Homalium densispicatum Appleq.

Applequist, Wendy L., 2018, A revision of Homalium sect. Odontolobus (Salicaceae) endemic to Madagascar, Candollea 73 (1), pp. 27-48: 31-34

publication ID

http://doi.org/ 10.15553/c2018v731a4

persistent identifier

http://treatment.plazi.org/id/03CAA927-3A1C-FFBA-E74E-F9A5FCE52E33

treatment provided by

Carolina

scientific name

Homalium densispicatum Appleq.
status

 

2. Homalium densispicatum Appleq.   , spec. nova ( Fig. 1).

Holotypus: MADAGASCAR. Prov   . Toliara: Anosy , Fort Dauphin , Iabokoho , Antsotso, forêt d’Ivohibe, 24°34’14’’S 47°12’10’’E, 230 m, 2.IV.2008, fl., Rabenantoandro et al. 1884 (MO-6474628!; iso-: P [ P06171672]!, TAN) GoogleMaps   .

Homalium densispicatum differs   from H. moniliforme H. Perrier   in having larger leaves, (5.5-)7-15(-17) × (1.5-)2.1-6(-6.9) cm (vs (1.8-)2.7-6.8 × 0.7-2.6(-3) cm); inflorescences canescent (vs minutely pubescent or glabrous); and flowers borne in elongated many-flowered glomerules along most of the rachis (vs in well-separated, moniliform glomerules).

1 cm

Tree to 12 m tall; young twigs glabrous. Leaves: petiole 2.5-20(-30) mm long, glabrous; blade narrowly elliptical to elliptical (oblanceolate to oblong-oblanceolate, obovate), (5.5-)7-15(-17) × (1.5-)2.1-6(-6.9) cm; base cuneate to attenuate or convex, usually attenuate at extreme base; margins crenate-serrulate (subentire, crenate-serrate or crenulate), often slightly revolute; apex rounded to acute or cuspidate (shallowly emarginate, short-acuminate). Inflorescences spicate with a thick rachis, 1.4-7 cm long, canescent; flowers in elongated manyflowered clusters, sessile; bracts transversely (to very broadly) oblong, deltoid or ovate, often irregular; bracteoles reduced to minute teeth, caducous. Flowers (6-)7(-8)-merous, white or greenish; sepals ovate to oblong or broadly ovate-deltoid, 0.2-0.3(-0.4) mm long; petals broadly (transversely) oblongelliptical to oblong-ovate, (0.4-) 0.5-0.8 mm long, glabrous (pubescent abaxially but not ciliate), apex rounded; filaments 0.1-0.4(-0.5) mm long; upper surface of ovary densely shorttomentose; styles (2-)3, 0.1-0.4 mm long.

Distribution, ecology and conservation status. – Homalium densispicatum   is primarily native to humid forests in southeastern Madagascar at low (seldom to moderate) elevations. As herein circumscribed, it includes one disjunct population from northern Madagascar. Only eight distinct locations are known for H. densispicatum   (if the Antsiranana collection is included). Most low-elevation forest in Madagascar is now badly fragmented. However, most collections are from two protected areas (Manombo, Tsitongambarika) where the species seems not to be rare and further decline in habitat extent or quality may be avoidable. Therefore it is suggested that an appropriate preliminary assessment of conservation status would be “Least Concern” [LC].

Notes. – Homalium densispicatum   shares extremely reduced, tightly clustered flowers with H. moniliforme   , and some specimens have previously been assigned to that species. However, the leaves are much larger, with numerous veins and sometimes much longer petioles, the inflorescences are much more densely pubescent, and the flowers are borne on a thick rachis in elongated many-flowered clusters that at their termini are mostly close to one another on alternating sides of the rachis, giving the inflorescence a uniformly thick, rather than moniliform appearance.

The distribution is primarily southeastern. One smallleaved collection (Razakamalala et al. 55) is known from Antsiranana, far to the north; though this distribution is suspicious, the specimen is overall morphologically consistent with H. densispicatum   and not with H. moniliforme   , e.g., in having thick inflorescences with elongated, nearly contiguous glomerules. A second northern collection, Service Forestier 28807 from Ile Sainte-Marie (partie S de la forêt de Kalalao, 16.V.1969, fr., P [2 sheets]), has leaves to 9.7 × 4.1 cm, yet in other features it seems to resemble H. moniliforme   more than H. densispicatum   ; it is therefore treated as incertae sedis. Specimens from Fianarantsoa province have smaller leaves than those from Toliara; one of the latter, Razafimandimbison et al. 223, has unusually narrow and strongly toothed leaves and might represent a distinctive local variant.

Paratypi. – MADAGASCAR. Prov. Antsiranana: Fiv. Antalaha, Fkt. Sahafary   , 15°17’34’’S 50°22’07’’E, 173 m, 18.II.2001, fl., Razakamalala et al. 55 ( MO). Prov. Fianarantsoa: Ranomafana GoogleMaps   , XII.1963, fl., Chabonis s.n. ( P); Fkt. Manombo, Réserve Spéciale de Manombo   , 23°01’19’’S 47°43’56’’E, 30 m, 14.XI.2001, fr., Rabenantoandro et al. 780 ( MO); forêt de Manombo, à 30 km au S de Farafangana , J. B GoogleMaps   . 16, 26.VI.1954   , fl. & fr., Service Forestier 9205 (MO, P [7 sheets]); Ihorombe, Manombo , 21.VII.1955, fr., Service Forestier 15240 ( P). Prov. Toliara: Fkt. Antsotso, Ivohibe forest   , 24°34’10’’S 47°12’37’’E, 41 m, 24. V GoogleMaps   .2006, fl., Antilahimena et al. 4846 ( P); Fkt. Iaboakoho, forêt d’Ampasina   , 24°34’30’’S 47°08’35’’E, 119 m, 25. I GoogleMaps   .2015, fl., Randrianarivony et al. 623 ( MO); village d’Antsotso , forêt de Bemangily   , 24°35’33’’S 47°12’52’’E, 22. V GoogleMaps   .2006, fl., Randriatafika et al. 672 ( MO, P); forêt de Manantantely à 15 km au NW de Fort-Dauphin   , 24°59’S 46°55’E, 50-100 m, 24. VI GoogleMaps   .1996, fl., Razafimandimbison 223 ( BR, G, K, MO, P [2 sheets]); Antsotso Avaratra, forêt Tsitongambarika   , 24°34’16’’S 47°12’05’’E, 271 m, 1.IV.2008, fl., Razakamalala et al. 4113 ( MO, P). Sine loco: s.d., fl., Service Forestier 71-R-176 ( P) GoogleMaps   .

3. Homalium longistaminum H. Perrier   in Mém. Mus. Natl. Hist. Nat. 13: 287. 1940.

Lectotypus (designated here): MADAGASCAR. Prov. Toliara: vallée de la Manambolo, rive droite (bassin du Mandrare) aux env. d’Isomono (confluent de la Sakamalio), 400-900 m, XII.1933, buds & fl., Humbert 12914 ( P [ P04679979]!; isolecto-: L [ L0010953] image seen, P [ P04679980]!)   .

Tree to 12 m tall, 30 cm dbh; young twigs glabrous or minutely pubescent. Leaves: petiole 4-11 mm long, glabrous (sparsely, minutely pubescent); blade irregularly elliptical to broadly elliptical or ovate (lanceolate), (3.2-)3.5-7.5 × 1.6-3.3(- 4.8) cm; base convex to rounded (attenuate at extreme base); margins irregularly crenate apically to crenate-serrate for most of their length; apex acute to obtuse or rounded (short-acuminate). Inflorescences racemose, (2.2-) 4-6.5 cm long, canescent or in part moderately pubescent; flowers often borne in clusters of 2 or 3, on pedicels 0.3-1.4 mm long; bracts transversely to broadly deltoid; bracteoles very thick, to subterete at base, densely pubescent (absent or rapidly caducous). Flowers 6- or 7-merous, pale or yellowish green; sepals deltoid to ovate, (0.3-)0.4-0.5(-0.6) mm long; petals oblong to somewhat obovate, 0.8-1.2 mm long, margins short-ciliate and both surfaces pubescent, densely so abaxially and usually at base adaxially, apex rounded or obtuse; filaments 1.1-1.7 mm long; upper surface of ovary canescent; styles (3-)4(-5), 1.1-1.7 mm long.

Vernacular names. – “Tsimalagnilamba” (Eboroke 980);

“Tsimalamba” (Humbert 12914).

Distribution, ecology and conservation status. – Homalium longistaminum   is confined to a limited area in southeastern Madagascar, where it occurs mostly in low-elevation humid forests. The fact that very few collections are available, although both Andohahela and Ranopiso are relatively well-collected, suggests that the species is rare in its native range. Four collections are known, pertaining to only three distinct localities, and giving an AOO of no more than 12 km 2. Two of these three are in the area of Andohahela RNI, hence protected. However, the species should be considered “Vulnerable” [VU B1ab(iii)+B2ab(iii)] based on its small AOO (<20 km 2) and number of locations (≤ 5).

Note. – In publishing this species, PERRIER DE LA BÂTHIE (1940) did not note that there were two sheets of the type collection at P; Sleumer incorrectly marked both as “ holotype ”. The sheet numbered P04679980 has a determination label by Perrier, while the sheet numbered P04679979 has notations on the label in the same handwriting that read “ Homalium (Blackwellia) longistaminum H. Perr.   ”, with the addition of “n. sp.”, and “Type” (double underlined). The latter sheet is in better condition, having a fragment packet that contains partially open flowers; it would certainly be a more suitable type and Perrier de la Bâthie probably intended it as such. However, since both sheets were used by Perrier de la Bâthie and no distinction between them was made in the protologue, they are regarded as syntypes   and it is therefore necessary to designate a lectotype.

Additional material examined. – MADAGASCAR. Prov. Toliara: RNI d’Andohahela , parcelle n° 2, 24°49’49’’S 46°32’15’’E, 30-50 m, 16.III.1994, Andrianarisata et al. 101 ( MO [2 sheets]) GoogleMaps   ; Ranopiso, Evasia , 24°46’S 46°41’E, 350 m, s.d., post-fl., Eboroke 980 ( G, MO) GoogleMaps   ; Andohahela, parcelle n° 2, Ihazofotsy , 24°50’S 46°33’E, 50-200 m, 2-5.III.1993, fr., Randriamampionona 152 ( MO, P) GoogleMaps   .

4. Homalium lucidum Scott-Elliot   in J. Linn. Soc., Bot. 29: 24. 1891.

Lectotypus (designated by SLEUMER, 1973: 307): MADA- GASCAR. Prov. Toliara: Fort Dauphin , V.1889   , fl., Scott Elliot 2661 ( K [ K000231842] image seen; isolecto-: P [ P04704037]!)   .

Tree to 30 m tall, 60 cm dbh; bark dark gray-brown, sometimes slightly fissured or peeling, with a bright yellow slash; young twigs glabrous. Leaves: petiole 3-10(-19) mm long, glabrous (glaucous, peeling); blade elliptical to lanceolate (narrowly lanceolate, aberrantly broadly elliptical), 3.5-11.5 × 1.5-3.8(-4.3) cm; base convex; margins serrulate to crenateserrulate (shallowly crenate, subentire); apex acute to acuminate (emarginate, rounded-cuspidate). Inflorescences racemose, (2.5-)4-10(-12) cm long, glabrous; flowers proximally often in clusters of 2 or 3, sessile (pedicellate with pedicels to 2 mm long); bracts ovate to broadly ovate; bracteoles ovate, minute, caducous. Flowers 6-7(-8)-merous, pale green to white, cream or yellowish, or brown with age (once described as red); sepals deltoid, 0.3-0.4(-0.5) mm long; petals lanceolate (narrowly ovate) to oblong-lanceolate or narrowly elliptical (elliptical), 1.5-2.5(-3.1) mm long, ciliolate, otherwise glabrous (or adaxial surface sparsely short-pubescent), apex acute; filaments 0.3-0.7 mm long; upper surface of ovary sparsely to moderately short-pubescent; styles 2-3, 0.3-0.5 mm long.

Vernacular names. – “Fotsakara (g[rands] f[euilles])” (Service Forestier 2718, 2737); “Hazofotsy” (Antilahimena et al. 4835); “Hazokoaky” (Service Forestier 13942); “Mafaikoditra” (Antilahimena et al. 1139); “Maroampotolia” (Réserves Naturelles 3668); “Menavahatra” (Antilahimena et al. 7110); “Ramisaona” (Service Forestier 14569, 14608).

Distribution, ecology and conservation status. – Homalium lucidum   is widely distributed in humid regions of Madagascar and occurs from near sea level to over 1400 m elevation. The species is widely distributed from Antananarivo province in the center to Toliara province in the south and is relatively common with many localities within the protected area network (i.e., Andohahela, Anjozorobe, Betampona, Makira, Nosy Mangabé and Tsitongambarika). Homalium lucidum   is therefore assigned a preliminary assessment of conservation status of “Least Concern” [LC].

Note. – Homalium lucidum   was described from only one collection. As for other species published by Scott Elliot, the duplicate at K, where he worked, has been informally considered to be the “ holotype.” However, as other duplicates of his own collections were certainly available to him, and the publication did not specify that specimens cited were held at K, the two known duplicates of Scott Elliot 2661 should be regarded as syntypes under Art. 9.5 of the ICN ( MCNEILL et al., 2012). SLEUMER’S (1973) subsequent statement that the K and P duplicates were the “ holotype ” and “isotype”, respectively, was an effective selection of the former as lectotype, with the use of “ holotype ” being a correctable error under Art. 9.9.

Selected material examined. – MADAGASCAR. Prov. Antananarivo: 3.0 km NW of Ambohitsaratelo-Bebao ( NW of Tsiroanomandidy )   , 1100-1200 m, 16. I   .1985, fl., Dorr et al. 3587 ( MO, P); Bongolava   , 1300 m, VII.1974, fl. & fr., Morat 4639 ( MO [2 sheets], P [4 sheets]); Fkt. Ambaravaranala , 18°25’S 45°40’E GoogleMaps   , 1190-1200 m, 25. VI   .1997, fr., Rakotomalaza et al. 1344 ( G, K, MO); forêt de Besofina à 8 km au S de Betatao , 18°15’10’’S 47°53’27’’E GoogleMaps   , 1386 m, 9.III.2000, fl., Randrianaivo et al. 517 ( MO, P); 7 km E of Anjozorobe , 18°22’S 48°00’E GoogleMaps   , 1300 m, 11. V   .1987, fl., Schatz et al. 1380 ( MO, P). Prov. Fianarantsoa: Fkt. Iabomaro , 23°11’07’’S 47°42’32’’E GoogleMaps   , 24 m, 19. VI   .2004, fr., A. Randrianasolo et al. 878 ( P); Vangaindrano   , 20.I.1950   , fl., Service Forestier 2737 (P); Manakara, Vakoary , 11.V.1955   , fr., Service Forestier 14569 (P); Manakara, forêt Belambo , 11.V.1955   , Service Forestier 14608 (P). Prov. Mahajanga: 9.6 km NW of Ambohistaratelo-Bebao, 1200 m, 14. I   .1985, fl., Dorr et al. 3535 ( MO, P); 5 km à l’E de Bandabe, 15°31’08’’S 49°06’00’’E, 3696 GoogleMaps   ’, 25.IV.2007, fr., Ravelonarivo et al. 2253 ( MO, P). Prov. Toamasina: 5 km du village d’Anony, vers Ankarefobe , 17°12’26’’S 48°33’13’’E GoogleMaps   , 1164 m, 22.IV.2005, fl., Andriamijaharivo et al. 577 ( MO); Fkt. Andranofotsy , 15°25’14’’S 49°48’51’’E GoogleMaps   , 140 m, 14.VII.2002, fr., Antilahimena et al. 1139 ( MO, P); Fkt. Ampitambe, Ambatovy, Andranovery , 18°52’43’’S 48°17’38’’ W GoogleMaps   , 1010 m, 10. VI   .2009, fl., Antilahimena et al. 7110 ( G, K, MO, P); Andapanomby, près de la rivière Ampandisanana , Makira NW, 15°21’48’’S 49°07’06’’E GoogleMaps   , 25.IV.2007, fr., Bernard & Birkinshaw 462 ( G, MO, P); Nosy Mangabé , 15°30’S 49°45’E GoogleMaps   , 17.IV.1988, fl. & fr., Leeuwenberg 13933 ( MO, P); confluence de l’Onive et du Mangoro   , 600 m, IX.1926 [?], fl., Perrier de la Bâthie 17012 ( P); entre Moango et Antanamarina , 17°33’57’’S 48°53’58’’E GoogleMaps   , 740 m, 27.X.2000, fr., Randrianjanaka et al. 586 ( MO, P); entre Manakambahiny Est et Nonokambo , 17°45’34’’S 48°42’04’’E GoogleMaps   , 7.III.2001, fl. & fr., Randrianjanaka et al. 606 ( MO, P); RN I   [Betampona], 20.III.1952, fl., Réserves Naturelles 3668 ( MO, P [2 sheets]); Nosy Mangabe , 15°30’S 49°46’E GoogleMaps   , 0-330 m, 13-23. IV.1988, fl., Schatz & Gentry 2055 ( MO, P); Bassin de la Manonga (effluent [rive gauche] de la Rantabe), env. de Sahajinja   , 700 m, 5.III.1954, fl., Service Forestier 9107 ( P). Prov. Toliara: Fkt. Antsotso, Ivohibe forest , 24°34’10’’S 47°12’37’’E GoogleMaps   , 41 m, 24. V   .2006, fr., Antilahimena et al. 4835 ( P); Andohahela [NP], parcelle 1, Eminiminy , 24°40’S 46°48’E GoogleMaps   , 200-700 m, 4-24. V   .1993, fr., Randriamampionona 309 ( MO, P); ibid. loco   , 4-24.V.1993   , fl., Randriamampionona 376 (MO, P); Imonty , 3.VIII.1955, fr., Service Forestier 13942 ( P)   .

P

Museum National d' Histoire Naturelle, Paris (MNHN) - Vascular Plants

TAN

Parc de Tsimbazaza

MO

Missouri Botanical Garden

S

Department of Botany, Swedish Museum of Natural History

J

University of the Witwatersrand

B

Botanischer Garten und Botanisches Museum Berlin-Dahlem, Zentraleinrichtung der Freien Universitaet

V

Royal British Columbia Museum - Herbarium

I

&quot;Alexandru Ioan Cuza&quot; University

VI

Mykotektet, National Veterinary Institute

BR

Embrapa Agrobiology Diazothrophic Microbial Culture Collection

G

Conservatoire et Jardin botaniques de la Ville de Genève

K

Royal Botanic Gardens

L

Nationaal Herbarium Nederland, Leiden University branch

E

Royal Botanic Garden Edinburgh

Kingdom

Plantae

Phylum

Tracheophyta

Class

Magnoliopsida

Order

Malpighiales

Family

Salicaceae

Genus

Homalium

Loc

Homalium densispicatum Appleq.

Applequist, Wendy L. 2018
2018
Loc

Homalium longistaminum

H. Perrier 1940: 287
1940
Loc

Homalium lucidum

Scott-Elliot 1891: 24
1891