FRITILLARIA ATROLINEATA (LILIACEAE), A NEW SPECIES FROM IRAN

A new Fritillaria species, F. atrolineata, is described from Iran. The new species, an endemic to Western Azarbaijan, belongs to the F. caucasica group, sect. Olostyleae, subgenus Fritillaria. SEM studies of nectaries, stamen, pollen and styles are presented. Differences from other Iranian species in the Caucasica group are discussed. The chromosome number is 2« = 24.

Fritillaria atrolineata can be classified in subgenus Fritillaria, sect.Olostyleae (Boiss).Rix in ed. and more specifically in the F. caucasica group, not only because of its narrowly campanulate flowers but above all on the basis of its comparatively small overall size, and shape, position and colour of the nectaries.Fritillaria in Iran is relatively poor in species (c.15) compared with Turkey (c.30).According to Rix (1977Rix ( , 1984) ) the F. caucasica group presents many taxonomic difficulties in Turkey, on account of frequent hybridization, resulting in + intermediate specimens.In Iran, however, differences between species are more clear-cut, with fewer indications of introgression.Here, five previously described species (Rechinger, 1990) are found belonging to this complex: F. caucasica Adams, F. zagrica Stapf, F. assyriaca Baker, F. uva-vulpis Rix and F. chlorantha Hausskn.& Bornm.
Among the Iranian taxa belonging to the complex, F. atrolineata seems to be related to F. chlorantha, mainly due to the colour of its flowers.There are, however, clear-cut differences which characterize F. atrolineata as a distinct species: a comparatively long stem; glaucous, long and narrowly oblanceolate leaves with the lowest ones sometimes two or three in subopposite or subverticillate (subternate) position; small, narrowly campanulate flowers; dark, elongate linear nectaries, and entire styles.By contrast, F. chlorantha has short stems; short, wide, shiny green leaves, all alternate; comparatively big tubular flowers; green, lanceolate nectaries, and styles trifid at apex.
F. assyriaca is distinguished from F. atrolineata by the presence of 3-12 small bulbils at the base of the bulb at flowering time; papillose stem; linear, canaliculate leaves; purplish-brown anthers; green, elliptic-oblong nectaries.As for F. uva-vulpis which was described as a new species in the F. caucasica group by Rix (1974), the presence of four widely spaced, green, lanceolate leaves; rounded flowers and wide, ovate nectaries separates that species from F. atrolineata.
In F. zagrica, the stems are comparatively short, and the tepals are dark purplishbrown with a bright yellow apex, whereas in F. atrolineata, stems are taller and flowers are bright green without any dark bloom.
F. caucasica, finally, differs in phyllotaxy (leaves are all alternate), flower colour, which is purplish in F. caucasica but green in F. atrolineata, nectary colour and shape (green, lanceolate versus black, linear), and vestiture of filaments and styles.These are smooth or only sparsely papillose in F. caucasica in contrast to the densely papillose clothing in F. atrolineata.
A key to the Iranian species of the F. caucasica group is included in Bakhshi Khaniki(1997).
Among non-Iranian species, some forms of F. pinardii are superficially similar to F. atrolineata on account of flower shape but differ in stem pubescence (sometimes papillose), phyllotaxy (leaves all alternate, shorter and wider), nectary colour and shape (green versus black, linear-lanceolate versus long-linear), general appearance of pollen grain and exine sculpturing.

SEM STUDIES OF NECTARY, STAMEN, POLLEN GRAIN AND STYLE
As mentioned earlier, the elongate linear nectary of a black colour against a green background is one of the most important characters in F. atrolineata.A scanning electron microscopy (SEM) study shows that the nectaries are placed at the base of the perianth segments (Fig. 3A, B) and that the cells of the nectaries are smaller and narrower, and more rectangular, than those of the nectary borders and tepal surface (Fig. 3C, D), probably reflecting their role in nectar sugar secretion.
The attachment of anther to filament has been used for sectional characterization but further investigations on this are needed.There are generally two kinds of attachment, basifixed and dorsifixed.In F. atrolineata attachment is basal (Fig. 3E).Another androecial character of doubtful value, which has been used by taxonomists, is the presence or absence of papillae on the filaments.In F. atrolineata, filaments are densely papillose in the upper part and glabrous at the base (Fig. 3E, F).The shape and size of the anthers also have some importance but a word of warning must be given here.The anthers change very much with age and especially after dehiscence.Many published anther characters are useless or misleading because the author has not stated whether indehisced or dehisced anthers were studied.In F. atrolineata the indehisced anther is ellipsoid.
Pollen grains in F. atrolineata are monocolpate (monosulcate) (Fig. 5A).The general shape of the pollen grains in this species is ellipsoid.Exine seems to be rough (not smooth) due to very small granulae.It is foveolate with bigger and smaller luminae.The biggest holes are mainly concentrated laterally (Fig. 5B).The pollen grains are sometimes covered by pollen-kitt.The pollen shape and exine structure in F. atrolineata are rather close to that of F. caucasica but differ from other taxa in the F. caucasica group in general appearance, exine sculpture (presence or absence of knobs) and size of luminae.Generally, pollen is monosulcate in the genus Fritillaria (Radulescu, 1973), as elsewhere in the Liliaceae, but exine sculpturing is rather variable (pers.obs.).
The style is stout, and densely papillate (Fig. 4A, B).The entire or subentire style in F. atrolineata (Fig. 4C) separates it from some other species with trifid styles in the F. caucasica group (i.e.F. chlorantha, F. zagrica, F. assyriaca, F. armena, F. minuta, etc.).Species with the style clearly trifid form sect. Trichostyleae, while the others, with the style undivided or only a little trilobulate at the apex, form sect. Olostyleae.The distinction is generally clear enough, but sometimes there may be difficulties in deciding whether a style is shortly trifid or rather shortly lobulate.The validity of the style feature seems questionable, and according to Turrill & Sealy (1980), it would be worth considering whether there are not some species with a trifid style more closely related to species with a lobulate or undivided style than to those with which they have been associated.It seems that the end of the lobes are

PHYTOGEOGRAPHY
F. atrolineata has been collected from only one locality, Shohada (Ghasemlu) valley, in Western Azarbaijan (Fig. 7).Different parts of this province and neighbouring provinces (Eastern Azarbaijan, Kordestan, Ardabil) have been visited but the species was not observed anywhere else.It occurs in rock crevices and in moist areas below cliffs at an altitude of 1500-1800m.It is found at the base of the valley.The altitude of the mountains around the valley reaches 2500-3000m and they may serve as a barrier to dispersion.Such places are favourable for endemism and it certainly seems so far that F. atrolineata is an endemic species for the area in question.
Fritillaria species, F. atrolineata, is described from Iran.The new species, an endemic to Western Azarbaijan, belongs to the F. caucasica group, sect.Olostyleae, subgenus Fritillaria.SEM studies of nectaries, stamen, pollen and styles are presented.Differences from other Iranian species in the Caucasica group are discussed.The chromosome number is 2« = 24.