, 100 m E of climate tower, tree-inventory plot Bariri NE, 1°39.4'S, 120°10.5'E, 1400 m: Jul 2007: Culmsee H y896 (sterile; CEB, L!); ibid. loco, 21 Aug 2011: Brambach F, Mangopo H, Firdaus, Faber M, Tiranda R 0861 (sterile; BO [BO-1938438]!, CEB, GOET [GOET020025]!) & 0889 (sterile; BO [BO-1938439]!, CEB, L!) & 0907 (sterile; CEB, GOET [GOET020024]!, L!).

Kab. Poso, Kec. Lore Tengah, 9 km NW of Bariri, 80 m south of climate tower, tree-inventory plot Bariri S, 1°39.5'S, 120°10.4'E, 1400 m, Jul 2007: Culmsee H 1459 (sterile; CEB, GOET [GOET020006]!) & 1495 (sterile; BO [BO-1938457]!, CEB); ibid loco, Jul 2007: Culmsee H r808 (sterile; CEB, GOET [GOET020008]!).

Kab. Poso, Kec. Lore Tengah, 7 km WNW of Hanggira, E flank of Mt Dali, tree-inventory plot Pantakleabae, 1°42.0'S, 120°09.0'E, 1950 m: 3 Mar 2011: Culmsee H, Brambach F, Mangopo H, Firdaus, Faber M, Tiranda R r2162 (sterile; CEB, GOET [GOET020021]!) & r2254 (sterile; BO [BO-1927087], CEB, GOET [GOET020023]!); ibid. loco, 30 Mar 2011: Brambach F, Mangopo H, Firdaus, Faber M, Tiranda R 0038 (sterile; BO [BO-1926965], CEB, GOET [GOET020027]!, K [K000993482]!, L!) & 0058 (sterile; BO [BO-1926969]!, [BO-1926970]!, CEB, GOET [GOET020033]!) & 0082 (sterile; BO [BO-1938382]!, CEB, GOET [GOET020030]!, L!) & 0097 (sterile; CEB, GOET [GOET020029]!, L!); ibid. loco., 23 Jan 2012: Brambach F, Mangopo H, Firdaus, Faber M, Tiranda R 1333 (sterile; CEB, GOET [GOET020020]!, L!).

Kab. Sigi, Kec. Kulawi, 2.4 km ENE of Toro, NE edge of Pono Valley, tree-inventory plot Pono, 1°29.7'S, 120°03.4'E, 1050 m: 4 Aug 2006: Culmsee 125 (sterile; BO [BO-1938456]!, CEB, L!) & 209 (sterile; CEB, K [K000993486]!); ibid. loco, Jul 2007: Culmsee r211 (sterile; CEB, GOET [GOET020009]!).

Kab. Sigi, Kec. Kulawi Selatan, 4 km E of Watukilo, following footpath to Mt Tokepangana, tree-inventory plot Tokepangana, 1°36.9'S, 120°04.4'E, 850 m, 16 Apr 2011: Brambach F, Mangopo H, Firdaus, Faber M, Tiranda R 0176 (sterile; BO [BO-1926967]!, CEB, GOET [GOET020028]!, L!) & 0206 (sterile; BO [BO-1926968]!, CEB) & 0283 (sterile; BO [BO-1926973]! [BO-1926974]!, CEB, GOET [GOET020032]!, K [K000993481]!, L!) & 0319 (BO [BO-1926934]!, CEB) & 0332 (BO [BO-1926966]!, CEB) & 0363 (BO [BO-1926919]!, CEB).

Kab. Sigi, Kec. Kulawi Selatan, 4 km ENE of Watukilo, 400 m N of Mboe River, tree-inventory plot Rantena, 1°36.2'S, 120°04.5'E, 700 m: 17 Jun 2011: Brambach F, Mangopo H, Firdaus, Faber M, Tiranda R 0466 (sterile; BO [BO-1938383]!, CEB, GOET [GOET020031]!); ibid. loco, 21 Jun 2011: Brambach F, Mangopo H, Firdaus, Faber M, Tiranda R 0628 (sterile; CEB, GOET [GOET020026]!, L!).

Kab. Sigi, Kec. Nokilalaki, 4.3 km SSW of Tongoa, NW flank of Mt Nokilalaki, ca. 400 m S of Shelter 2, tree-inventory plot Nokilalaki 2, 1°14.6'S, 120°09.1'E, 1850 m, Sep 2007: Culmsee 2923 (sterile; CEB, L) & 3075 (sterile; BO [BO-1938463]!, CEB).

Kab. Sigi, Kec. Nokilalaki, 4.3 km SSW of Tongoa, NW flank of Mt Nokilalaki, ca. 500 m SSE of Shelter 2, tree-inventory plot Nokilalaki 1, 1°14.7'S, 120°09.2'E, 1900 m, Aug 2007: Culmsee 2636 (sterile; CEB, L!) & 2641 (sterile; BO [BO-1938462]!, CEB, GOET [GOET020007]!) & 2721 (sterile; CEB, K [K000993487]!).

Kab. Tojo Una-una, Kec. Ulubongka. N slope of Mt Katopas , 1°9.8'S, 121°26.9'E, 1100 m, 4 Sep 2014: Sight record by F Brambach (photograph Figure 1f ) .

West Sulawesi (Sulawesi Barat): Kab. Mamasa. Kec. Mamasa, near Osango c. 2°56'S, 119°19'E (" Celebes en Ond. Boven Binoeang, ca. Osango") , c. 1500 m, 1 Jul 1939: Netherland's Indies Forest Service (NIFS) bb 28293 (sterile; L [L.2529832]!) .

South Sulawesi (Sulawesi Selatan): Kab. Luwu, Kec. Ponrang, near Kampung Tampa , c. 3°11'S, 120°13'E (" Celebes en Ond. Palopo, Bakka, Kampoeng Tampa") , c. 100 m, 15 Sep 1941: NIFS bb 33081 (flowers; L [L.2535805]!).

Kab. Luwu Timur: Kec. Malili, Ussu, c. 2°36'S, 121°06'E (" Selebes, Malili, Oesoe): c. 300 m, 13 Jul 1931: NIFS Cel./II-385 (flower buds; L [L.2535679]!); ibid. loco, c. 400 m, 19 Jun 1934: NIFS Cel./II-293 (sterile; L [L.2517541]!) ; ibid. loco, 100 m, 28 Mar 1941: NIFS bb 32595 (sterile; BO [BO-1304600], L [L.2517463]!) .

Kab. Luwu Timur, Kec. Wasuponda, Larona, c. 2°45'S, 121°20'E, 500-1000 m (" Celebes. Goud. Celebes, Ond. afd. Malili, nabij La Rona "), n.d.: NIFS bb 1843 (sterile; L [L.2535842]!) & bb 1895 (sterile; L [L.2535843]!) .

Kab. Luwu Timur, Kec. Nuha, Hills W of Soroako, c. 2°31'S, 121°19'E, 550 m, 17 Jun 1979: van Balgooy MMJ 3767 (old inflorescences; L [L.2535910]! [wood sample L 0708626]).

Figures

Figure 1. Morphological characters of Syzygium balgooyi and S. schumannianum. Syzygium balgooyi (a-k): a c. 20 m tall trunk b upper leaf surface; c lower leaf surface d bark with slash e ridged shoot apex with subopposite leaves f flowers at different stages during anthesis and fruit g trunk base with steep narrow buttresses h inflorescence with flower buds i shoot with young leaves j dried flowers before and during anthesis and longitudinal section of flower k dried fruit and longitudinal section of fruit showing two cotyledons. Syzygium schumannianum (l-m): l dried flowers before and during anthesis m dried fruit. a-b and h-i Brambach et al. 1564 c Brambach et al. 0861 d-e Brambach et al. 0628 f sighting on Mt Katopas by FB g Brambach et al. 0889; j holotype van Balgooy 3956 [L. 2517558] k de Vogel 5413 [L. 2517563] l Wiakabu et al. LAE 50571 [L. 2535534] m Brass 13610 [L. 2524420]. All scale bars: 1 cm.

Figure 2. Distribution map of Syzygium balgooyi in Sulawesi. Collecting localities are shown as yellow dots; Lore Lindu National Park is indicated by a black line. Map created with QGIS (QGIS Development Team 2016) using the digital elevation model of Jarvis et al. (2008).

Figure 8. Leaves of all new species described. Variation of Syzygium balgooyi (a-e), S. contiguum (f), S. devogelii (g), S. eymae (h), and S. galanthum (i). a Brambach et al. 0283 b Brambach et al. 0681 c Brambach et al. 1333 d de Vogel 5413 [L. 2517563] e Culmsee r 2162 f Culmsee r 463 g Brambach et al. 0818 h Eyma 3624 [L. 2535689] i Brambach et al. 0533. Scale bar: 10 cm, valid for all leaves.