New species and species reports of Croton L. (Euphorbiaceae) from the eastern forest corridor of Madagascar Author Kainulainen, Kent Herbarium, Department of Ecology and Evolutionary Biology, 3600 Varsity Drive, Ann Arbor, Michigan 48108, U. S. A. Author Ee, Benjamin van Department of Biology, Universidad de Puerto Rico, Recinto Universitario de Mayagüez, Mayagüez, PR 00680, Puerto Rico, U. S. A. Author Antilahimena, Patrice Missouri Botanical Garden, B. P. 3391, Antananarivo 101, Madagascar. Author Razafindraibe, Hanta Parc Botanique et Zoologique de Tsimbazaza, rue Kasanga Fernand, Antananarivo 101, Madagascar. Author Berry, Paul E. Herbarium, Department of Ecology and Evolutionary Biology, 3600 Varsity Drive, Ann Arbor, Michigan 48108, U. S. A. peberry@umich.edu text Candollea 2016 2016-11-23 71 2 327 356 journal article 2894 10.15553/c2016v712a17 3ba10b86-da39-40e8-898c-ee3dfa6f0f05 2235-3658 5721805 Croton lasiopyrus Baill. in Bull. Mens. Soc. Linn. Paris 2: 926. 1890 ( Fig. 1C , 14 ). Lectotypus (designated here): MADAGASCAR : “Central Madagascar” , X.1882 , Baron 1951 ( P [ P00133406 ]!; isolecto- : K [ K001040378 ]!, P [ P00133407 ]!). Syntypi : MADAGASCAR : “Central Madagascar” , X.1882 , Baron 2114 ( K [ K001040377 ]!, P [ P00133408 ]!); “Central Madagascar” , s.d., Baron 4078 ( K [ K001040376 ]!); Fort Dauphin , s.d., Scott-Elliot 1557 ( P [ P00133052 packet in upper right]!) . Shrubs 1-4 m tall. Branches with fuzzy reddish-brown indument. Young shoots, petioles, and inflorescence axes hirsute, with densely ferrugineous-fasciculate trichomes, with copious red sap emerging when young stems are cut. Bark on older stems conspicuously longitudinally striate with whitish fissures on smooth grayish brown background, branching di- or trichotomous. Stipules minute, often hidden by pubescence. Leaves alternate to mostly opposite or ternate, the emerging ones usually whitish from the dense indument and anisophyllous (one of the pair or trio much smaller than the others). Petioles 0.8-2.0 cm long, with two subsessile to shortly stipitate discoid glands c. 1 mm diam. at the apex or just beneath the leaf blade. Leaf blades (broadly) elliptic to obovate, 4-15 × 2.5-8 cm , apex rounded to acutely acuminate, rounded to truncate at base, margin entire or somewhat serrate in distal half, firmly chartaceous, upper surface stellate-pubescent (densely so when young but becoming glabrescent with age except for pubescent midvein), softly and densely pubescent on lower surface, dark green above, only slightly paler on lower surface, brochidodromous, with 5-7 pairs of secondary veins. Inflorescences shortly racemose, terminal or axillary, epedunculate, 1.0- 3.5 cm long, few-flowered, bisexual or all staminate, when bisexual with shortly-pedicellate pistillate flowers close to the node, the pedicel 2-3 mm long, the staminate flowers with divergent pedicels 2-6 mm long. Staminate flowers with densely stellate-hirsute, globose buds; sepals 5, lanceolate, 3.0 × 1.5 mm , abaxially stellate-pubescent; petals 5, oblong, obtuse, 2 × 1 mm , sericeous on both surfaces and margins, white; glands 5, discoid, c. 0.5 mm diam.; stamens c. 15, filaments 1-2 mm long, basally pilose, anthers 0.6-0.8 mm long; receptacle villous. Pistillate flowers : sepals 5, lanceolate, 6.0-7.0 × 1.5-2 mm , abaxially densely stellate; petals lacking or subulate and c. 1 mm long; ovary globose, c. 5 mm diam., densely stellatehirsute; styles short, stellate-lepidote (branching pattern not discernible with available material). Capsules depressed globose, densely ferrugineous-hirsute, c. 10 × 8 mm ; columella 7-8 mm long, cornute and fimbriate at apex. Seeds oblong-ellipsoid, c. 6.5 × 3.5 mm , smooth, dark brown; caruncle c. 0.5 × 0.5 mm . Etymology. – The specific epithet alludes to the woolly fruit of this species. Fig. 11. – Croton radiatus P.E. Berry & Kainul. A. Holotype specimen of Croton radiatus at MICH; B. Inflorescence with a pair of basal pistillate flowers and five distal staminate flower buds; C. Underside of a leaf showing both whitish stellate-lepidote trichomes and brown fasciculate to multiradiate trichomes; D. Leaf base with a pair of stipitate, discoid glands emerging from the lamina; E. Staminate flower (7 anthers missing); F. Staminate flower with stamens removed to show the nectaries; G. Pistillate flower; H. Top view with the ovary removed to show the five nectaries and glandular filaments. [ E-F: Cours 1257; G-H: Razanatsoa & Marcellin 279 ] Fig. 12. – Croton plurispicatus P.E. Berry, Kainul. & B.W. van Ee ( A-F ) and C. hypochalibaeus Baill. ( G-L ). A. Side view of staminate flower; B. Top view of staminate flower; C. Top view of staminate flower with stamens removed to show the five nectaries; D. Side view of pistillate flower; E. Top view of pistillate flower; F. Top view of pistillate flower with ovary removed to show the five nectaries; G. Side view of staminate flower; H. Top view of staminate flower; I. Top view of staminate flower with stamens removed to show the five nectaries; J. Side view of pistillate flower; K. Top view of pistillate flower; L. Top view of pistillate flower with ovary removed to show the five nectaries. [ A-F: van Ee et al. 2198; G-I: van Ee et al. 2465; J-L: van Ee et al. 2464 ] Fig. 13. – Croton hypochalibaeus Baill. A. Habit ; B. Stem (diam. c. 2.5 cm) with cauliflorous flowers; C. Close-up of the underside of a leaf; D. Staminate flower; E-F. Pistillate flowers; G-H. Fruits. [Photos: P . Berry] Phenology . – Based on the few known collections, Croton lasiopyrus does not appear to be a prolific flowerer. There are remains of staminate flowers, as well as a fruit and a dehisced capsule, from August, with additional flowering collections in April, August, November, and December. Distribution, habitat and ecology . – Croton lasiopyrus grows in ravines and the understory of montane moist forests on the eastern side of Madagascar , in Antananarivo and Toamasina Prov. , at altitudes of 900-1200 m . ( Fig. 1C ). Notes . – Key distinguishing characters of C. lasiopyrus include the rusty, woolly pubescence on the stems and leaves, the short-petiolate, elliptic to ovate, acuminate-tipped leaves, the new leaves tightly clustered at a node and often anisophyllous (of different sizes in the same pair or cluster), and the short inflorescences that appear axillary in the leaf clusters ( Fig. 14 ). The syntype Scott-Elliot 1557 is not this species at all, but rather C. cassinoides Lam. , from the Fort Dauphin area of Toliara Prov. There is another Scott-Elliot specimen from Fort Dauphin that is close to, but probably not conspecific with, C. lasiopyrus , namely Scott-Elliot 2699 (K, P), so there may have been a mix-up in the numbers cited by BAILLON (1890). Two collections ( van Ee et al. 2215 and 2216 ) from the forest north of Route Nationale 2 between Andasibe and Ambatovy share many characters with C. lasiopyrus ( 18°54’57”S 48°20’43”E , 978 m , 14.VIII.2015 , MICH, MO, P, TAN), but they were growing in close proximity to denser populations of C. enigmaticus , and we suspect they may be the result of introgression with that species. This is evidenced by noticeably serrate and acuminate-tipped leaves, more stipitate petiolar glands, and somewhat larger inflorescences and longer pistillate pedicels. Additional specimens examined. – MADAGASCAR . Prov. Antananarivo : Analamanga Region . La Mandraka , 7.II.1937 , Herb. Jard. Bot. Tan. 2380 ( P ); ibid. loc. , 7.XII.1959 , Schlieben 8140 ( G , K ); ibid. loc. , 8.X.1961 , Service Forestier 20332 ( G , K , MO , P ). Prov. Toamasina : Alaotra-Mangoro Region , [ Ambatondrazaka Distr. ], forêt d’Ambodipaiso , près d’Antsevabe , 1200 m , 12.I.1945 , Cours 2293 ( K , MO , P ); Anony , forêt du N aux confins du pays Sihanaka , [ 17°13’S 48°32’E ], 3.IX.1937 , Herb. Jard.Bot.Tan. 2957 ( P ); Moramanga Distr. , Ambohibolakely , Corridor Forestier Analamay Mantadia , forêt d’Amboasary , 1019 m , 25.IV.2012 , 18°47’11”S 48°23’00”E , Rakotovao 5812 ( MO , P , TAN ); Lakato , forest E of Manasamena village, along the Ankandrabe trail , 1062-1100 m , 2.VI.2007 , Randrianasolo et al. 1148 ( MO , P , TAN ); along road to Lakato , 1080 m , 19°03’10”S 48°22’20”E , 11.XI.2003 , Schatz et al. 4186 ( MO , P ); ibid. loc. , 1022 m , 19°02’47”S 48°21’25”E , 27.II.2009 , van Ee et al. 978 ( MICH , MO , P , TAN ); ibid. loc. , 1022-1038 m , 19°02’52”S 48°21’24”E , 13.VIII.2015 , van Ee et al. 2197 ( MICH , MO , P , TAN ); ibid. loc. , van Ee et al. 2204 ( MICH , MO , P , TAN ).