Humbertacalia pyrifolia (Bojer ex DC.) C. Jeffrey

Rabarimanarivo, Marina N., Callmander, Martin W. & Calvo, Joel, 2023, Synopsis of Humbertacalia (Compositae), a genus endemic to Madagascar and Réunion, Adansonia (3) 45 (7), pp. 93-113 : 104-106

8. Humbertacalia pyrifolia (Bojer ex DC.) C. Jeffrey

( Fig. 4 )

Kew Bulletin 47 (1): 83 ( Jeffrey 1992).

Mikania pyrifolia Bojer ex DC. , Prodromus Systematis Naturalis Regni Vegetabilis 5: 195 ( Candolle 1836).

— Typus: Madagascar. Province de Betsilou, s.d., fl., Bojer s.n. (holo-, G-DC [ G00323809 ]!) ( Fig. 4 ).

Senecio curvatus Baker , Journal of the Linnean Society, Botany 20: 190 ( Baker 1883).

— Typus: Madagascar. Central Madagascar , X.1881, fl., Baron s.n. (holo-, K [ K000377693 ]!) .

Vernonia asclepiadea Drake , Bulletin de la Société botanique de France 46: 238 ( Drake 1899).

— Typus: Madagascar. Analamanga Region [Prov. Antananarivo], Ost Imerina, Andrangoloaka , [19°02’S, 47°55’E], XI.1880, fl. & fr., Hildebrandt 3626 (lecto-, designated here, P [ P00727176 excl. branch on the left]!; isolecto-, G [ G00412688 , G00412689 ]!, P [ P00727177 ]!) .

ICONOGRAPHY. — Humbert (1963: 761, fig. 139, 3-4, sub Senecio curvatus ).

ETYMOLOGY. — The epithet pyrifolia refers to the leaves similar to those of Pyrus L. ( Rosaceae ).

VERNACULAR NAMES. — “Anadraisoa” (Benoist 1269); “Hanidraisoa” (Alleizette 809M); “Kimboimboy lahy” (Kotozafy 311); “Rangasoalahy” (Réserves Naturelles 6337).

DISTRIBUTION AND ECOLOGY. — Humbertacalia pyrifolia is endemic to Madagascar where it is widespread from Tsaratanana and Marojejy (Diana and Sava Regions) in the north to Andohahela (Anosy Region) in the south. It occurs in humid, subhumid and montane bioclimates, in sclerophyllous woodland, remnant medium altitude moist evergreen forest or montane ericoid thicket at high elevation, especially on gneiss and granite substrate (inselberg rock face) or laterite of gneiss, at elevations from 1000 to over 2500 m.

CONSERVATION STATUS. — Humbertacalia pyrifolia has an extent of occurrence (EOO) of 90 776 km 2, an area of occupancy (AOO) of 76 km 2, and 15 locations with respect to the most plausible threat of fire. It occurs within the protected areas of Andohahela, Andringitra, Ankaratra-Manjakatompo, Corridor forestier Ambositra-Vondrozo, Ivohibe, Marojejy, Ranomafana, Tsaratanana. Being widespread and occurring in many protected areas, H. pyrifolia is assessed as “Least Concern” [LC] according to IUCN Red List Categories and Criteria ( IUCN 2012).

ADDITIONAL SPECIMENS EXAMINED. — Madagascar. Analamanga Region [Prov. Antananarivo]: Manjakandriana , [18°55’S, 47°49’E], IV.1906, fl. & im. fr., Alleizette 809 M ( P [ P02397487 ]) ; Angavokely , [18°55’S, 47°46’E], X.1960, fl., Bosser 14535 ( MO, TAN) ; gorges de la Mandraka , [18°54’S, 47°55’E], 1000-1400 m, 16.VIII.1924, m. fr., Humbert & Perrier de la Bâthie 2297 ( P [ P02397502 ]) ; Angavokely , [18°50’S, 47°42’E], 20.X.1960, 1700 m, fl. & im. fr., Leandri 3239 ( P [ P02397507 ]) . — Anosy Region [Prov. Toliara]: Massif de l’Andohahelo , [24°42’S, 46°44’E], 1200-1800 m, 18-26.X.1928, fl., Humbert 6100 ( P [ P02397499 ]) . — Amoron’i Mania Region [Prov. Fianarantsoa]: Ambositra , [20°31’S, 47°15’E], 16.XI.1938, fl., Decary 13562 ( P [ P02397491 ]) ; Ambohimitombo forest , [20°42’30”S, 47°25’30”E], 1350-1440 m, 26.XII.1894, Forsyth-Major 353 ( P [ P02397490 ]) . — Atsimo-Atsinanana Region [Prov. Fianarantsoa]: Haute vallée de la Rienana (bassin du Matitanana), [22°14’30”S, 47°07’30”E], 1000-1400 m, 18.XI.1924, fl., Humbert 3469 ( G, P [ P02397500 ]) . — Diana Region [Prov. Antsiranana]: Massif du Tsaratanana ( Réserve naturelle n° 4), [14°02’S, 48°58’E], 2600 m, XI-XII.1937, fl. & m. fr., Humbert 18394 ( P [ P02397498 ]) ; ibid. loco, 2300-2875 m, XI-XII.1937, fl., Humbert 18468 ( P [ P02397496 ]) ; ibid. loco, 14°08’47”S, 48°58’22”E, 2450 m, 16.X.2001, bud & fl., Lowry et al. 5375 ( G, K [ K000662061 ], MO, P [ P02397505 ], TAN) ; ibid. loco, 16.VII.1954, bud, Réserves Naturelles 6337 ( G, MO, P [ P04130326 ], TAN) . — Haute Matsiatra Region [Prov. Fianarantsoa]: Parc national de Ranomafana, parcelle 1 à l’est de Vohiparara, au nord de la Route nationale 25, 21°14’S, 47°23’E, 1100-1200 m, 8-18.X.1993, fl., Kotozafy 311 ( MO, P [ P00558048 ], TAN, US [ US01832485 ]) . — Ihorombe Region [Prov. Fianarantsoa]: Pic d’Ivohibe , [22°31’S, 46°57’E], 1500-2000 m, 05.XI.1924, fl., Humbert 3275 ( P [ P02397501 ], TAN) ; Sendrisoa, Ambalavao , [22°13’30”S, 46°55’00”E], 9.X.1951, fl. & im. fr., Réserves Naturelles 3484 ( P [ P02397504 , P02397506 ], TAN) . — Vakinankaratra Region [Prov. Antananarivo]: Manjakatompo , [19°22’S, 47°18’E], 25.X.1951, fl., Benoist 1269 ( P [ P02397485 ], TAN) ; ibid. loco, 28.X.1951, Benoist 1278 ( P [ P02397483 ]) ; ibid. loco, 23.X.1951, fl. & m. fr., Benoist 1293 ( P [ P02397494 ]) ; ibid. loco, IX.1959, fl., Bosser 13324 ( TAN) ; ibid. loco, IX.1962, bud & fl., Bosser 16566 ( P [ P02397493 , P02397495 ], TAN) ; ibid. loco, 19°22’S, 47°16’E, 1550-2602 m, 20.IX.1993, fl., Lewis & Razafimandimbison 603 ( K, MO [MO-5815954], P [ P00558037 ], TAN [ TAN000980 ], US [ US01832494 ]) ; Tsiafajavona , [19°21’S, 47°14’E], 2000 m, X.1921, fl. Perrier de la Bâthie 13935 ( P [ P02397503 ], TAN, US [ US01832486 ]) . — Sine loco: Baron 4967 ( P [ P02397484 ]) ; Campenon s.n. ( P [ P02397492 ]) .

DESCRIPTION

Leaves petiolate; leaf laminas 3.5-8 × 2.5-4 cm, lanceolate to elliptic, base obtuse to rounded or subcordate, apex acute to acuminate, margins subentire, remotely mucronate-denticulate or dentate, glabrous on both surfaces, venation pinnate (conspicuous on both surfaces, including tertiary veins), rather coriaceous; petioles up to 0.8 cm long. Synflorescences axillary and terminal, thyrsoid-paniculiform. Capitula sessile or subsessile; involucres rather cylindrical, glabrous except for some arachnoid trichomes near base; involucral bracts (3-)5, 2.1-3 × 0.7-1.1 mm; supplementary bracts 3-4, 0.7-1.6 mm long, ovate. Florets (3-)5, 2.8-3.9 mm long; corollas tubular, 5-lobed, whitish; anther bases caudate, a third as long as filament collar; style branches truncate with a crown of sweeping trichomes. Achenes c. 2 × 0.4 mm, rather cylindrical, c. 5-ribbed, glabrous, straw-coloured; pappus 2.6-3.9 mm long, whitish.

NOTES

This species is morphologically close to Humbertacalia neoalleizettei and H. amplexifolia , with which it shares the glabrous, rather coriaceous leaves and the involucres composed of five involucral bracts. From H. amplexifolia , it differs in having pedunculate leaves with obtuse to rounded or subcordate bases (vs subsessile leaves with amplexicaul to semi-amplexicaul bases in H. amplexifolia ). The differences against H. neoalleizettei are explained above under this latter species.

The lectotype and the isolectotype at P of Vernonia asclepiadea contain mixed material of Humbertacalia pyrifolia and Conyza cf. bakeri Humbert. The duplicates at G, however, are only composed of Humbertacalia pyrifolia . In the protologue of Vernonia asclepiadea, Drake del Castillo (1899) remarked “Capitules […] à dix ou quinze fleurs” [Capitula … with 10 or 15 florets], which notably differs from the capitula of Humbertacalia pyrifolia composed of c. five florets; such mismatch might be explained by a confusion of the author because of the mixed material.

Figures

FIG. 4. — Holotype of Mikania pyrifolia Bojer ex DC., Bojer s.n. in G-DC (G00323809; © Herbier, Conservatoire et Jardin botanique de Genève, reproduced with permission).