Krenakanthus (subgen. of Orthophytum) Leme, S. Heller & Zizka[as Krenakanthus (subgen. of Orthophytum) ]

Diagnose: —Diagnosis:—This new subgenus differs from the remaining Orthophytum subgenera mainly by: leaves in most part chartaceous (vs. coriaceous or subcoriaceous), leaf blades glabrescent or glabrous (vs. usually distinctly lepidote at least abaxially) with undulate margins (vs. not undulate), flowers 4.2–5.5 cm long (vs. usually to 3 cm long), fragrant (vs. odorless), sepals connate (vs. free), petals broadly spathulate (vs. linear-lanceolate to narrowly spathulate), spreading at anthesis (vs. erect to suberect with recurved apex only) and flaccidescent afterwards (vs. remaining erect), rose-lilac to lilac-purple toward the apex (vs. usually white or green), petal blades suborbicular (vs. ovate, obovate or elliptic), petal appendages thick, cupuliform (vs. echinatiform or sacciform, rarely cupuliform), stamens deeply included and not visible (vs. not deeply included, partially to distinctly visible), and the conduplicate-spiral stigma (vs. simple-dilated, simple-erect or simplepatent).

Observations: —Positioned in the strongly supported “Orthophytum clade”, O. roseolilacinum is a unique species without closer morphological affinity to any known species, despite its weakly supported sister position to Orthophytum subg. Orthocryptanthus (fig. 5), with which it shares the same geographical range. Its general vegetative appearance characterized by the combination of long caulescent habit, and comparatively thintextured leaves with undulate margins give it a very distinct appearance similar to some species of Rokautskyia (e.g., R. exaltata and R. pseudoglazioui). It also shares the caulescent habit and sessile inflorescence with three species of subg. Capixabanthus (i.e., O. pseudovagans, O. vagans, and O. zanonii).

In general, it differs from remaining subgenera of Orthophytum by having leaves that are for most part chartaceous (vs. coriaceous or suboriaceous), leaf blades glabrescent or glabrous (vs. usually distinctly lepidote at least abaxially) with undulate margins (vs. not undulate), inflorescence sessile (vs. usually on a distinct peduncle, except three species of subg. Capixabanthus and Sincoraea), flowers 42–55 mm long [vs. usually to 30 mm long, except for the outlier O. macroflorum Leme & M. Machado (2005: 171) with 50–65 mm long flowers], fragrant (vs. scentless), sepals connate (vs. free), petals broadly spathulate (vs. linear-lanceolate to narrowly spathulate), spreading at anthesis (vs. erect to suberect with recurved apex) and flaccidescent afterwards (vs. remaining erect), rose-lilac to lilac-purple toward the apex (vs. usually white or green), petal blades suborbicular (vs. ovate, obovate or elliptic), petal appendages cupuliform (vs. echinatiform, sacciform or rarely cupuliform in subg. Capixabanthus), stamens deeply included and not visible (vs. not deeply included, partially to distinctly visible), and the conduplicate-spiral stigma (vs. simple-dilated, simple-erect or simple-patent).

Similarities of O. roseolilacinum with Rokautskyia – which is highly supported as sister to the whole Orthophytum clade in which subg. Krenakanthus is included – are: fragrant flowers and the broadly spathulate petals with suborbicular blades spreading at anthesis (figs. 12 E, 15 D), and the shaded Atlantic Forest habitats (figs. 12 A, B, 15 A, C). The combination of rose-lilac to lilac-purple petals (vs. white, green, yellowish or orange), the stamens deeply included and not visible (vs. not deeply included and at least partially visible), and the conduplicate-spiral stigma blade (vs. conduplicate-patent, cylindric-distent, simple-dilated, simple-erect, simpleimbricate or simple-patent) has never been reported for any other member of the “Cryptanthoid complex”, despite a similar color pattern that is also documented for O. vasconcelosianum.

Despite other differences in flowers features, O. roseolilacinum has thick, cupuliform petal appendages (fig. 20 L), very similar to those of the majority of the species of subg. Capixabanthus (figs. 20 I to K). The cupuliform type is observed in O. duartei, O. foliosum, O. rubiginosum, and O. zanonii, while the sacciform type in O. compactum and O. vagans. Orthophytum pseudovagans has both cupuliform and sacciform petal appendage types. In contrast, petal appendages are usually echinatiform in Orthophytum subg. Orthophytum (figs. 20 E to H) and absent in Rokautskyia.

Edited from : Leme et al. 2017b. (protologue) New circumscription of Cryptanthus and new Cryptanthoid genera and subgenera (Bromeliaceae: Bromelioideae) based on neglected morphological traits and molecular phylogeny .