Annual or perennial plants with fibrous, partly fibrous, partly fleshy or more or less tuberiform roots. Leaves basal and cauline, entire in some species, more often palmatifid or palmatipartite, lobate or rarely pinnate. Flowers solitary or in a cymose inflorescence. Sepals usually 5, deciduous after flowering. Petals 5, rarely more or less, with a subbasal nectar-pit often protected by a scale. Stamens numerous, spirally arranged. Carpels arranged in globose to oblong heads, unilocular with one ovule. Fruitlets (achenes) nut-l ike, inflated or ± laterally compressed, usually with a distinct, straight or curved style (beak).
The number of species indicated varies greatly from author to author (about 600 according to Ovezinnikov in Fl. URSS., 400 in J.C. Willis. A Dictionary of the Flowering Plants & Ferns ed. 8, Cambridge. 1973). The genus has not been treated monographically after De Candolle's Prodromus (1824), so that it is very. difficult to get a general idea of its natural limits and its evolution in time and space. It is cosmopolitan from arctic tundras to subtropical deserts and tropical mountain ranges occurring in all kinds of different habitats, though very few species are adapted to arid conditions.
Many groups of species are taxonomically critical, and most of them have been treated only locally if at all, with nearly no attempts to correlate results from various countries. In Pakistan, especially Ranunculus hirtellus Royle and its relatives deserve much closer examination of rich herbarium as well as living material. It is difficult to delimit the species in this group as in the related European groups around Ranunculus auricomius L. and Ranunculus montanus Willd. The present account is provisional, but an attempt has been made by showing the underlying difficulties and by proposing possible solutions.
Many Ranunculus species are poisonous. Some species have been introduced as weeds in many parts of the world. Represented in Pakistan by 23-25 spp.
Species not seen
Ranunculus brotherusii Freyn. in Bull. Herb. Boiss. 6:885. 1878, Ovez. in Komarov, Fl. URSS 7:392. 1937, Stewart, Ann. Catalogue Vasc. Pl. W. Pak. & Kashm. 270. 1972, Qureshi & Chaudhri, l.c. 165.
Ranunculus affnis auct. non L.: Hookf. & Thoms. in Hook.f., Fl. Brit. Ind. 1:18. 1872, Ranunculus pedatifdus Ledeb., Fl. Ross. 1:732. 1842 non L., Ranunculus caespatosus Wall. Catalogue no. 4701, non Thuill. 1800.
A perennial up to 25 cm tall with thin fibrous and thickened cylindrical roots. Flowers 8-18 mm broad, yellow. Leaf segments 1-2 mm broad, sessile or lateral segments pedately arranged.
Type: Turkestan, Kokbulak, at the springs of the river Noryn, V.F. Brotherus 818.
Distribution: Kashmir, Tien Shan.
Reportedly collected by T. Thomson from Nubra in Baltistan (fide Stewart, Ann. Catalogue Vasc. Pl. W. Pak. & Kashm. 270. 1972). Said to be common between 3300-5200 m.
Ranunculus paucidentatus Schrenk in Bull. Phy. -Math. Acad. Petersb. 3:309. 1845, Over. in Komarov, Fl. URSS. 7:49. 1937, Stewart, Ann. Catalogue Vasc. Pl. W. Pak. & Kashm. 272. 1972, Qureshi & Chaudhri, l.c. 159.
A species resembling Ranunculus aucheri, but differing mainly in the plant parts with spreading hairs, the leaves which are not lobed but 3-dentate at the apex. Flowers yellowish-green.
Type: Described from the Alatau mountains (LE).
Distribution: C. Asia,? Northern Pakistan.
R.R. Stewart (l.c.) mentions three gatherings from Chitral and Swat which I have not seen.
Ranunculus aucheri Boiss. in Ann. Sci. Nat. Ser. 2, 16: 351. 1841, R.R. Stewart, l.c. 269, Qureshi & Chaudhri, l.c. 159.
A species closely resembling Ranunculus afkhanicus but differing in the narrow leaf s egments and hairs that are appressed (not spreading).
Type: Iran: Isfahan, Aucher 4006 (G).
Distribution: W. Iran to N.W. Pakistan.
R.R. Stewart (l.c.) mentions two gatherings from Chitral, which I have not seen.
Ranunculus kohistanensis Qureshi & Chaudhri, Pak. Syst. 3(1):16.1987, 4 (1,2):172. 1988.
According to the authors the species is characterised by the few-flowered (1-2) inflorescence, glabrous receptacle, wrinkled pubescent achenes, oblong leaf segments and annual habit.
Type: Muzaffarabad: Gujar Nar, c. 3500 m, Shohzad Oat & A. Abbasi1941 (ISL).
Distribution: N. W. Pakistan, Kashmir.
The species is said to be related to Ranunculus hirtellus and Ranunculus brotherusii According to the authors (op.cit) it differs from the former in the glabrous receptacle, wrinkled achenes and 1-2-flowers per inflorescence. From the latter it differs by the annual habit, the leaf segments which are oblong and deciduous sepals.
Ranunculus waziristanicus Qureshi & Chaudhri in Pak. Syst. 4, (1-2) A58. 1988.
Ranunculus nanus sensu Blaster in J. And. Bet. Soc. 9:199. 1930: R.R. Stewart, Ann. Catalogue Vasc. Pl. W. Pak. & Kashm. 274. 1972, non Fisch. ex DC. 1824, nec W. J. Hooker, 1834.
This species is characterised by its caespitose habit and rugose leaves which are scaly on both surfaces. I have not seen the type specimen (N. Waziristan: Razani, c. 1600 m, April 1927, Fernandez 2734, BLAT), to comment on the nature of affinity of the above species.