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BULL BOT. SURV. INDIA Vol. 5, No. 1 :pp. 67-70, 1963 THE GENUS STRIGA LOUR IN WESTERN INDIA C. J. SAWANHA,S. 3. St. Xavicr's Collsgc, Bornbqy ABSTRACT The nomenclature of the Strigae is unsatisfactory. The name Strign asiatica has been a source of confusion as the original description is ambiguous and the Linnaean plant material is a mixture of several species. This name comes under purview of Art. 69 of the Code aM1 has, therefore, been rejected. A study of the type material and of the original description of Buchwa CUPL& Vahl indicate that it is quite distinct from StrQ cuptaJioidas Benth. According to Art. 55 df the Code 'the ,name Shign nrptasioides (Vahl) Benth. has to be restricted to Vabl'e plant. The plant commonly called Sfriga mphrasioi&s Benth. has been renamed as Slriga angtutyoib (Don) wmb. nov. The third part of the paper gives a dichotomous kq, the nomenclature of and di& tributional notes to the 5 species of Striga occurring in the wet, western part of peninsular. India. The genus Striga Lour. belonging to the family species of Striga, i.e. densiflora, euphrasioides, Scrophulariaceae, has received a good deal of atten- hirsuta and thunbergii. tion in recent years especially with regard to its The Linnaean binomial was recombined as Striga physiology and control. Unfortunately, the nomen- asiatica (L.)0. Kuntze, Rev. Gen. P1. 2 : 466, 1891. clature of the group is confusing and adversely Hochreutiner holds that this combination applies effects research carried on in other branches of to S. demiflora Benth. He observes in Candollea 5: Botany and Agriculture. We hope to throw some 2x0, 1934, Zint semble avoir effectivement con- light on the taxonomy of this fondu lm S. densiflora et lutea et 0.Kuntze a pu In this paper, we shall first s!z- ow that the name reprendre avec raison le nom linnCen de ahkca S.rriga asiatica (L.) 0. Kuntze has to be rejected. pour leS. densifIora Benth.' Next, we shall propose a new name for the ~lant It would seem, from the passage just cited, that usually called S. euphrasioides Benth. In the third S. asiatica (L.) 0.Kuntze should denote S. densifiara part we shall present a systematic study of the Benth. Merrill, however, is of quite a different genus as represented in the wet part of peninsular opinion. As he sees it, Linnaeus' descri tion refers Western India. to.. S. lutea Lour. Merrill writes in 8rans. Am. Linnaeus described a plant called Buchnera Phil. Soc. 24(z) : 353, 1935, 'Buchnera asMtzca Linn. asiotica in Sp. P1. 630, 1753. His description runs was based on actual specimens from China ' and as follows : 'Buchnera (asiatica) foliis integerrimis Ceylon, Bentham stating that the material in thc alternis. Habitat in Zeylona, China. Caulis ramis Linnaean herbarium is in part S. hirsuta Benth, and alternis, habitu Euphrasiae, obtuse tetragonus. art S. densiflora Benth. Linnaeus' description Folia lineari-lanceolata, scabra, integerrima, alterna inapp ! 'es to the former, i.e. the form described bg versus basin opposita. Spicae longae floribus Loureiro as S. lutea.' For Merrill, then, S. a.datba alternis remotis. Calyces quinquepartiti, scabri : (L.) 0. Kuntze refers to S. lutea Lour. Tubus corolIae filiformis, calyce duplo longior, Pennell has taken up a third position, In Acad. cervice incurvato, stamina 4 includente ; Limbus Nat; Sc. Phil. Mon. 5 : 96, 1943 he remarks, 'I think quinquefidus, purpureus ; laciniis 2 superioribus that the description (Linnaeus') of th'e stem as brevissimis reflexis ; tribus reliquis obovatis subae- obtusely tetragonous,. of the leaves as linear- qualibus.' lanceolate and scabrous, and of the corolla-limb as This diagnosis is as ambiguous as it can be, and purple, best denotes the species now considered, the has been applied to different species. Linnaeus did plant that Bentham called S. euphrasioides.' not mention any specimen or figure that could be According to Pennell, therefore, S. asiatica (L.) considered a type. The material in the Linnaean 0. Kuntze is the correct namdor S. euphrasioides 3erbafium, indentifed in part by Linnaeus himself, Benth. lncludes more than one species. Bentham studied The fundamental cause of all this confusion is these spec- adobserved in Hook. Comp. Bot. the imprecise nature of the Linnaean description Mag. : 366 1836, 'I find from his (Linnaeus' and the lack of an authentic type. Any attempt that he applied that name (Bwk neraher- to decide on a kctotype is bound to be arbitrary wtzca) all. the Sldgm he was acquainted withs. and open to question. Under these circumstances, Subequently~in his revision of &is genus in DC, Striga asiatka (L.) 0.Kuntze certainly earn& under Pdl= 10: 502-503, 1846, Bentham cited Buchnera the purview of Art. 69 of the Code which states, &&CU L. ex weas. a spnanym under different 'A name must be rejected if it is used in different 68 BULLETIN OF m$ BOTANICAL SURVEY OF mu [Vol. 5 senses and so has become a long-persistent source leading to insist merely on the nuxnber of the calyx- of error.' In accordance with this ruling and to ribs in delimiting the species. Striga lutea Lour., avoid further confusion, we consider S. aszatica (L.) which is usually said to have lo ribs, has been found 0. Kuntze as well as its basionym," nomirua rejicl- to have as many as 17. Similarly, S. gesnerioides enda. (Willd.) Vatke may have 4-8 ribs depending on the The various plants that have been called Striga number of properly developed calyx-lobes. More asiatica (L.)0. Kuntze have to be named according importance should be given to the position of these to the rules of priority. As for the 4 species men- ribs than to their *mere number. tioned by Bentham, S. hirsuta Benth. (1846) becomes a synonym of S. lutea Lour. (1790) ; KEY TO THE SPECIES S; dmiflora Benth. seems to be a valid name ; A Calyx-ribs as many as number of;lonnal lobes S. euphrasioides (Vahl) Benth. is valid, but, as will B Sterns usually purple ; leaves reduced to be demonstrated presently, refers to a plant different scales I. g~rioiclbs from the one mentioned by Bentham ; S. thunbergiz BD Stems green ;leaves not reduced to scaIes 2. dbnn@ru Benth., based on Buchnera 6ilabiata Thunb. Prodr. AA Calyx-ribs more than the number of normal lobes F1. Cap. loo, 1794, becomes a synonym of Striga C One calyx-rib terminating at the tip bilabiata (Thunb.) 0. Kuntze, Rev. Gen. PI. 3(2): of each lobe ;the rest terminating 240, 1898. in the sinuses 3. lutsa Our second task is to show that the plant usually CC Three calyx-ribs terminating at the called S. euphrasioides Benth. has to be renamed. tip of each lobe D Flowers white ; corolla exserted 4. angwtifdia Bentham in Hook. Comp. Bot. Mag. I : 364, 1836 DD Flowers yellow ; corolla usually and in DC. Prodr. lo: 503, I 846, described a plant included 5. suIpIiurca with elongated leaves, Ion striated, sub-15-ribbea calyces and pubescent corolP ae. He cited Buchnera I. Striga psnerioides (Willd.) Vatke in Oest. Bot. euphrasioides Vahl as the basionym of his plant. Zeitschr. 25 : I I, 1875 ; Pennell in Acad. Nat. We have been able to study Vahl's type material Sc. Phil. Mon. 5: 97, 1943 ; Santapau in through hotographs kindly sent us by Dr. Skovsted Journ. Bomb. nat. Hist. Soc. 49: 42, 1950 of the gotanical Museum of the University in (S. gesnerioides). Copenhagen. Buchnera euphrasioides Vahl has Buchnera gesnerioides Willd. Sp. PI. 3: 338, short leaves, a non-elongated calyx and a villous I 800. corolla. Dr. Skovsted has examined the calyces of B, hydrabadensis Roth, Nov. P1. Sp. 292, 1821. B. euphrasioides Vahl and has found them to be B. orobanchioides R. Br. in Salt, Abyss. App. 5-ribbed. 64, 1814, nom. nud. & ex Endl. in Bot. Consequentlv, Vahl and Bentham are referring; Zeit. 2 : 388, t. 2, 1832 ; Benth. Scroph. Ind. to quite histin'ct plants even though they are usin$ 40, 1835. the same s ecific epithet euphrasioides. The name Striga orobanchioides (R. Br. ex Endl.) Benth. Striga eup Rrasioides (Vahl) Benth. must, according in Hook. Comp. Bot. Mag. I : 361, t. 19, to Art. 55 of the Code, be restricted to the plant I 836 ; Dalz. & Gibs. Bomb.' Fl. 18I, 1861 ; described by 'Vahl. Hook. f. in F1. Brit. Ind. 4: 299, 1884; The plant usually called 5. euphrasioides by Cooke, Fl. Bomb. 2 : 302, 1905 ; Van. Buren authors of Indian floristic works has to be renamed. in Poona A ric. Coll. Mag. 5 : 284, t. 3, 1914 It so happens that Buchnera asiatica Vahl is none (S. orobancIf oides) ; Gamble, F1. Madr. 967, other than the plant called S. euphrasioides Benth. 1924 ; Barnes in Journ. Ind. Bot. Soc. 15: Photographs of Vahl's type clearly show a 15-ribbed 126, f. I, 1936. calyx an'd exserted corolla. B. asiatica Vahl is var. gesnerioih. Mature stems up to 40 cm. a common plant in Western India and has to be Flower tube up to I cm ;limb more than 5 mrn transferred to the Genus Striga. However, it can- in diam. Parasitic on roots of Lepidagathis, not be called S. matica as this would be a later Euphorbia and Dysophylla spp. homonym ruled out by .Art. 64 of the Code. Type in the Willdenow Herbarium of the According to the provisions of Art. 72 we have to Botanischer Museum, Berlin-Dahlem. take up the oldest available legitimate epithet and Occurrence : Fairly common throughout use it m a new combination. This epithet is avail- Western India. able to us in Buchnera angustifolia Don, Prodr.