A re-evaluation of the Abutilothamnus complex (Malvaceae) I. Two new species and two new genera, Sidasodes and Akrosida PAUL A. FRYXELL AND JAVIER FUERTES l

Fryxell, P. A. (U.S. Dept. of Agriculture, Agricultural Research Service, in cooperation with Texas A&M University, College Station, TX 77843-2474, U.S.A.) and J. Fuertes (Real Jardin Bot~nico, C.S.I.C., Plaza de Murillo, 2, 28014 Madrid, Spain). A re-evaluation of the Abutilothamnus complex (Malvaceae) I. Two new species and two new genera, Sidasodes and Akrosida. Brittonia 44: 436-447. 1992.--A revision of certain generic boundaries within the tribe Malveae is made. A new genus, Sidasodes, is described with two species, one of which is new, Sidasodes eolombiana. Akrosida is segregated as a new genus, based on Bastardia macrophylla. The new realignment also recognizes Tetrasida as a distinct genus, and describes as new Tetrasida serrulata. New combinations include Sidasodes jamesonii (based on Sida jamesonii), Akrosida macrophylla (based on Bastardia macrophylla), and Tetrasida chachapoyeosis (based on Sida chachapoyensis). Key words: Malvaceae, South America, Abutilothamnus, Tetrasida, Sidasodes,

Akrosida.

Generic boundaries in the tribe Malveae have been one o f the most challenging problems to solve in the systematics o f the Malvaceae. Baker (1890-1894) first attempted to deal with this question, and m o r e recently Bates (1968) and Bates and Blanchard (1970) developed a system o f generic alliances that considerably clarified the obscure t a x o n o m ic landscape o f the tribe. Additional contributions were made by Fryxell (1978, 1988) in delimiting Sida Linnaeus and related genera. In this series we address some o f the unresolved problems o f generic delimitation and relationships within the tribe Malveae. A group o f eight species was treated by Krapovickas (1969) as Abutilon Miller sect. Tetrasida (Ulbr.) Krapov. Three o f the species t r e a t e d b y K r a p o v i c k a s [Abutilon chachapoyense (E. G. Baker) Krapovickas, Abutilon claussenii Krapov., and Abutilon Present address: Instituto de Ciencias Naturales, Universidad Nacional de Colombia, Apartado Atreo 7495, Santaf6 de Bogota, Colombia.

pulverulentum Ulbr.] will be discussed in the present paper. The other five species included by Krapovickas [Abutilon grewiifolium (Ulbr.) Krapov., Abutilon myrianthum (Planchon & Linden) Krapov., Abutilon tulla (Ulbr.) K r a p o v . , Abutilon turumiquirense Steyerm., and Abutilon virginianum Krapov.] plus an additional species described as Abutilothamnus yaracuyense Fryx. (Fryxell, 1985a) will be dealt with in a second paper; three others are described herein, and two m o r e will be added in the forthcoming publication, further enlarging the group to 13 species. This enlarged group is referred to here as the "'Abutilothamnus c o m p l e x " for c o n v e n i e n c e . Species in this group have variously been assigned by different authors to the genera Sida, Abutilon, Tetrasida Ulbr., Bastardia K u n t h , a n d Abutilothamnus U l b r . T h e proper generic or sectional allocation o f these species has remained unsettled, as has the question o f the n u m b e r o f genera i n v o l v e d and the generic delimitation o f those accepted. Recent discoveries (both o f new taxa

Brittonia, 44(4), 1992, pp. 436-447.

9 1992, by the New York Botanical Garden, Bronx, NY 10458-5126

ISSUED: 11 December 1992

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FRYXELL & FUERTES: THE ABUTILOTHAMNUS COMPLEX

a n d n e w characters) h a v e led to a r e c o n s i d e r a t i o n o f this g r o u p a n d to t h e f o l l o w i n g revised interpretation. The present study deals w i t h t a x a b e l o n g i n g to the S i d a alliance, a n d a s e c o n d p a p e r (in p r e p a r a t i o n ) will deal w i t h t a x a i n t h e A b u t i l o n alliance, as these a l l i a n c e s are d e l i n e a t e d i n Bates

437

(1968) a n d Bates a n d B l a n c h a r d (1970) a n d m o d i f i e d b y F r y x e l l (1978, 1988). F o r ease o f reference i n t h e s u b s e q u e n t d i s c u s s i o n , a key to the g e n e r a o f t h e S i d a a l l i a n c e is pres e n t e d here, w h i c h also serves to h i g h l i g h t the differences a m o n g t h e s e genera.

K e y to t h e g e n e r a o f the S i d a a l l i a n c e 1 Prostrate perennial herbs; calyx often accrescent. 2 Leaves asymmetrical; calyx accrescent or not. 3 Involucel sometimes present; pubescence stellate to more or less lepidote; leaves asymmetrically reniform or triangular; calyx not accrescent; carpels 7-10 ....................................................Malvella Jaub. & Spach 3 Involucel absent; pubescence of simple hairs; leaves asymmetrically ovate-cordate; calyx accrescent; carpels 5 ........................................................................................................................................................................................Sida [l"ussieana DC.] 2 Leaves symmetrical; calyx notably accrescent and inflated. 4 Calyx at fruit maturity becoming brown-membranous by disintegration of all but the finely reticulate vasculature; mericarps relatively fragile-walled and unornamented ..............Krapovickasia Fryx. 4 Calyx remaining green at fruit maturity; mericarps indurate, the lateral walls prominently retieulate-fenestrate, with a prolonged horizontal rostrum .............................................................................Rhynchosida Fryx. 1 Erect trees, shrubs, or subshrubs (if prostrate herbs, then leaves symmetrical and calyces not accrescent); calyces not accrescent. 5 Calyx basally 10-ribbed or -angled, the commissural nerves often more prominent than the midribs. 6 Trees or large shrubs 3-10 m tall; petals yellow or red, 1.5-4 cm long; mericarps more than 5 mm long ............................................................................................................................................................................................................ Dendrosida Fryx. 6 Subshrubs or herbs, usually less than 2 m tall; petals yellow or orange, less often white or lavender, usually less than 1.5 cm long (rarely to 2 cm); mericarps less than 5 mm long ........................................Sida L. 5 Calyx basally rounded, not ribbed (although the lobes sometimes 3-nerved). 7 Subshrubs 1-3 m tall, usually single-stemmed; petals less than 1 cm long; inflorescences usually terminal panicles. 8 Mericarps with smooth lateral walls, with a small internal endoglossum; leaves broadly ovate ...................................................................................................................................................................................................... Allosidastrum Krapov. et al. 8 Mericarps smooth or weakly reticulate laterally; endoglossum absent; leaves narrowly elliptic to ovate ............................................................................................................................................................................................Sidastrum E. G. Baker 7 Robust shrubs or small trees, usually well-branched and more than 3 m tall; inflorescences usually axillary. 9 Petals bluish, basally bi-auriculate, the auricles densely pubescent; flowers in axillary fascicles .............................................................................................................................................................................................................. Akrosida Fryx. & Fuertes 9 Petals pale lavender (or whitish) or yellow, lacking auricles; flowers in axillary racemes or these forming terminal inflorescences. 10 Corolla yellow; calyx 4 mm long, shallowly lobed; flowers on slender pedicels 0.5-2 cm long; leaves ovate-elliptic; plants stellate-puberulent ......................................................................Tetrasida Ulbr. 10 Corolla pale lavender (or whitish); calyx 7-9 mm long, deeply lobed; flowers subsessile; leaves angulate to weakly 3-lobed; plants coarsely pubescent, the hairs often stipitate ..... .............................................................................................................................................................................................. Sidasodes Fryx. & Fuertes

Sidasodes K r a p o v i c k a s ' (1969) t r e a t m e n t o f A b u t / Ion p u l v e r u l e n t u m U l b r . was b a s e d o n t h e e x a m i n a t i o n o f a single s p e c i m e n ( L f p e z & S a g f s t e g u i 5479), w h i c h l a c k e d m a t u r e fruits. T h e m o r e r e c e n t c o l l e c t i o n o f f r u i t i n g s p e c i m e n s (cited below), w h i c h were n o t a v a i l a b l e to K r a p o v i c k a s , a n d the d i s c o v e r y o f a n u n d e s c r i b e d r e l a t e d species, h a v e m a d e it n e c e s s a r y to m a k e a n e w t a x o n o m i c disp o s i t i o n o f these p l a n t s .

A n e x a m i n a t i o n o f t h e fruits s h o w s t h e m to differ clearly f r o m o t h e r species o f t h e Abutilothamnus complex in being glabrous o r n e a r l y so a n d i n h a v i n g t h e " s i d o i d " m o r p h o l o g y o f the m e r i c a r p s , i n w h i c h t h e d o r sal wall is clearly d i f f e r e n t i a t e d f r o m t w o lateral walls. O t h e r species o f this c o m p l e x h a v e the " a b u t i l o i d " f o r m , i n w h i c h t h e m e r i c a r p has a d o r s a l keel (often the l i n e o f dehiscence) b u t n o differentiated dorsal wall. T h e s e t w o types o f m o r p h o l o g y m a y b e de-

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scribed as trigonal vs. elliptic in cross-section. This morphological difference distinguishes two genetic alliances (Fryxell, 197 l, 1988). By analogy, we conclude that Abutilon pulverulentum is not congeneric with other species of Abutilon sect. Tetrasida, as interpreted by Krapovickas. The question then becomes: T o what genus (if any) o f the Sida genetic alliance do these plants conform? N o n e o f the eight genera o f this alliance (Fryxell, 1988) seems to a c c o m m o d a t e it. The fruit m o r p h o l o g y o f the plant in question is suggestive o f that o f Sida hermaphrodita (L.) R u s b y o f the m o n o t y p i c Sida sect. Pseudo-Napaea A. Gray (Fryxell, 1985b), but little else about morphology, growth habit, or geography supports the inference o f a t a x o n o m i c relationship between these two plants. (Indeed, Sida sect. Pseudo-Napaea remains anomalous in the present treatment; it would come out near couplet 8 in the preceding key to genera, but this presents a misleading idea o f its affinities.) T h e genera Meximalva Fryx., Krapovickasia Fryx., Rhynchosida Fryx., Sidastrum E. G. Baker, Allosidastrum Krapov. et al., and Malvella Jaub. & Spach are sufficiently different from the plant under consideration here (see genetic key) to be eliminated virtually without c o m m e n t . There remains the genus Dendrosida Fryx. (Fryxell, 1988; Fuertes, 1989), with which it shares a relatively robust growth habit. The general aspect o f the plant, however, does not support a placement in the genus Dendrosida, and characters such as pubescence type and inflorescence structure

[VOL. 44

(Fryxell, 1971, 1985a; Fuertes, 1 9 8 9 ) a l s o argue against such a placement. We therefore believe that the species concerned deserves to be segregated at the genetic level, the new genus pertaining to the Sida generic alliance. Sidasodes Fryx. & Fuertes, gen. nov. TYPE: Sidasodes jamesonii (E. G. Baker) Fryx. & Fuertes. Frutices pills stellatis luteolis dense obtectis; laminis foliorum ovatis vel leniter 3-1obulatis; inflorescentiis axillaribus vel terminalibus ramificantibus subcorymbosae, calycibus profunde partitis; petalis violaceis vel albidis; fructibus glabris, mericarpiis 10-12 in sectione transversali trigonis, pariete dorsali a parietibus lateralis differentibus; seminibus solitariis. Shrubs densely covered with yellowish stellate hairs; leaf blades ovate or weakly 3-1obulate; inflorescences axillary or terminal, s u b c o r y m b o s e l y b r a n c h e d ; calyx deeply lobed; petals lavender or whitish; fruits glabrous, the 10-12 mericarps each trigonal in cross-section, the dorsal wall differentiated f r o m the two lateral walls; seeds solitary. The distinguishing features o f Siclasodes include the robust growth habit; the distinctive stellate pubescence, frequently including stipitate hairs; and the long-pedunculate, a x i l l a r y i n f l o r e s c e n c e s t h a t are subcapitate in flower but b e c o m e m o r e open in fruit by elongation o f the pedicels. It occurs at elevations o f ( 1 8 0 0 - ) 2 3 0 0 - 2 9 0 0 m, from C o l o m b i a to Peru. The habitat o f both species seems to be disturbed places on high slopes o f interandean valleys.

Key to species o f Sidasodes 1 Inflorescencesshorter than the subtending leaf; calyx costate, open when fruiting; apex of calyx lobes acute; mericarps with apical zone of the dorsal wall concave (Colombia) ..................................................S. colombiana 1 Inflorescenceslonger than the subtending leaf; calyx ecostate, closed when fruiting; apex of calyx lobes long-acuminate; mericarps with the whole dorsal wall convex (southern Ecuador, Peru) ............S. jamesonii Sidasodes colombiana Fryx. & Fuertes, sp. nov. (Fig. 1) TYPE: COLOMBIA. Depto. Boyacfi: entre Soatfi y Cocuy, Valle de la Uvita, E1 Hatico, 2900 m, Cuatrecasas 1165 (I-IOLOTVPE: COL!; ISOTYPES"F! US!).

Frutex erectus dense stellato-pulverulentis, foliis ovatis ad apicem ramis congestis, 16 cm usque longis cordatis acuminatis irregulariter bidentatis valde discoloribus aliquantum 3-5-1obatis supra glabris subtus dense stellato-pubescentibus. Inflorescentiae racemosae subcorymbosae axillares, pedicellis usque 3 mm longis. Calyx semidivisus apertus in fructificatio, lobis acutis 5-costatis subcucullatis in fructificatio. Corolla

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FRYXELL & FUERTES: THE ABUTILOTHAMNUS COMPLEX

439

FIG. 1. Sidasodes colombiana. A. Flowering branch. B. Inflorescence. C. Calyx. D. Fruit with calyx partially removed. E. Mericarp in lateral, ventral, and dorsal views.

440

BRITTONIA

rosea vel albida. Fructus schizocarpicis,mericarpiis ca. 12 apiculatis apicem versus coneavis, in sectione transversali trigonis, ad apicem dehiscentibus, seminis solitariis glabris. S h r u b s ca. 3 m tall, the stems densely pulverulent, the hairs stellate, ca. 0.3 m m long with m o r e than 10 radii. L e a f blades mostly 5-16 cm long, 3-10 cm wide, ovate or weakly trilobulate, cordate, irregularly crenate-biserrate, acute to acuminate, palmately 5-9-nerved, markedly discolorous, the upper surface with scattered appressed simple, bifurcate, or stellate hairs (or the upper surface glabrate), densely steUate-pubescent on main veins, the lower surface stellate-tomentose (densely so when young); petioles 1/4-1/2times length o f blade, densely pulverulent. I n f l o r e s c e n c e s cymose, axillary, the peduncles densely pulverulent, shorter than or slightly surpassing the subtending petiole, shortly branched in cymes o f 3--4 flowers; flowers sessile or subsessile, congested at the end o f the branch or subtended by a floral bract, the bract ovate, 1.72 m m long, 0.8 m m wide, early deciduous; calyx 7-9 m m long, open when fruiting, half or more divided, the lobes acute, costate, the apex massive, cuspidate, subcucullate when fruiting, the outer surface densely stellate-pubescent, the inner surface glabrous; corolla rotate, lavender to whitish, the petals ca. 1 c m long, with a barbate ring o f simple hairs at the base o f the staminal tube, the staminal c o l u m n otherwise glabrous. F r u i t s oblate, umbonate, 4 m m long, enclosed in calyx, glabrous; mericarps ca. 12, 3 m m long, 2.5 m m wide, 1-1.5 m m thick, shortly apiculate, the dorsal wall apically concave; seeds solitary, ca. 2 m m long, glabrous.

Additional specimens examined: COLOMBIA. Depto. Boyaefi. MPio. LA UVITA: Vereda E1 Hatico, alrededores de la escuela, 2840 m, 1990, Bol&ar 26 (COL); Vereda El Hatico, sector Travesia, 2550 m, 20 Apr 1991, Fuertes et aL 1121 (COL, MA); Vereda E1 Hatico, camino a la escuela, 2800 m, 20 Apr 1991, Fuertes et al. 1122 (COL, MA). The new species is called " m a j a g u a " by people from the type locality, the Valle de La U v i t a in the Cordillera Oriental o f Colombia. T h e n a m e is applied to various other arborescent representatives o f the Malvales in various parts o f tropical America,

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especially those utilized for bast fibers (cf. Fryxell, 1969, p. 365). T h e only use recorded in the region is fairly u n c o m m o n in the Malvaceae: the slender and flexible stems o f S i d a s o d e s c o l o m b i a n a are used for corporal p u n i s h m e n t o f students at the local school. Nests o f h u m m i n g b i r d s were observed in several plants o f one o f the populations studied; they are located under the congested upper leaves, one o f which is used as a " d o o r " to the nest.

Sidasodes jamesonii (E. G. Baker) Fryx. & Fuertes, comb. nov. (Fig. 2) Sidajamesonii E. G. Baker, J. Bot. 30: 324. 1892. TYPE:ECUADOR. Azuay:Cuenca, 6000 ft, Jameson 104 (rlOLOTYPE:K!). Abutilon pulverulentum Ulbr., Bot. Jahrb. Syst. 54 (Beibl. 117): 51. 1916. Sida pulverulenta (Ulbr.)

Kearney, Madrofio 12: 117. 1953. TYPE:PERU. Depto. Cajamarca. Prov. Hualgayoc; fiber S. Miguel, 600-2700 m, Weberbauer 3904 (HOLOTYPE: B--destroyed, as photo F-9286!; ISOTVPE:MOL, fide Raymondiana 2: 138. 1968). S h r u b s ca. 3 m tall, the stems densely yellowish puberulent, the hairs stellate, often stipitate, the stipe ca. 0.3 m m long, then tufted with ca. 10 radii or more. L e a f blades 8-18 cm long, ovate or weakly trilobulate, cordate, irregularly crenate-serrate, acute or acuminate, palmately 5-7-nerved, the upper surface with scattered appressed simple or bifurcate or stellate hairs (or glabrate), densely stellate on main veins, the lower surface stellate-pubescent (densely so when young), markedly discolorous; petioles 1/41/2(-1) times length o f blade, densely puberulent. I n f l o r e s c e n c e s racemose, axillary or terminal, often branched, the peduncles densely pulverulent, the flowers congested at the ends o f the branches; calyx 7-9 m m long, ecostate, the outer surface densely stellate-pubescent, the inner surface glabrous, half or m o r e divided, the apices massive, subcucullate when fruiting, caudate; petals ca. 1 c m long, lavender or whitish, barbate at the claw; staminal column glabrous. Fruits oblate, 5-6 m m long, enclosed in calyx, glabrous; mericarps 10-12, 4 m m long, often shortly apiculate; seeds solitary, ca. 2 m m long, glabrous.

Additional specimens examined: PERU. Depto. Cajamarca. PROV.CAJAMARCA:alrededores de San Pablo,

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FIG. 2. Sidasodesjamesonii. A. Flowering branch. B. Inflorescence. C. Calyx. D. Mericarp in lateral, dorsal, and ventral views. 2340 m, S~nchez 1504 (CPUN, US, pf), Sag(tstegui et al. 7991 (F, HUT, NY, WIS, pf); PROV. CONTUM~: alrededores de Guzmango, 2500 m, Sag6stegui & Mostacero 9170 (HUT, Of), 2700 m, Sag(tstegui et aL 9647 (HUT, pf); PROV. SAN MIGUEL:alrededores de Calquis, 2400 m, Sag6.stegui et aL 8859 (F, HUT).

Akrosida

Another species considered a part of the Abutilothamnus complex is the one treated

by Krapovickas (1969) as Abutilon claussenii Krapovickas. It occurs in southern Brazil and has distinctive floral characters, including a bluish corolla and bi-auriculate petals, with flowers in axillary fascicles. The fruits are schizocarps of five mericarps of the "sidoid" type. The auricles on the petals (Fig. 3E) are unique in the Malvaceae, to our knowledge. Altogether the plants are

442

BRITTONIA

distinctive enough to merit segregation as a distinct genus, in our opinion. Akrosida Fryx. & Fuertes, gen. nov. TYPE: Akrosida macrophylla (Ulbrich) Fryx. & Fuertes (basionym: Bastardia macrophylla Ulbr.). Arbor parva vel frutex. Folia subrhombifolia basi cuneata. Inflorescentia fasciculata in axillis foliorum. Corolla caerulea vel alba. Petala biauriculata, densiter stellato-pubcscentibus in appendicibus. Fructus schizocarpicis, mericarpiis 5, in apex dehiscentibus, in sectione transversali trigonis. Semina solitaria glabra. Small trees or shrubs. Leaves ovate to subrhomboid. Flowers grouped in axillary fascicles. Calyx campanulate, ecostate. Petals white to blue, bi-auriculate, stellate-pub e s c e n t , the auricles s t e l l a t e - p u b e s c e n t . Fruits schizocarpic, the mericarps 5, trigonal in c r o s s - s e c t i o n , a p i c a l l y d e h i s c e n t , 1-seeded. The n a m e is derived from the G r e e k akro (shrub) and the generic n a m e Sida. The n a m e also h o n o r s Antonio Krapovickas, exceptional malvologist, colleague, and friend. As far as we know, the genus is monotypic.

Akrosida macrophylla (Ulbrich) Fryxell & Fuertes, comb. nov. (Fig. 3) Bastardia macrophylla Ulbr., Notizbl. Bot. Gart. Berlin 6: 324. 1915. Abutilon claussenii Krapov., nora. nov., Bonplandia 3: 37. 1969 [non Abutilon macrophyllum St.-Hil. & Naudin]. TYPE: BRAZIL. Edo. Rio de Janeiro: in der Capoeira bei Nova Friburgo, Ule 3630 (HOLOTYPE:B, as photo F-9403~). Bastardia macrophylla forma lanata Monteiro, Bol. Soc. Port. Ci. Nat. 19: 128. 1955. TYPE:BRAZIL. Minas Gerais: Passo Quatro, Esta~o Florestal de Mantiquiera, Silva Araujo & Barbosa 88 (HOLOTYPE:RBR-62757). Small trees or shrubs, the stems with minute stellate hairs, these stipitate or subsessile. L e a f blades broadly ovate, to 16 cm long, 11 cm wide, basally obtuse, irregularly crenate, acute, palmately 5-nerved, discolorous, the upper surface sparsely stellatepubescent, the lower surface velutinous, densely stellate-tomentose, the veins p r o m inent; petioles to 9 cm long, with i n d u m e n t like that o f stems; stipules filiform, ca. 5 m m long, caducous. Flowers grouped in axillary

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fascicles, subumbellate; pedicels 2-3.5 cm long, articulate in the upper third, stellatetomentulose; calyx campanulate, ecostate, 4-5 m m long, the lobes deltate, 2-2.5 m m long, the outer surface stellate-tomentulose, the inner surface glabrous, with a basal nectariferous disk ca. 1 m m in d i a m e t e r composed o f 5 nectaries; petals asymmetrically emarginate, 8 m m long, 6 m m wide, biauriculate, the outer surface minutely stellate-tomentose, the inner surface glabrous, the auricles densely stellate-tomentose; staminal c o l u m n ca. 3 m m long, densely stellate-tomentose at the base; styles 5, ca. 5 m m long, t h e stigmas c a p i t a t e . Fruits schizocarpic; mericarps 4 m m long, 3 m m wide, muticous, apically dehiscent, trigonal in cross-section, the apex and dorsal wall densely stellate-tomentose; seeds solitary, reniform, with scattered simple hairs at the apex. Although several characters o f Akrosida superficially suggest Abutilon, there are reasons to consider it as a separate genus in the Sida alliance. For instance, the ring o f hairs a r o u n d the base o f the staminal c o l u m n resembles that found in the Abutilon pubistamineum Ulbrich group o f species; however, in these species the nectariferous structure is c o m p o s e d o f simple hairs rather than stellate hairs, as are present in Akrosida. The bluish corolla is u n c o m m o n in shrubby plants (Gottsberger & Gottlieb, 1981), being found in the neotropical Malvaceae only in some species o f the herbaceous genus Anoda Cav. (Fryxell, 1987), occasionally in Sphaeralcea spp., and in the arborescent Middle American genus Robinsonella Rose & E. G. Baker (Fryxell, 1973), but not found in representatives o f the Abutilon alliance. The pubescent dual auricles on the petals (Fig. 3E) are apparently unique to Akrosida. Unilateral auriculae are characteristic o f the unrelated genus Malvaviscus, but they are morphologically very different f r o m those of Akrosida, and basal petal appendages are otherwise u n k n o w n (to our knowledge) in the family Malvaceae. Mericarp m o r p h o l ogy and dehiscence d e a f l y argue in favor o f a " s i d o i d " placement. There remains the possibility o f a distant relationship of Akrosida with the genus Robinsonella.

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FIG. 3. Akrosida macrophylla. A. Flowering branch. B. Leaf blade. C. Inflorescence. D. Flower. E. Base of petal, showing pubescent auricles. F. Fruit with calyx partially removed. G. Mericarp in dorsal, lateral, and ventral views.

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BRITTONIA Tetrasida

Among the remaining species of the Abutilothamnus complex, there is yet another species belonging to the Sida alliance. We prefer to recognize this plant in generic rank, following Kearney (1951) and Hutchinson (1967), under the name Tetrasida Ulbr., and we subsequently add a second species. Rec-

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ord and Hess (1937) provide some descriptive data about the wood anatomy of Tetrasida (presumably T. polyantha Ulbr.) but in the absence of comparative data it is difficult to evaluate its taxonomic significance. It may be noted that the basis for the generic name, the tetramerous calyx, is an inconstant character and that the calyx of T. serrulata is pentamerous.

Key to the species of Tetrasida 1 Leaves entire; petals l0 mm long; styles and mericarps 5; mericarps 1-celled, lacking an endoglossum ........................................................................................................................................................................................................................... T. chachapoyensis 1 Leaves serrulate; petals 5-6 mm long; styles and mericarps 9-10; mericarps divided into two cells by a stiff endoglossum ............................................................................................................................................................................................................... T. serrulata

Tetrasida chachapoyensis (E. G. Baker) Fryx. & Fuertes, comb. nov. (Fig. 4) Sida chachapoyensis E. G. Baker, J. Bot. 30: 324. 1892. Abutilon chachapoyense (E. G. Baker) Krapov., Bonplandia 3: 34. 1969. TYPE: PERU. Chachapoyas, near Sesuya, Matthews 3049 (HOLOTYPE: K!; ISOTYPE."OXF!). Tetrasida polyantha Ulbr., Bot. Jahrb. Syst. 54 (Beibl. 117): 66. 1916. TYPE: PERU. Cajamarca. Prov. Ja6n: Tal des Marafion, zwischen Ja6n und Bellavista, 600 m, Weberbauer 6208 (ISOTYPES:GH!

usD. Small trees or shrubs to 5 m tall, the stems covered with minute stellate hairs. L e a f blades ovate to elliptic, to 11 cm long, 6 cm wide, basally subcordate, entire, acute or obtuse (sometimes retuse), palmately 7-nerved, discolorous, the upper surface with sparse, minute stellate hairs, the lower surface densely and minutely stellate-tomentose, the veins prominent; petioles to 3 cm long, with indument like that of stem; stipules ca. 3 m m long, caducous. Flowers in terminal panicles; pedicels 10-20 mm long, articulated near middle or above, minutely stellate-tomentose; calyx campanulate, ecostate, ca. 4 m m long, 4-5-lobed, the lobes ca. 2 m m long, the outer surface stellate-tomentose, the inner surface glabrous with a ring-shaped basal nectary composed of long glandular hairs; corolla rotate, yellow; petals 5, ovate, 10 m m long, 7 mm wide, symmetric, with stellate hairs on margins of claw, otherwise glabrous; staminal column 2-3 m m long, glabrous, the anthers 20-30; styles 5, ca. 6 m m long, surpassing the stamens, with capitate stigmas. Fruits

schizocarpic; mericarps 5, trigonal in crosssection, apically dehiscent, densely stellatetomentose; seeds solitary, reniform, brown, with arachnoid pubescence of stellate hairs. Additional specimens examined: PERU. Depto. Amazonas: 5 km E of Bagua on road to La Peca, Mara-

fi6n Valley, Gentry, Dillon, Aronson & Dfaz 22788 (F, MO, USM, pf); PROV. BAGUA:carretera hacia Luya, entre Chilefia y Zapatalgo, Dfaz & Campos 3674 (MO, pf). Depto. Cajamarca. PROV. JAI~N:Rio Chamaya, km 180 E of Olmos, ca. 53 km E of Pucarfi, Hutchison & Wright 5876 (BH, F, G, GH, HEID, K, LE, M, MICH, MO, NY, P, S, US, USM); Km 27 E of Pucarfi, along Rio Huancabamba, Chiple, Plowman, SagdsteguL Mostacero, Mejia & Peldez 14259 (F, HUT, pl); 32 km E of Pucar~, along Rio Huancabamba, Gentry, Dillon, Aronson & Dfaz 22753 (F, MO, USM, pf); PucarfiChamaya, L6pez, Sagdstegui, Mostacero & L6pez 8958 (HUT, pf).

Among the materials examined are specimens that represent an undescribed species, the description of which follows. Tetrasida serrulata Fryx. & Fuertes, sp. nov. (Fig. 5) TYPE: PERU. Depto. Cajamarca. PROV. CELENDiN: Balsas-Celendln road, 1-5 km from Balsas (78~ 6~ O'S), 910-1160 m, desert slopes, Rio Marafion Valley, 23 Feb 1984, D. N. Smith 6165 (HOLOTYPE: MO!; ISOTYPES" USM, pfl). Frutices caulibus dense puberulis; laminis foliorum ovatis serrulatis molliter puberulis; inflorescentiis axillafibus inflorescentiam compositam supra folia facientibus; calycibus ecostatis; petalis flavidis; fructibus oblatis vel subglobosis pubescentibus, mericarpiis 910 in 2 cellulis per endoglossum rigidum divisis; seminibus in cellula inferiore solitariis.

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FIG. 4. Tetrasidachachapoyensis. A. Flowering branch. B. Flower. C. Inflorescence. D. Fruit. E. Mericarp external and internal views. F. Seed.

Shrub 1-1.6 m tall, the stems densely puberulent, the hairs 0.1-0.3 m m long, stellate, yellowish. Leaf blades mostly 3-5 cm long, 2.5-4 cm wide, ovate, basally cordate, serrulate, acute or somewhat acuminate, palmately 7-9-nerved, m o r e or less discolorous, densely and softly puberulent above and beneath; petioles 0.5-2 cm long, with pubescence like stem; stipules 2-3 m m long, subulate, caducous. Inflorescences in the axils o f the u p p e r m o s t 3-5 leaves, long-ped u n c u l a t e , r a c e m o s e l y or s u b c y m o s e l y

branched, the aggregate (more or less pan i c u l a t e ) i n f l o r e s c e n c e o v e r t o p p i n g the leaves; peduncles mostly 2-6 cm long, supporting 6-12 flowers each; pedicels 0.5-1.5 cm long, puberulent; calyx 4 m m long, basally rounded, ecostate, puberulent, ca. halfdivided, pentamerous, the lobes triangular; petals 5-6 m m long, 3-4 m m wide, yellow or orange-yellow, glabrous; staminal colu m n ca. 2 m m long, stellate-pubescent, pallid, the filaments ca. 1 m m long; styles 9 1O, slender, slightly exceeding the androe-

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FIG. 5. E. Seed.

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Tetrasida serrulata. A. Flowering branch. B. Flower. C. Fruit. D. Mericarp in dorsal and lateral views.

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cium, the stigmas truncate or subcapitate. Fruits oblate to subglobose, densely stellatepubescent, 5-6 m m in diameter; mericarps 9-10, divided into two cells by a stiff endoglossum inserted dorsally; seeds [immature] solitary in the lower cell, glabrous. Additional specimens examined: PERU. Depto. Amazonas. PROV. BAGUA: entre Bagua Grande y Chamaya, 22 Abril 1964, Ferreyra 15639 (US). Depto. Cajamarca. PROV. JA~N: road from Olmos to Pucarfi, km 97 E of Olmos, along Rio Huancabamba, 950 m, dry forest, 11 July 1986, Plowman et al. 14226 (F, HUT, PO. Depto. La Libertad. PROV. PATAZ: ChagualRetamas, carretera a Tayabamba, Ltpez & Sagdstegui 8278 (HUT, NY). Depto. San Martin: Alto Rio Huallaga, 360-900 m, LI. Williams 6663 (F).

The inclusion of Williams 6663 under T. serrulata is provisional, in that the specimen is incomplete. However, if it is correctly placed here, it resolves questions raised by Macbride (1956, p. 592) and Krapovickas (1969, p. 37) concerning the taxonomic placement of this collection. There is a marked resemblance between the new species and the type species of Tetrasida, T. polyantha Ulbr., particularly in the aspect of the flowers and the presentation of the inflorescences. They differ, however, in that the new species has smaller flowers, serrulate leaves, more numerous carpels, and mericarps with an endoglossum. It may be noted, however, that dissection of the carpels of the latter species reveals a vestigial upper cell and the suggestion that an endoglossum has been suppressed.

Acknowledgments We thank the curators of the cited herbaria for loans of specimens and Juan Carlos Pinz6n and William Oliveros for their skillful drawings. Fuertes thanks A.E.C.I. (Spanish Agency for International Cooperation) for support of the fieldwork in Colombia and Leonardi Bolivar for his help

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in the location of populations of Sidasodes colombiana.

Literature Cited Baker, E.G. 1890-1894. Synopsis of genera and species of Malveae. J. Bot. 28: 15-18, 140-145, 207, 213, 239-243, 339-343, 367-371; 29: 49-53, 164172, 362-366; 30: 71-87, 136-142, 235-240, 290296, 324-332; 31: 68-76, 212-217, 267-273, 334338, 361-368; 32: 35-38, 186. Bates, D . M . 1968. Generic relationships in the Malvaceae, Tribe Malveae. Gentes Herb. 10:117-135. - & O. J. Blanchard, Jr. 1970. Chromosome numbers in the Malvales II. New or otherwise noteworthy counts relevant to classification in the Malvaceae, tribe Malveae. Amer. J. Bot. 57: 927-934. Fryxell, P . A . 1969. The genus Hampea. Brittonia 21: 359-396. - - . 1971. A new genus from Mexico: Dendrosida (Malvaceae). Brittonia 23:231-237. 1973. A revision of Robinsonella Rose & E. G. Baker (Malvaceae). Gentes Herb. 11 : 1-26. 1978. Neotropical segregates from Sida L. (Malvaceae). Brittonia 30: 447-462. 1985a. Four new species of Malvaceae from Venezuela. Syst. Bot. 10: 273-281. 1985b. Sidus sidarum V. The North and Central American species of Sida. Sida 11: 62-91. 1987. A revision of the genus Anoda (Malvaceae). Aliso 11: 485-522, 1988. Malvaceae of Mexico. Syst. Bot. Monogr. 25: 1-522. Fuertes, J. 1989. Una nueva especie de Dendrosida (Malvaceae) de Colombia. Revista Acad. Colomb. Ci. Exact. 17: 375-378. Gottsberger, G. & O. R. Gottlieb. 1981. Blue flower pigmentation and evolutionary advancement. Biochem. Syst. Ecol. 9: 13-18. Hutchinson, J. 1967. The genera of flowering plants, Vol. 2. The Clarendon Press, Oxford. Kearney, T . H . 1951. The American genera of Malvaceae. Amer. Midl. Naturalist 46:93-131. Krapovickas, A. 1969. Notas sobre el gtnero "Abutilon" Mill. (Malvaceae) I. La secci6n Tetrasida (Ulbr.) Krap. Bonplandia 3: 25-47. Macbride, J. F. 1956. Flora of Peru -- Malvaceae. Field Mus. Nat. Hist., Bot. Set. 13 (part 3A, no. 2): 442-593. Record, S. J. & R. W. Hess. 1937. Aids in identifying American timbers of the order Malvales. Trop. Woods 51: 1-10.