A revision of Homalium sect. Nisa (Salicaceae) endemic to Madagascar
Wassel, Anna C.
Applequist, Wendy L.
Candollea
2020
2020-03-24
75
1
1
23
3MCJH
Baker
Baker
[839,1139,417,442]
Magnoliopsida
Salicaceae
Homalium
Plantae
Malpighiales
5
6
Tracheophyta
species
confertum
Lectotypus(designated by SLEUMER, 1973: 298): MADAGASCAR:“ Central Madagascar”, s.d., fr., Baron 3185( K[ K000231489] image seen; isolecto-: BM, L[ L0010973] image seen, P[ P00418088]!). Syntypus: MADAGASCAR:“Central Madagascar”, s.d., fr., Baron 3256( K[ K000231490] image seen).
Treeto 22 mtall, 60 cmdbh; bark exfoliating in plaques; twigs gray to medium brown, glabrous, leafing internodes (1.2–)1.7–4(–5)mm diam.; stipules fused, sometimes persistent. Leaveselliptic to oblong-elliptic, narrowly or broadly elliptic, or obovate, (5–)6– 16 × (1.8–)3– 6.2(–7) cm; base convex to cuneate; apex cuspidate, obtuse, acute, or rounded (shortacuminate); margin serrate to dentate or slightly crenate, rarely nearly entire, glands in tooth apices elongated and relatively conspicuous; secondary veins 8–14(–16) per side, sometimes with similar intersecondary veins; both surfaces glabrous (aberrantly bearing patches of short trichomes, possibly pathogenic), or abaxial surface moderately glaucous, drying medium to dark brown on both surfaces (rarely light green); petiole 3–7(–10) mm, glabrous. Inflorescencesracemose, axillary (often paired), (2–)4–8.5(– 11) cm; rachis glabrous (sparsely shortpubescent or more densely so in irregular patches); bracts and bracteoles (1.5–) 2–4 mm, glabrous except margins of bracts usually ciliate; flowers borne singly. Flowers5–6-merous, white to green or yellow-green; sepals 3–7 mmin flower, 8–12.5 mmin fruit, oblanceolate to spatulate or narrowly oblanceolateoblong, adaxial surface usually glabrous (midrib sometimes sparsely short-pubescent), abaxial surface usually glabrous (sparsely short-pubescent at base); sepal glands yellow, glabrous; petals ovate, 2–4 mm, both surfaces densely (to moderately) pubescent especially on apical half; filaments glabrous (sparsely pubescent on the basal portion), 1.7–3.1 mm; anthers (0.45–) 0.5–0.6 mm; styles 1.5–2.5 mm.
Vernacular names and use.– “Hazombato” ( Razafindramora 1, Ser vice Forestier 1776, 25277); “Hazombatofotsy ” ( Razanatsima et al. 1136, Service Forestier 7362, 16801, 25277); “Lalondalitra” ( Service Forestier 15406); “Longotra-fotsy” ( Service Forestier 1249); “Marankoditra” ( Réserves Naturelles 6043, Service Forestier 25277); “Tsianihiposa” ( Service Forestier 10148).
Wood is used to make unspecified products ( Service Forestier 25277).
Distribution, ecology and conservation status. – Homalium confertumis widespread in eastern and central regions of Madagascar. It usually occurs in humid forests at mid- to high elevations (range 445–1860 m), but also extends into relatively dry western forests (Ankarafantsika). Reported substrates include gneiss. It is sometimes common and locally dominant ( Randrianaivo et al. 526). It has been collected in several protected areas, including Ambohitantely, Anjanaharibe-Sud, Ankarafantsika, Montagne d’Ambre, and Zahamena. Its conservation status is estimated as “Least Concern” [LC].
Notes. – Homalium confertumwas lumped into H. nudiflorumby SLEUMER (1973). It differs from H. nudiflorum s.s.in its larger, often strongly toothed leaves with many marginal glands and its more densely pubescent petals; the final perianth size may also be larger. The two overlap in range, but H. confertumis more tolerant of dry climate and high altitude, with much of its habitat on the central plateau. It is similar to H. pachycladumand H. retusum, which also overlap in range, in maximum leaf size, but H. pachycladumand retusumare distinguished by entire leaf margins, fewer leaf glands, and petals glabrous on the abaxial surface. Several possible hybrids between H. confertumand H. nudiflorumare seen in two regions where both are known, and gene flow is suspected to be responsible for some of the range of variation in H. nudiflorum; these are discussed under the latter species. Hybridization is seen in most sections of Homalium, even rarely among species of different sections ( APPLEQUIST, 2018b), so the ability of these species to hybridize does not suggest that they should not be recognized as distinct, given their significant morphological and ecological differences.
Additional material examined.– MADAGASCAR. Reg. Alaotra-Mangoro[Prov. Toamasina]: PN Zahamena, 17°38'25"S 48°38'34"E, 989 m, 30.III.2000, buds, Ratovosonet al. 184( MO, P); Manaka, Ambatondrazaka, 20.II[?].1953, fl., Reserves Naturelles6043( MO); P. K. 39 route d’Anosibe, canton and souspréfecture Anosibe, 4.V.1965, fr., Service Forestier25277( P). Reg. Amoron’i Mania[Prov. Fianarantsoa]: commune d’Ambalamanakana, 20°44'01"S 47°11'42"E, 1860 m, 27.III.1996, fl., Rakotomalazaet al. 681A( MO, P). Reg. Analamanga[Prov. Antananarivo]: Tampoketsa-Ankazobe, RS Ambohitantely, 18°11'52.5"S 47°17'3"E, 1620 m, 7.III.2004, fl., Almeda et al.8636( MO); Anjozorobe, commune d’Ambongamarina, Andreba, 18°16'55"S 47°54'24"E, 1400 m, 11.III.2000, fl., Randrianaivoet al. 526( MO); Ambohitantely RS, 18°11'46"S 47°17'24"E, 1620 m, 12.III.1997, Ravololonanaharyet al. 69( MO). Reg. Analanjirofo[Prov. Toamasina]: Beanana, 700 m, 22.II.1954, fl., Service Forestier9058( MO, P[2 sheets]). Reg. Anosy[Prov. Toliara]: Antsotso Avaratra, forêt Tsitongambarika, 24°34'S 47°12'E, 2.IV.2008, fr., Razakamalalaet al. 4148( MO, P). Reg. Atsinanana[Prov. Toamasina]: Ambodilendemy, Ankerana, 18°25'49"S 48°47'14"E, 890 m, 24.III.2011, fl., Antilahimena7778( MO); Ambodilendemy, vers le sommet d’Ankerana, 18°25'49"S 48°47'14"E, 900m, 14.III.2011, fl., Ravelonarivo& Felix3663( MO); Vatomandry, Ambalabe, 19°09'27"S 48°34'57"E, 596 m, 11.III.2013, fl., Razanatsimaet al. 1136( BR, G, K, MO, USMS). Reg. Boeny[Prov. Mahajanga]: Réserve Naturelle Intégrale d’Ankarafantsika, 16°18'00"S 46°49'00"E, 22.IV.1994, fl., Rajemisa24( MO). Reg. Bongolava[Prov. Antananarivo]: Tsiroanomandidy, Ambaravaranala, 18°25'S 45°40'E, 1190–1200 m, 25.VI.1997, fl., Rakotomalazaet al. 1353( G, MO). Reg.DIANA [Prov. Antsiranana]: Montagne d’Ambre(partie N.O.), 1000–1800 m, 23.XII.1967, fr., Bernardi12003( MO, P); contreforts occidentaux du Massif de Marojejy( NE) près du col de Doanyanala (limite des bassins de la Lokoho et de l’Andraronga), 800–1200 m, 25.I–25. II.1949, fl., Humbert23040( P[3 sheets]); montagnes au N de Mangindrano(haute Maevarano) jusqu’aux sommets d’Ambohimirahavavy(partage des eaux Mahavavy-Androranga), 1500 m, 19.I–12.II.1951, fr., Humbert& Capuron24888( P); flanc S du M. Tsaratanana, 1700 m, XII.1912, fl., Perrier de la Bâthie6705( P). Reg. Haute Matsiatra[Prov. Fianarantsoa]: Ampamaherana, Fianarantsoa, 13.XII.1949, fl., Service Forestier1249( P). Reg.SAVA [Prov. Antsiranana]: Daraina, forêt d’Antsahabe, 13°13'03"S 49°32'46"E, 780 m, 2.XII.2004, fr., Gautier4806( MO, P); Ampasindava, forêt de Bongomihirahavavy, 13°46'11"S 48°04'58"E, 445 m, 4.XII.2013, fr., Gautieret al. 6092( G, P); massif de l’Anjanaharibe(pentes et sommet N) a l’W d’Andapa(haute Andramonta, bassin de la Lokoho: NE), 1600–1800 m, 10.XII.1950– 3.I.1951, fl., Humbertet al. 24704( P); Doany, Anjialavahely, 14°17'41"S 49°32'50"E, 949 m, 15.III.2006, fl., Rakotovaoet al. 2986( MO, P); Anjialavabe, Ankiakabe, 14°10'47"S 49°22'01"E, 1567 m, 23.II.2007, fl., Ravelonarivoet al. 2238( MO, P); Antalaha, Bealampona, village de Befingotra, 14°45'11"S 049°28'49"E, 762 m, 21.IV.1997, fl., Razafindramora1( MO). Reg. Sofia[Prov. Mahajanga]: Marsoandakana, 14°55'39"S 49°25'52"E, 1176 m, 23.II.2008, fl., Bernardet al. 876( MO); NW du campement Bemafo, 14°13'17"S 49°03'55"E, 1830 m, 26.X.2005, fl., Buerkiet al. 106( MO, P). Reg. Vakinankaratra[Prov. Antananarivo]: Angodona, Tsinjoarivo, 6.VI.1950, fl., Service Forestier1766( P[2 sheets]). Reg. Vatovavy-Fitovinany[Prov. Fianarantsoa]: Ampasinambo, Nosy-Varika, 21.IV.1954, fl., fr., Service Forestier10148( MO, P).
3698440398
K, BM, L, P
Madagascar
Central Madagascar
5
6
K000231489, L0010973, P00418088
1
lectotype
3698440382
K
Madagascar
MADAGASCAR
5
6
K000231490
1
syntype
3698440323
2000-03-30
MO, P
PN Zahamena & Ratovoson
Madagascar
989
-17.640278
Reg. Alaotra-Mangoro
21
48.64278
7
8
1
Toamasina
3698440350
20. II [?]. 1953
MO
Reserves Naturelles
Madagascar
Ambatondrazaka
Manaka
7
8
1
3698440411
1965-05-04
P, K
Service Forestier
Madagascar
canton and sousprefecture Anosibe
7
8
1
3698440480
1996-03-27
MO, P
Rakotomalaza
Madagascar
1860
-20.733612
commune d'Ambalamanakana
21
47.195
Reg. Amoron'i Mania
7
8
1
Fianarantsoa
3698440467
2004-03-07
MO
Almeda et al.
Madagascar
1620
-18.197916
Tampoketsa-Ankazobe
14
47.284164
Reg. Analamanga
7
8
1
Antananarivo
3698440442
2000-03-11
MO
Randrianaivo
Madagascar
Anjozorobe
1400
-18.281944
Andreba
21
47.90667
d'Ambongamarina
7
8
1
3698440424
1997-03-12
MO
Ravololonanahary
Madagascar
1620
-18.19611
Ambohitantely RS
21
47.29
7
8
1
3698440469
1954-02-22
MO, P
Service Forestier
Madagascar
700
Beanana
Reg. Analanjirofo
7
8
1
Toamasina
3698440380
2008-04-02
MO, P
Razakamalala
Madagascar
-24.566668
Antsotso Avaratra
1250
47.2
Reg. Anosy
7
8
1
Toliara
3698440482
2011-03-24
MO
Antilahimena
Madagascar
Reg. Atsinanana
890
-18.430277
Ankerana
21
48.78722
Ambodilendemy
7
8
1
Toamasina
3698440329
2011-03-14
MO
Ravelonarivo & Felix
Madagascar
900
-18.430277
vers le sommet d'Ankerana
21
48.78722
Ambodilendemy
7
8
1
3698440444
2013-03-11
BR, G, K, MO, USMS
Razanatsima
Madagascar
596
-19.1575
Ambalabe
21
48.5825
Vatomandry
7
8
1
3698440315
1994-04-22
MO
Rajemisa
Madagascar
-16.3
Reserve Naturelle Integrale d'Ankarafantsika
21
46.816666
Reg. Boeny
7
8
1
Mahajanga
3698440431
1997-06-25
1949-02-25
1949-01-25
G, MO
Rakotomalaza
Madagascar
Reg.
1195
-18.416666
Tsiroanomandidy
1275
45.666668
Reg. Bongolava
7
8
1
Antananarivo
3698440333
1967-12-23
1949-02-25
1949-01-25
MO, P
Montagne d'Ambre & Bernardi
Madagascar
Reg.
1400
-18.416666
Reg.
1275
45.666668
Reg. Bongolava
7
8
1
Antsiranana
3698440347
1949-01-25
1949-02-25
1949-01-25
NE, P
Humbert
Madagascar
Reg.
1000
-18.416666
contreforts occidentaux du Massif de Marojejy
1275
45.666668
Reg. Bongolava
7
8
1
Antananarivo
3698440354
1951-01-19
1951-02-12
1951-01-19
P
Humbert & Capuron
Madagascar
Reg.
1500
-18.416666
jusqu'aux sommets d'Ambohimirahavavy
1275
45.666668
Maevarano
7
8
1
Antananarivo
3698440340
1912-12
1949-12-13
1912-12
P
Service Forestier
Madagascar
Reg.
1700
-18.416666
Reg. Haute Matsiatra
1275
45.666668
Reg. Bongolava
7
8
1
Fianarantsoa
3698440474
2004-12-02
1949-02-25
1949-01-25
MO, P
Gautier
Madagascar
Reg.
780
-18.416666
foret d'Antsahabe
1275
45.666668
Daraina
7
8
1
Antsiranana
3698440438
2013-12-04
1949-02-25
1949-01-25
G, P
Gautier
Madagascar
Reg.
445
-18.416666
Ampasindava
1275
45.666668
Reg. Bongolava
7
8
1
Antananarivo
3698440407
1950-12-10
1951-01-03
1950-12-10
P
Humbert
Madagascar
Reg.
1700
-18.416666
massif de l'Anjanaharibe
1275
45.666668
Reg. Bongolava
7
8
1
Antananarivo
3698440473
2006-03-15
1949-02-25
1949-01-25
MO, P
Rakotovao
Madagascar
Reg.
949
-18.416666
Anjialavahely
1275
45.666668
Doany
7
8
1
Antananarivo
3698440339
2007-02-23
1949-02-25
1949-01-25
MO, P
Ravelonarivo
Madagascar
Reg.
1567
-18.416666
Ankiakabe
1275
45.666668
Anjialavabe
7
8
1
Antananarivo
3698440400
1997-04-21
1949-02-25
1949-01-25
MO
Razafindramora
Madagascar
Reg.
762
-18.416666
Bealampona
1275
45.666668
Antalaha
7
8
1
Antananarivo
3698440440
2008-02-23
1949-02-25
1949-01-25
MO
Bernard
Madagascar
Reg.
1176
-18.416666
Marsoandakana
1275
45.666668
Reg. Sofia
7
8
1
Mahajanga
3698440370
2005-10-26
1949-02-25
1949-01-25
MO, P
Buerki
Madagascar
Reg.
1830
-18.416666
Tsiroanomandidy
1275
45.666668
Reg. Bongolava
7
8
1
Antananarivo
3698440413
1950-06-06
1949-02-25
1949-01-25
P
Service Forestier
Madagascar
Reg.
1195
-18.416666
Reg. Vakinankaratra
1275
45.666668
Reg. Bongolava
7
8
1
Antananarivo
3698440365
1954-04-21
1949-02-25
1949-01-25
MO, P
Service Forestier
Madagascar
Reg.
1195
-18.416666
Ampasinambo
1275
45.666668
Reg. Vatovavy-Fitovinany
7
8
1
Fianarantsoa