Nomenclatural and taxonomic notes on Jacobaea borysthenica ( Asteraceae ) and some related taxa

and notes on Jacobaea borysthenica ( Asteraceae ) and some related taxa. Abstract . Following our recent lectotypification (with a specimen from G-DC) of the name Senecio praealtus Bertol. var. borysthenicus DC. validated by de Candolle based on Andrzejowski's and Besser's specimens from Ukraine, we provide here information on additional original specimens of that taxon (KW: Besser and Turczaninow historical collections), which is now recognized as Jacobaea borysthenica (DC.) B.Nord. & Greuter and which was until recently widely accepted as Senecio borysthenicus (DC.) Andrz. ex Czern. ( Asteraceae ). In particular, there are two isolectotypes in KW collected by Andrzejowski near Kyslyakivka (now Lymany, Mykolayiv Region, Ukraine), as well as some other specimens collected near Zaporizhzhya (Andrzejowski) and in southern Podolia (Besser and/or Andrzejowski). Some related Eastern European taxa of the taxonomically complicated Jacobaea vulgaris Gaertn. (= Senecio jacobaea L.) aggregate and misapplied names are discussed as well. The identity of the name Senecio divaricatus Andrz. ( nom. illeg ., non L.) is clarified; it is a synonym of Jacobaea borysthenica . It is also confirmed that Senecio podolianus Panigrahi is an illegitimate replacement name for S. borysthenicus . Jacobaea borysthenica seems to be closely related to J. andrzejowskyi (Tzvelev) B.Nord. & Greuter and J. vulgaris subsp. pannonica Hod á lov á & Mered'a; the two latter taxa morphologically differ from J. borysthenica but are very similar to each other and may be even conspecific. Further studies are needed for clarifying the complex evolutionary and biogeographical patterns within the J. vulgaris aggregate in Eastern Europe and adjacent areas.


Introduction
The present nomenclatural and taxonomic contribution is a continuation of our earlier publications on East European taxa of the species aggregate of Jacobaea vulgaris Gaertn. (= Senecio jacobaea L.) (see Mosyakin, Yena, 2017;Mosyakin, 2018Mosyakin, dated "2017Mosyakin et al., 2019). In particular, in our recent article (Mosyakin et al., 2019) we designated the lectotype for Senecio praealtus Bertol. var. borysthenicus DC., the basionym of the currently accepted name Jacobaea borysthenica (DC.) B. Nord. & Greuter, but some nomenclatural and taxonomic details and considerations on that species remained beyond the scope of our short nomenclatural note. These additional details and considerations are provided below.
Judging from available evidence, Jacobaea borysthenica occurs in southern regions of Eastern Europe, mainly in sandy steppe and alluvial habitats along river valleys in southern and central regions of Ukraine and adjacent areas of the southwestern European part of Russia (Schischkin, 1961;Minderova, 1962;Tzvelev, 1986;Konechnaya, 1994;Katina, 1987;Kucherevs'kiy, 2004;Tarasov, 2012). This species is also reported from Romania (Popescu, 1972(Popescu, , 1973Ciocârlan, 2009Ciocârlan, , 2011Doroftei et al., 2011;Negrean, 2011) and Belarus (Parfenov et al., 1987;Tretyakov, 1999). In our opinion, Belarusian records need confirmation. At least, we have not seen any reliable specimens of J. borysthenica from Belarus. In addition to confirmed records from Ukraine, Romania, and Russia, the species most probably also occurs in Moldova because it is reliably recorded in the nearby territories in Ukraine; however, it is not reported in Geideman (1986 and earlier editions).
Jacobaea borysthenica is listed (as Senecio borysthenicus) as a regionally protected species in Dnipropetrovsk (Dnipro), Donetsk, Luhansk (Lugansk), and Odesa (Odessa) administrative regions (oblas'ts) of Ukraine (Andrienko, Peregrym, 2012) and is considered a rare and threatened plant in Romania (Făgăraş et al., 2010). It was included in the second edition of the Red Data Book of the Republic of Belarus (Darafeev et al., 1993; see also Parfenov et al., 1987), but is not listed anymore in the third edition (Horuzhyk et al., 2005) because the species was re-considered as an alien in Belarus.
The herbarium acronyms here and below are given following Index Herbariorum (Thiers, 2008-onward).
Blue labels with typographically printed words "Herb. W. Besser" mounted on the three mentioned specimens are printed on the blue paper that seems to be identical to the paper used for publication of the first edition of Besser's Catalogue (Besser, 1810)] The three syntypes cited above and specifically the lectotype (G00471753) are discussed in our lectotypification note (Mosyakin et al., 2019). However, several other original specimens collected and annotated as Senecio borysthenicus by Besser and/or Andrzejowski are currently deposited in the Besser and Turczaninow historical collections in the National Herbarium of Ukraine (KW, Herbarium of the M.G. Kholodny Institute of Botany, National Academy of Sciences of Ukraine, Kyiv); these specimens deserve additional discussion, which is provided below.

Specimens in the Turczaninow herbarium (KW-TURCZ).
One specimen from the Turczaninow herbarium has the characteristic blue label of Besser: "Senecio borysthenicus Andrzej. Circa Kislakowka, Gub. Cherson. Herb. W. Besser" (KW001002876, Fig. 1). The village of Kyslyakivka (now Lymany in Vitovs'ky District of Mykolayiv Region, southern Ukraine) was located on the shore of the Southern Bug Estuary (Бузький лиман in Ukrainian) near its confluence with the Dnipro (Dnieper) Estuary (Дніпровський лиман in Ukrainian), in the former Kherson Governorate. It was mentioned as"Kiślakówka" by Andrzejowski in Chapter 2 "Kraina wapienna i nadmorska" ("The limestone and seashore land") of his Rys botaniczny... (Andrzejowski, 1823: 23). Another specimen in the same folder has the white label  Both plants (KW001002876 and KW001002877) taxonomically belong to Jacobaea borysthenica, and the first specimen can be regarded as an isolectotype.
The same folder contained two additional specimens collected by Czerniaëw (also variously transliterated as Chernyaev, Tschernaiew, Czerniaiev, or Czernajew) in the eastern part of Ukraine (KW001002878: "Starobielsk et Charcow" -now Starobil'sk in Luhansk Region, and Kharkiv in Kharkiv Region, Ukraine) and in an adjacent part of Russia on the Don River (KW001002879: "ad Tanain"). However, these poorly preserved specimens do not belong to the original material of S. praealtus var. borysthenicus. Moreover, morphologically they differ from Jacobaea borysthenica and belong to J. vulgaris sensu lato. The sheet KW001002878 contains four plant fragments: two of them are evidently parts of the same plant (probably collected in or near Kharkiv? identifiable as J. vulgaris) and the other two (upper parts with inflorescences, mounted on the left side of the sheet, probably collected in Starobil'sk?) are morphologically different from the right-side plant. It looks like there are two collections with one label, and some plant fragments (collected in Starobil'sk?) may in fact belong to the taxon now known as J. andrzejowskyi (Tzvelev) B. Nord. & Greuter (in Greuter, Raab-Straube, 2006: 712). Despite the partial misapplication of the name Senecio borysthenicus, Czerniaëw validly published the species-rank combination (see above).

Specimens in the Besser herbarium (KW-BESS).
The original folder annotated as "Sen. Jacobaea β Borysthenicus" in the Besser herbarium (KW) contained 12 unmounted specimens and plant fragments collected in Ukraine (the Dnieper cataracts near the present-day Zaporizhzhya, "Tauria", "Podolia", etc.), most of which indeed belong to J. borysthenica. However, at least two specimens are identifiable as J. erucifolia (L.) G.Gaertn., B.Mey. & Scherb. sensu lato (incl. J. grandidentata (Ledeb.) Vasjukov), which probably reflects the uncertainly in Besser's understanding of the identity of these taxa; these plants were collected in "Tauria" (most probably Crimea) and in "Cherson" or "Podolia" (two labels in one specimen, one label was probably misplaced). Additional information is provided below on selected specimens with original informative labels and original annotations. The specimen KW001002880 (Fig. 2) from the Besser herbarium was collected in the same locality as the lectotype of Senecio praealtus var. borysthenicus (formerly Kyslyakivka, now Lymany) and can be regarded as an isolectotype. Its label also contains a brief description by Andrzejowski: "involucr. ovatis enerviis ciliatis apice subsphacelatis, bracteis copiosis, linearilanceolatis elongatis. ad Hyp. infer. prope Kislakowka".
Thus the Turczaninow and Besser historical collections at KW contain several original specimens, including two isolectotypes (KW001002876 and KW001002880, Fig. 1 and Fig. 2, respectively) collected by Andrzejowski in or near Lymany village (formerly Kyslyakivka, Kherson Governorate) in Vitovs'ky District of Mykolayiv Region. These specimens from KW, in addition to the three specimens from the de Candolle Herbarium (G-DC, see Catalogue des herbiers de Genève (CHG), 2019-onward; Mosyakin et al., 2019), provide sufficient information for establishing the precise morphology-based identity of Jacobaea borysthenica.

Andrzejowski's treatment of Senecio in 1862
In his Continuatio Enumerationis Plantarum… Andrzejowski (1862: 103) listed the taxa of Senecio (sensu lato) occurring in the former Podolian Governorate and adjacent areas. Since that publication is rare and not available online, we provide here the text fragment from that treatment relevant to the taxa discussed in our article.
"3. Jacobaea L. vulgaris, Julio. We were unable to find any original specimens annotated as Senecio divaricatus Andrz. in the Besser memorial herbarium (where most of Andrzejowski's specimens are deposited) or in any other collection at KW. However, the description and geographical information provided by Andrzejowski leaves no doubt that this name is applicable to the taxon originally described as Senecio praealtus var. borysthenicus and now accepted as Jacobaea borysthenica. Andrzejowski's record of Senecio jacobaea var. borysthenicus from Kyiv (Kiev) is somewhat enigmatic because typical plants of Jacobaea borysthenica are unknown in the Kyiv area. Most probably that record in fact refers to alluvial plants of the J. vulgaris aggregate identical to or approaching J. andrzejowskyi, or to some other taxon of that species complex.
It is not clear why Andrzejowski decided to change the original circumscription of his Senecio borysthenicus, as initially outlined and annotated in the Besser and de Candolle herbaria. In any case, it is nomenclaturally irrelevant because the name S. divaricatus Andrz. is illegitimate, being a later homonym of S. divaricatus L. (Linnaeus, 1753: 866).

The status of Senecio podolianus Panigrahi
There were two different versions of English translations published for several volumes of the Flora of the USSR (see Schmid, 1998, who described that as a "bibliographically Kafkaesque situation"). In his editorial note to the treatment of Senecio in the "Indian" version (which seems to be rarer in libraries than the "US version", and is not available online) of the English translation of Vol. 26, the scientific editor of that volume Panigrahi (1995: 822) introduced the name S. podolianus Panigrahi with the following justification, reproduced here in toto and verbatim: "It is not clear as to why S. borysthenicus Andrz. ex DC. (1837), 'nom. in syn.' is treated as the correct name for this species, nor it is indicated where S. borysthenicus Andrz. was "already done", as stated under the "Note" above. The place of publication of Steven's observation is also not given. If S. praealtus β borysthenicus DC. (1837)  The evidently illegitimate replacement name S. podolianus proposed by Panigrahi resulted from his insufficient acquaintance with botanical literature on the subject and misinterpretation of the rules of nomenclature. Grossheim (1949: 470) did not describe a new species but just cited the name "S. borysthenicus Andrz." that he misapplied to the Caucasian plants that were later described as S. schischkinianus Sofieva (1957: 83) Greuter (in Greuter, Raab-Straube, 2006: 713)]; the latter species was also recently reported from Kalmykia (Sagalaev et al., 2012). However, as we noted above, before Grossheim the binomial Senecio borysthenicus was validated earlier (Czerniaëw, 1859) and used by several other authors (e. g., Gruner, 1869Gruner, dated "1868Taliev, 1935;Stankov, Taliev, 1949, etc.). Type: not designated; described from several localities in southern Ukraine (see above).

Some names misapplied to Jacobaea borysthenica in the past, remaining taxonomic problems, and concluding remarks
The name "Senecio armenius" was sometimes misapplied to Jacobaea borysthenica. That invalid name was mentioned by Ledebour (1845: 634)  At least some earlier literature records of Senecio borysthenicus (especially from northern and eastern parts of its range) may in fact refer to Jacobaea andrzejowskyi or similar forms. When describing Senecio andrzejowskyi Tzvelev (now accepted as a species of Jacobaea), Tzvelev (1986: 254-255) mentioned that it seems to be morphologically intermediate between S. jacobaea and S. borysthenicus, and further hypothesized that his new species might be of ancient hybrid origin, resulting from introgressive hybridization of northern populations of the psammophytic species S. borysthenicus with the meadow-steppe S. jacobaea sensu stricto.
High-resolution scanned images of the holotype (LE01053112) and isotype (LE01053113) of S. andrzejowskyi were kindly provided by Ivan V. Tatanov and Irina V. Sokolova (LE, see below). Judging from these images, Jacobaea andrzejowskyi is morphologically quite close to (or even identical with?) the octoploid forms of the J. vulgaris aggregate recently described as J. vulgaris subsp. pannonica Hodálová & Mered'a [see Hodálová et al., 2015(online before print Nov. 2014): 1538. Both these taxa, however, evidently differ in their morphology from J. borysthenica, which should be regarded as a rather well delimited species, both morphologically and ecologically.
Rather large populations of the plants morphologically corresponding to Jacobaea vulgaris subsp. pannonica were observed and collected by Sergei Mosyakin in 2017 and 2018 in meadow and meadow-steppe habitats on slopes of the valley of the Hnylyi Tikych River, and on nearby slopes of hills and ravines near the village of Snizhky, Stavyshche District, Kyiv Region, close to the border with Cherkasy Region. At present it is the easternmost known locality of that taxon, in Ukraine and in general. However, it is quite possible that this taxon is much more widespread in Eastern Europe than it has been expected before. Its relationships with other taxa of the J. vulgaris aggregate from Eastern Europe (reported as taxa of Senecio sensu lato: see Tzvelev 1986;Konechnaya, 1994, etc.), such as J. andrzejowskyi (see above) and J. ferganensis (Schischk.) B. Nord. & Greuter (Senecio ferganensis Schischk.), remain insufficiently known. Comprehensive studies of the whole species aggregate of J. vulgaris and related taxa in Eurasia (and especially in Eastern Europe) may bring new important results complementing the studies of this plant group in Western and Central Europe (e.g., Wysk et al., 2009;Hodálova et al., 2010Hodálova et al., , 2015Mered'a et al., 2016). Figure 2E. A specimen of "Senecio borysthenicus Nob." from the Turczaninow herbarium in KW, collected by Andrzejowski in or near the present-day city of Zaporizhzhya, KW001002882. e3 Figure 3E. A specimen labeled as "Sen. praealtus β Borysthenicus" from the Besser herbarium in KW, collected by Andrzejowski near cataracts of the Dnipro in or near the present-day city of Zaporizhzhya, sheet 1 (KW001002881). e4 Figure 4E. The same specimen as in Fig. 3E, sheet 2 (KW001002883).