[2.13.6] Viola sect. Plagiostigma subsect. Patellares 

Viola subsect. Patellares (Boiss.) Rouy & Foucaud, Fl. France [Rouy & Foucaud] 3: 35. 1896 

≡ Viola [sect. Nomimium; unranked] §.3. Patellares Boiss., Fl. Orient. 1: 451. 1867, p.p. (excl. Viola uliginosa).—Lectotype (designated here): Viola kamtschatica Ging. (=V. selkirkii Pursh ex Goldie)

=Viola [sect. Nomimium; unranked] b. Patellariae Nyman, Consp. Fl. Eur. 1: 79. 1878, p.p.—Lectotype (designated here): Viola umbrosa Fr. (=Viola selkirkii Pursh ex Goldie)

=Viola subg. Violidium K. Koch in Linnaea 15: 251. 1841. ≡ Viola sect. Violidium (K. Koch) Juz. in Schischk. & Bobrov, Flora URSS 15: 408. 1949 

≡ Viola subsect. Violidium (K. Koch) P. Y. Fu in Fl. Pl. Herb. Chin. Bor.-Or. 6: 93. 1977.—Type: Viola somchetica K. Koch

=Viola [unranked] (“Gruppe”) Estolonosae Kupffer in Oesterr. Bot. Z. 53: 329. 1903 

≡ Viola subsect. Estolonosae (Kupffer) Kupffer in Kusnezow et al., Fl. Caucas. Crit. 3(9): 217. 1909 

≡ Viola sect. Estolonosae (Kupffer) Vl. V. Nikitin in Bot. Zhurn. (Moscow & Leningrad) 83(3): 132. 1998.—Lectotype (Nikitin 1998 [72], page 133): Viola purpurea Stev. (=V. somchetica K. Koch)

=Viola [sect. Nomimium; unranked] Adnatae W. Becker in Nat. Pflanzenfam., ed. 2 [Engler & Prantl], 21: 368. 1925 

≡ Viola subsect. Adnatae (W. Becker) W. Becker in Acta Horti Gothob. 2: 285. 1926

 ≡ Viola ser. Adnatae (W. Becker) Steenis in Bull. Jard. Bot. Buitenzorg, ser. 3, 13 (1933–1936): 258. 1934 

≡ Viola sect. Adnatae (W. Becker) Ching J. Wang, Fl. Reipubl. Popularis Sin. 51: 41. 1991; (W. Becker) Vl. V. Nikitin in Bot. Zhurn. (Moscow & Leningrad) 83(3): 132. 1998 (isonym); (W. Becker) Vl. V. Nikitin in Novosti Sist. Vyssh. Rast. 31: 222. 1998 (isonym).—Lectotype (Nikitin 1998 [72], page 132): Viola selkirkii Pursh ex Goldie

=Viola [unranked] “Gruppe” Pinnatae W. Becker, Beih. Bot. Centralbl., Abt. 2. 40(2): 119. 1924 ≡ Viola sect. Pinnatae (W. Becker) Ching J. Wang, Fl. Reipubl. Popularis Sin. 51: 76. 1991 ≡ Viola subsect. Pinnatae (W. Becker) Vl. V. Nikitin, Novosti Sist. Vyssh. Rast. 34: 125. 2002.—Type (Shenzhen Code Art. 10.8): Viola pinnata L.

=Viola sect. Brachycerae Espeut in Botanica Pacifica 9(1): 32. 2020.—Type: Viola brachyceras Turcz.

Description.—Rhizome perennial; bulbils absent. Lateral stems absent. Stipules adnate in the lower 1/3 to 3/4, pale, greenish, or purple-brown, linear to ovate-lanceolate, acute or acuminate, entire or remotely denticulate-fimbriate. Lamina lanceolate to orbicular or triangular, sometimes 3–5-sect, base cuneate to deeply cordate, sometimes decurrent, apex obtuse to acuminate, margin subentire, crenulate, dentate, or deeply incised. Corolla white to deep violet. Sepals lanceolate to ovate; appendages short to very long (0.4–6 mm), rounded to 2–3-dentate. Lateral petals usually bearded; bottom petal usually longer than the other petals ((5–)10–23(–25) mm), apex rounded to emarginate; spur long (3–10 mm) and slender, rarely short (1–2 mm) and saccate. Style at apex margined and flattened, not bilobate.

Diagnostic characters.—All stems rhizomatous AND stipules 1/3 adnate to petiole AND spur slender, up to 10 mm AND cleistogamous flowers produced.

Ploidy and accepted chromosome counts.—4x, 8x, 12x; 2n = 22, 24, 48, 72.

Age.—Crown node age c. 8.3 Ma (Figure 6), stem node age 16.6 (15.4–17.0) Ma [28].

Included species.—62. 

Viola alaica Vved., V. albida Palib., V. alexandrowiana (W. Becker) Juz., V. alexejana Kamelin & Junussov, V. bambusetorum Hand.-Mazz., V. baoshanensis W. S. Shu, W. Liu & C. Y. Lan, V. belophylla Boissieu, V. betonicifolia Sm., V. bhutanica H. Hara, V. boissieuana Makino, V. breviflora Jungsim Lee & M. Kim, V. cuspidifolia W. Becker, V. dactyloides Schult., V. forrestiana W. Becker, V. gmeliniana Schult., V. hancockii W. Becker, V. hirtipes S. Moore, V. inconspicua Blume, V. ingolensis Elisafenko, V. iwagawae Makino, V. japonica Langsd. ex Ging., V. jooi Janka, V. keiskei Miq., V. lactiflora Nakai, V. macroceras Bunge, V. magnifica C. J. Wang & X. D. Wang, V. mandshurica W. Becker, V. maximowicziana Makino, V. miaolingensis Y. S. Chen, V. microcentra W. Becker, V. mongolica Franch., V. multifida Willd. ex Schult., V. nujiangensis Y. S. Chen & X. H. Jin, V. pacifica Juz., V. patrinii Ging., V. pekinensis (Regel) W. Becker, V. perpusilla Boissieu, V. phalacrocarpa Maxim., V. philippica Cav., V. pinnata L., V. prionantha Bunge, V. rupicola Elmer, V. selkirkii Pursh ex Goldie, V. senzanensis Hayata, V. seoulensis Nakai, V. sieboldii Maxim., V. somchetica K. Koch, V. sphaerocarpa W. Becker, V. tashiroi Makino, V. tenuicornis W. Becker, V. tienschiensis W. Becker, V. tokaiensis Sugim., nom. nud., V. tokubuchiana Makino, V. trichopetala C. C. Chang, V. turkestanica Regel & Schmalh., V. ulleungdoensis M. Kim & J. Lee, V. umphangensis S. Nansai, Srisanga & Suwanph., V. variegata Fisch. ex Link, V. violacea Makino, V. yezoensis Maxim., V. yunnanfuensis W. Becker, V. yuzufeliensis A. P. Khokhr.

Distribution.— North-temperate, with a diversity centre in northeastern Asia; only four species in Europe and one in North America, the scattered circumboreal V. selkirkii.

Discussion.— Section Plagiostigma subsect. Patellares is species-rich and easily characterised by the absence of stolons, and stipules adnate to the petiole in the lower third. The corolla can be of a deep lilac tone, sometimes fragrant but with a fragrance somewhat different from that of sect. Viola (e.g., V. odorata), and the spur of the bottom petal is usually relatively longer than in the other subsections of Plagiostigma. The lamina shape is extremely variable, from spathulate to cordate in outline, and with margins subentire to crenate or variously deeply divided. Some species form adventitious shoots from roots and have the ability to regenerate from cut roots (e.g., V. prionantha). Many species of the subsection have seeds that germinate directly without stratification. Phylogenetic relationships within subsect. Patellares are contradictory. There is poor correspondence in patterns obtained from ITS sequences, cpDNA sequences, and morphology [77], but also among studies [82,86,87,89]. This may on one side indicate the presence of real genealogical conflicts resulting from incomplete lineage sorting, allopolyploidisation, and chloroplast introgression, but also taxonomic confusion and misidentifications. Nested within subsect. Patellares is a pair of dwarf species from the Ryukyus Archipelago (Japan) with dwarf habit and 2n = 22, Viola tashiroi and V. iwagawae. These species form adventitious shoots from roots that superficially look like stolons [288]. Becker [248] erected grex Gmelinianae for a heterogeneous group of Central Asian rosette plants with cuneate or spathulate leaves and adnate stipules, which he later incorporated in grex Adnatae [1]. The Gmelinianae is, however, polyphyletic and here we redistribute its members among three sections: sect. Plagiostigma subsect. Patellares with V. gmeliniana, V. perpusilla, and V. turkestanica; sect. Spathulidium with V. spathulata; and sect. Himalayum with V. kunawurensis. The group consisting of V. perpusilla, V. turkestanica, and the similar V. alata, are atypical within subsect. Patellares in having subentire leaves and unmargined style; they however have the characteristic long spurs of that subsection while sect. Himalayum has a short spur.

Photogallery