New species of the genus Taraxacum (Asteraceae, Cichorieae) from Croatia III

Abstract: Taraxacum annetteae and Taraxacum croaticum, found in the N coastal part of Croatia, are described as species new to science and illustrated, and their known distributions are given. Both species belong to T. sect. Erythrosperma. Citation: Uhlemann I. 2016: New species of the genus Taraxacum (Asteraceae, Cichorieae) from Croatia III. — Willdenowia 46: 225–232. doi: http://dx.doi.org/10.3372/wi.46.46203 Version of record first published online on 28 July 2016 ahead of inclusion in August 2016 issue.

Distribution -Taraxacum annetteae is an extremely rare species. Up to now it is known only from two remote localities in Croatia, where it forms populations with more than 100 individuals (Fig. 7).
Affinities -The most striking diagnostic feature of Taraxacum annetteae is the intense purple coloration (even in shady places) of the arcuate-reflexed outer bracts with their tips pointing back to the scape. Each of these outer bract character states (colour and position) is rare in T. sect. Erythrosperma, but the combination is unique.
Furthermore, the species is characterized by light purple petioles, shortly triangular, blunt or sometimes lingulate lateral leaf lobes with a distinct large tooth on the distal margin and a less distinct tooth on the proximal margin, tar-coloured interlobes, pollen-producing anthers, dark greyish green styles and small, pale brown achenes with large spines in the distal part.
With regard to the arcuate-reflexed outer bract position, Taraxacum annetteae resembles T. lacistophylloides Dahlst. (1933), but the latter species has light green outer bracts, a more robust habit, grey achenes and a completely deviating shape of lateral leaf lobes.
In T. purpureocornutum Soest (1957), a rare and probably endemic species from Corsica (Štěpánek & Kirschner 2012), only the outermost outer bracts are arcuate-reflexed, whereas the inner ones are arcuate or patent. Moreover, this species has a completely deviating leaf shape, pinkish grey-green outer bracts, produces no pollen and has larger achenes with a longer pyramid than T. annetteae.
Only a few other species of Taraxacum sect. Erythro sperma have intensely purple-coloured outer bracts, such as T. pupureomarginatum Soest (1964), but this species differs from T. annetteae in having irregularly arcuate outer bracts, yellow-green styles and larger, grey achenes. Also the C and N European T. bellicum Sonck (1983) has an intense purple outer bract coloration, but in contrast red-brown achenes c. 3 mm long with a cone 1.3 -1.5 mm long, triangular, acuminate lateral leaf lobes and a long sagittate, incised terminal leaf lobe.
With regard to leaf shape, Taraxacum lingulilobum Sonck (1984), described from Greece and also found in Bulgaria (Štěpánek & Kirschner 2014), is similar, but this species has green or very faintly dirty violet petioles, dark green outer bracts and red-brown achenes more than 3 mm long with a cone c. 1 mm long.
The pale brown achenes of Taraxacum annetteae resemble those of T. plumbeum Dahlst (1911) with respect to their coloration, but the latter species has a completely deviating leaf shape and green, erect outer bracts with recurved tips.  Uhlemann: New species of Taraxacum from Croatia III Eponymy -The epithet is dedicated to my wife, Annette, who has patiently supported and suffered my taxonomic studies in Taraxacum over a period of more than two decades.
Distribution -Taraxacum croaticum is so far known from Istria and the islands of Cres, Losinj, Pag and Rab in the bay of Kvarner in Croatia, and from a single, remote locality in Starigrad, Dalmatia (Fig. 7).
Affinities -Taraxacum croaticum is mainly recognized by its flowers lacking pollen, greyish to blackish styles, pale brown achenes, few erect outer bracts, thin, unwinged and purple-red petioles, a characteristic leaflobation with more or less entire and hamate lateral lobes and long interlobes.
With regard to leaf shape this species is related to other species in Taraxacum sect. Erythrosperma with more or less hamate lateral lobes, such as T. lambinonii Soest (1961), which is distinguished by strongly hamate leaf lobes, shorter interlobes, presence of pollen and (greyish)brown achenes; and furthermore T. aquitanum Hofstra (1988), with strongly hamate leaf lobes, shorter interlobes, presence of pollen, erect to patent outer bracts and red-brown achenes with a shorter, 0.7 -0.8 mm long cone.
Taraxacum croaticum should be also compared with the well-known species T. parnassicum Dahlst. (1926) [= T. silesiacum Dahlst. ex G. E. Haglund (1938) = T. praegracilens Sonck (1989), nom. nov. for T. pseudo gracilens Sonck (1988)], common in C Europe, ranging to the Mediterranean and scattered in N Croatia, which resembles the first in its flowers lacking pollen, dark styles and more or less hamate to recurved lateral lobes on the outer leaves. Some modifications of T. par nassicum, for instance those pictured under the name T. pseudogracilens (Sonck 1988: 77, fig. 3A, C), tend with regard to leaf shape to T. croaticum; but, in contrast, T. parnassicum has more numerous outer bracts, which are patent or erect with recurved tips and a deviating leaf lobation (shorter and patent lateral lobes on the inner leaves, which tend to stand closer in the distal part of the leaf, and short interlobes).
Taraxacum croaticum also resembles to T. plumbeum Dahlst (1911) with regard to the pale brown achenes and leaf lobation, but the latter species has aranose leaves, short, hamate to recurved lateral leaf lobes, which sometimes (mainly on the inner leaves) become long and tapering, shorter interlobes and pollen-producing anthers.
Superficially considered, Taraxacum croaticum is similar to some modifications of T. erythrospermum