Hydnophytum formicarum Jack

1. Hydnophytum formicarum Jack View in CoL — Fig. 1 View Fig , 2 View Fig

Hydnophytum formicarum Jack (1823) 124; DC. (1830) 451; G.Don (1834) 547; D.Dietr. (1839) 459; Endl. (1838) 539; Hassk. (1844) 110; Korth. (1851) 227; Miq. (1855) 309; Hassk. (1866) 172; Miq. (1869) 257; Benth. & Hook.f.(1873) 132;Kurz (1877) 8; Hook.f. (1881) 194; Becc.(1885) 159; Ridl. (1923) 172; Pit. (1924) 406; Craib (1934) 223.

— Type: Jack s.n. (no specimen known to have existed), Sumatra, Nias Is. Lectotype selected here: Rumphius, Herb. Amboin. 11, 16 (1750) 119, t. 55: 1 ( Nidus formicarum niger ). Epitype nominated here: Meijer 4602 (L), Sumatra,Mt Sago.

[ Nidus formicarum niger Rumph. (1750) 119, t. 55: 1].

Lasiostoma formicarum (Jack) Spreng. (1825) 423.

Hydnophytum montanum Blume (1826) 956; DC. (1830) 451; Miq. (1855) 309; Becc. (1884) 125. — Many syntypes: Blume (BO), Java, syn. nov.

Hydnophytum sumatranum Becc.(1884) 124;(1885) 137,t. 39:1–5. — Type: Beccari s.n. (FI), Indonesia, Sumatra,Padang,Air Mancur,Aug.1878, syn. nov.

Hydnophytum amboinense Becc.(1884) 124; (1885) 138,t. 32:1–7. — Nidus formicarum niger Rumph. (1750) 119, t. 55: 1a. — Hydnophytum formicarum auct. non Jack: Miq . (1855) 308 p.p. — Type: Beccari 5530 (FI, K), Indonesia, Ambon, syn. nov.

Hydnophytum gaudichaudii Becc.(1884) 124;(1885) 139,t. 35: 1–9. — Hydnophytum inerme (Gaudich.) Bremek. ex Holthuis & H.J.Lam (1942) 245. — Myrmecodia inermis auct. non DC. (1830) 450: Gaudich. in Freyc. (1830) 472, t. 95, 96:2–11 (excl. all synonymy);G.Don (1834) 547; D.Dietr. (1839) 485. — Type: Gaudichaud s.n. (G, P), Indonesia, Waigeo, Rawak Island, syn. nov.

Hydnophytum selebicum Becc.(1884) 125;(1885) 157,t. 39:6–12. — Type: Beccari s.n. (FI), Indonesia, Sulawesi, Kendari, syn. nov.

Hydnophytum coriaceum Becc.(1884) 125; (1885) 158, t. 41. — Type: Beccari 661 (FI), Borneo, Sarawak, syn. nov.

Hydnophytum andamanense Becc. (1885) 156, t. 38: 11–18. — Type: Kurz s.n. (CAL not seen, P), Andaman Islands, syn. nov.

Hydnophytum formicarum montanum α typicum Becc . (1885) 159, t. 47: 1–11. — Hydnophytum montanum Blume (1826) 956; DC. (1830) 451; Hassk.(1844) 110;G.Don (1834) 547; D.Dietr. (1839) 459; Miq. (1855) 309 (excl. syn. Rumphius); (1869) 266. — Type: Blume s.n. (L, P), Indonesia, Java, Buitenzorg, syn. nov.

Hydnophytum formicarum montanum β latifolium Becc . (1885) 160. — Hydnophytum montanum var. latifolia [sic] Miq. (1869) 256. — Type: Van Hasselt s.n. (L), Indonesia, Java, Lebak, syn. nov.

Hydnophytum formicarum montanum γ longifolium Becc . (1885) 161, t. 49: 1–5 (sphalm. Hydnophytum montanum forma longifolium l.c. p. 340); Hydnophytum montanum forma,Miq.(1869) 256; Hydnophytum formicarum Jack (1823) 124, excl. Nidus formicarum niger Rumph. — Type: Korthals s.n. (L), Indonesia, Sumatra, syn. nov.

Hydnophytum formicarum montanum δ minor Becc . (1885) 161, t. 50: 1–8; Hydnophytum montanum auct. non Blume: Becc. (1884) 125. — Type: Zollinger 2607 (FI), Indonesia, Java, syn. nov.

Hydnophytum formicarum montanum ε borneense Becc. (1885) 162, t. 50: 9–18; Hydnophytum borneense Becc. (1884) 125. — Type: Beccari PB 711 (FI), Borneo, Sarawak, syn. nov.

Hydnophytum formicarum montanum ζ buxifolium Becc. (1885) 163, t. 47: 12–16. — Hydnophytum montanum ( Celebicum ) Miq. (1869) 266 in syn. — Type: Forsten s.n. (L), Indonesia, Sulawesi, Tondano, syn. nov.

Hydnophytum formicarum montanum η cochincinense Becc. (1885) 163, t. 49: 6–10. — Hydnophytum blumei Becc. (1884) 125, p.p.; Pit. (1924) 407. — Type: Pierre 51 (A, BM, FI, K, L, P), Vietnam, BaRia Province, Dinh mountain, Mar. 1869, syn. nov.

Hydnophytum formicarum montanum θ lucidum Becc. (1885) 164, t. 49: 11–15. — Hydnophytum blumei Becc. (1884) 125, p.p. in clavi. — Type: Beccari PB 3671 (FI), Borneo, Sarawak, syn. nov.

Hydnophytum formicarum blumei Becc. (1885) 164, t. 48: 1–8. — Hydnophytum formicarum auct. non Jack: Blume (1826) 956. — Hydnophytum ellipticum Blume Herb. (according to Miq.) ex Becc. (1885) 164, in syn. — Hydnophytum montanum latifolium Miq. (partim) (1869) 257. — Hydnophytum montanum auct. non Blume:Burck (1884) 16, t. 4: 5. — Hydnophytum blumei Becc. (1884) 125, p.p. in clavi. — Type: Blume s.n. (L), Java, Buitenzorg, syn. nov.

Hydnophytum formicarum dubium Becc. (1885) 165, t. 48: 9–11, t. 49: 16–19, 51, 52: 2. — Hydnophytum blumei Becc. (1884) 125, p.p. in clavi. Syntypes: Griffith (CAL not seen), Malacca, and Gaudichaud (L not seen), Singapore, syn. nov.

Hydnophytum formicarum siamense Becc. (1885) 167, t. 48: 12–17; Pit. (1924) 407. — Type: Pierre 1348 (P), Vietnam, Phu-Qouc island, syn.nov.

Hydnophytum formicarum zollingerii Becc.(1885) 167,t. 57:17–22. — Type: Zollinger 659 (A, G, P), Java, syn. nov.

Hydnophytum nitidum Merr. (1907) 307. — Type: Merrill 6181 (PNH presumed lost), Philippines, syn. nov.

Hydnophytum intermedium Elmer (1911) 1039. — Type: Elmer 10782 (E, L), Philippines, May 1909, syn. nov.

Hydnophytum orbiculatum Elmer (1913) 1860. — Type: Elmer 15583 (BM, BO, F, FI, G, GH, L, P, UC, W), Philippines, Dec. 1915, syn. nov.

Hydnophytum leytense Merr. (1913) 390. — Type: Wenzel 45 (G), Philippines, syn. nov.

Hydnophytum membranaceum Merr.(1915) 143. — Type: Merrill 3720 (PNH presumed lost), Philippines, syn. nov.

Hydnophytum mindorense Merr. (1915) 143. — Type: Merrill 6182 (PNH presumed lost), Philippines, syn. nov.

Tuber globose to oblate, to 60 cm across; surface smooth to rugose, grey to brown. Roots confined to substrate side of tuber, occasionally numerous and throughout, then becoming ± spinose. Entrance holes lipped or not, to 1 cm across. Stems few to many, sparsely to densely branched; internodes 0.5–5 by 0.2–0.6 cm. Lamina usually lanceolate-elliptic, occasionally obovate or rhomboid, rarely orbicular; 5 by 2, 8 by 1.5, to 14.5 by 7 cm; apex rounded to round-acute; base cuneate, tapering to petiole; midrib prominent below; veins 3–10 oblique; chartaceous to leathery, brittle. Petiole 0–1.5 cm; stipules 0.1–0.2 cm, triangular, caducous. Inflorescence sessile to sunken, paired, axillary. Flowers [12] not heterostylous. Calyx to 1 mm. Corolla tube 1–3 mm, lobes 0.7–1.5 mm, with a ring of hairs below level of mouth. Anthers 1 mm, at mouth of tube. Pollen 3-colporate, 60 (50–75) μm, finely reticulate, vesicles and pores small. Stigma bifid, above level of anthers. Fruit ovoid, to 8 by 5 mm, rarely pubescent, red when ripe. Pyrenes ellipsoid-ovoid, to 2.5–3.5 by 1 mm; apex acute to acuminate, base rounded.

Ecology & Habitat — Mangrove swamp, savannah forest, especially common in heath forest growing on nutrient-poor soils; sea level to 1 500 m. Tuber nearly always inhabited by ants, and usually by Philidris cordata . Rare in many Indonesian islands.

Distribution — Andaman Islands, Burma, Thailand, Vietnam, Cambodia, Sumatra, Peninsular Malaysia, Borneo, Java, Philippines, Sulawesi, Lesser Sundas and Moluccas; it has been collected once from Waigeo Island, but is apparently absent from the New Guinea mainland.

Conservation status — Least Concern (LC). Whilst probably Vulnerable in some parts of its range, this taxon is found throughout the Indonesian archipelago. Other information: EOO 8.5 million km 2.

Typification — Jack’s original specimen, if it existed, was lost with the ship ‘HMS Fame’, which caught fire in the Indian Ocean (Van Steenis-Kruseman 1950); however, he also cited Rumphius’ illustration (1750) of Nidus formicarum niger ( Fig. 2 View Fig ). Since this latter illustration comprises part of the ‘original material’, it must automatically stand as the lectotype (Art. 9.9 in Turland et al. 2017). However, in view of the variable nature of H. formicarum this type is of no practical use – there being over 3 000 km between the type locality cited by Jack (Nias Island, Sumatra) and the lectotype (Ambon). No material is available from Nias, and a specimen from mainland Sumatra has therefore been selected as an epitype (Art. 9.7), to serve as a discriminating element. Geographically, this is the closest specimen that provides a good match to the original description by Jack.

Since there is no conflict within the type material of the various synonyms, we have not lectotypified any of the material since we feel that considerable alteration may occur to the broad species concept we have proposed here, once more methodical collecting has been undertaken in Indonesia.

Notes — A widespread and variable species, characterised by its lanceolate-elliptic leaves with a blunt apex.The concept of H. formicarum is broadly defined here, incorporating 15 former species and 12 forms and varieties. Neither Valeton nor Merrill and Perry investigated the Indonesian species of Hydnophytum , and Beccari is the only author who had extensive field knowledge of these plants in the islands west of New Guinea. The many forms and varieties that Beccari described, however, do not appear to be helpful in understanding the genus in Indonesia.

There are several island forms with much smaller leaves, and the most problematic region centres around the southern Philippines and the northern Moluccas, where this species and H. moseleyanum [14] are both found. On mainland New Guinea this species appears to be replaced by H. petiolatum [11]. In Eastern Borneo there is an exceptionally narrow-leafed species, H. puffii [2], that we have recognised as distinct since it appears to be co-extensive with H. formicarum .

Beccari (1885: 164) synonymised the name H. ellipticum under his H. formicarum blumei (which was in turn a renaming of his own H. blumei ), citing it as being a specimen in the Blume Herbarium seen by Miquel. There are no further details of this in sched. name, and we have seen no specimen. The name H. ellipticum [7] was later used by Merrill and Perry.