Isatis

Isatis is a genus of flowering plants in the family Brassicaceae, native to the Mediterranean region east to central Asia. Its genus name, Isatis, derives from the ancient Greek word for the plant, ἰσάτις. The genus includes woad (Isatis tinctoria). Due to their extremely variable morphology, the Asian species in particular are difficult to determine; the only reliable diagnostic feature is the ripe fruit. They are (usually) biennial or perennial herbaceous plants, often bluish and hairless or downy hairy with the upright stem branched.
Description
They are annual, biennial or perennial, branched herbs, usually glabrous and glaucous except silique. Basal leaves generally elliptic-oblong, sessile; sessile caulinary, rounded to oval-oblong.
The hermaphrodite flowers are fourfold double perianth. The four sepals are ascending to upright. The four yellow to off-white or lilac-white petals are at least as long as the sepals. They have six stamens with very small, egg-shaped or elongated-round anthers. There are nectar glands. Racemose is branched or paniculated, ebracted, inflorescence, often reaching lax and elongated in the fruit.
The fruit is a generally linear silique, oblong-cuneate to suborbicular, indehiscent, flattened laterally, unilocular, little to conspicuously winged, glabrous or with tiny hairs.
Species
Currently accepted species include:
Isatis afghanica Hadac & Chrtek
Isatis amani P.H.Davis
Isatis apennina Ten. ex Grande
Isatis apscheronica N.Busch
Isatis aptera (Boiss. & Heldr.) Al-Shehbaz, Moazzeni & Mumm.
Isatis arenaria Azn.
Isatis armena L.
Isatis arnoldiana N.Busch
Isatis aucheri Boiss.
Isatis biscutellifolia Boiss. & Buhse
Isatis bitlisica P.H.Davis
Isatis boissieriana Rchb.f.
Isatis brachycarpa C.A.Mey.
Isatis brevipes (Bunge) Jafri
Isatis bullata Aitch. & Hemsl.
Isatis bungeana Seidlitz
Isatis buschiana Schischk.
Isatis callifera Boiss. & Balansa
Isatis campylocarpa Boiss.
Isatis canaliculata (Vassilcz.) V.V.Botschantz.
Isatis candolleana Boiss.
Isatis cappadocica Desv.
Isatis cardiocarpa (Trautv.) Al-Shehbaz, Moazzeni & Mumm.
Isatis caucasica N.Busch
Isatis cochlearis Boiss.
Isatis constricta P.H.Davis
Isatis costata C.A.Mey.
Isatis davisiana H.Misirdali ex P.H.Davis, R.R.Mill & Kit Tan
Isatis demiriziana H.Misirdali ex P.H.Davis, R.R.Mill & Kit Tan
Isatis densiflora (Bunge ex Boiss.) D.A.German
Isatis deserti (N.Busch) V.V.Botschantz.
Isatis djurjaedae Coss. & Durieu
Isatis elegans (Boiss.) Hadac & Chrtek
Isatis emarginata Kar. & Kir.
Isatis erzurumica P.H.Davis
Isatis floribunda Boiss. ex Bornm.
Isatis frigida Boiss. & Kotschy
Isatis frutescens Kar. & Kir.
Isatis gaubae Bornm.
Isatis glastifolia (Fisch. & C.A.Mey.) Al-Shehbaz, Moazzeni & Mumm.
Isatis glauca Aucher ex Boiss.
Isatis grammotis Kit Tan
Isatis gymnocarpa (Fisch. ex DC.) Al-Shehbaz, Moazzeni & Mumm.
Isatis harsukhii O.E.Schulz
Isatis hirtocalyx Franch.
Isatis huber-morathii P.H.Davis
Isatis iberica Steven
Isatis jacutensis (N.Busch) N.Busch
Isatis karjaginii Schischk.
Isatis kotschyana Boiss. & Hohen.
Isatis kozlovskyi Grossh.
Isatis laevigata Trautv.
Isatis latisiliqua Steven
Isatis leuconeura Boiss. & Buhse
Isatis littoralis Steven
Isatis lockmanniana Kotschy ex Boiss.
Isatis lusitanica L.
Isatis mardinensis P.H.Davis & H.Misirdali
Isatis maxima Pavlov
Isatis microcarpa J.Gay ex Boiss.
Isatis minima Bunge
Isatis multicaulis (Kar. & Kir.) Jafri
Isatis oblongata DC.
Isatis odontogera (Bordz.) D.A.German
Isatis ornithorhynchus N.Busch
Isatis pachycarpa Rech.f., Aellen & Esfand.
Isatis pinnatiloba P.H.Davis
Isatis platyloba Link ex Steud.
Isatis praecox Kit. ex Tratt.
Isatis raimondoi Di Grist., Scafidi & Domina
Isatis raphanifolia Boiss.
Isatis rugulosa Bunge ex Boiss.
Isatis sabulosa Steven ex Ledeb.
Isatis sevangensis N.Busch
Isatis sivasica P.H.Davis
Isatis spatella P.H.Davis
Isatis spectabilis P.H.Davis
Isatis steveniana Trautv.
Isatis stocksii Boiss.
Isatis subdidyma (N.Busch) V.E.Avet.
Isatis takhtajanii Avet.
Isatis tinctoria L.
Isatis tomentella Boiss. & Balansa
Isatis trachycarpa Trautv.
Isatis turcomanica Korsh.
Isatis undulata Aucher ex Boiss.
Isatis violascens Bunge
Isatis zarrei Al-Shehbaz, Moazzeni & Mumm.
References
Brassicaceae
Brassicaceae genera