Sansevieria muhaensis M.Burkart, Yinger, Sikawa & Mollel, 2025

Burkart, Michael, Kavula, Kened Alfred, Constantine, Immaculate Kileo, Mollel, Neduvoto Piniel, Piniely, Luciana Naftal, Sikawa, Robert Augustino & Yinger, Barry R., 2025, Sansevieria bangalalana sp. nov. (Asparagales, Asparagaceae), close to extinction in the wild, and five other narrowly endemic and threatened species of Sansevieria from Tanzania previously unknown to science, European Journal of Taxonomy 1026, pp. 65-106 : 86-94

Sansevieria muhaensis M.Burkart, Yinger, Sikawa & Mollel sp. nov.

urn:lsid:ipni.org:names:77370780-1

Figs 1, 16–19, Table 3

Diagnosis

Sansevieria muhaensis sp. nov. is characterised by its undulate leaf margins ( Fig. 16), its very long, greenish bracts of partial inflorescences in the flowering head ( Fig. 17) and the dark red colouration of the inner rhizome cortex. It is somewhat similar to S. kirkii Baker which also has a median ridge on the leaf abaxial side and similar flower dimensions. In S. kirkii , however, the abaxial leaf ridge is more pronounced and bears several lateral furrows from base to leaf tip which are completely lacking in S. muhaensis . Also, S. muhaensis has longer runners and a dark red rather than dark brown colouration of the inner rhizome cortex which is characteristic of S. kirkii . Further, the outside corolla pattern of S. kirkii is reddish to dark red, not grey as in S. muhaensis . An overview is given in Table 3 .

Etymology

Sansevieria muhaensis sp. nov. is named for the Muha, the tribe associated with the area where this species was found.

Type material

TANZANIA • Kigoma Region, near the limits of Kigoma City; 803 m a.s.l.; 3 Mar. 2020; B. Yinger & R.A. Sikawa YS 0279; on termite mounds in sun; holotype: NHT [ 000001160 ] .

Living specimens ex typo cultivated at TSF and POTSD .

Description

Acaulescent herb, rhizomatous, stemless, vegetative height†† ca 720 mm, 2 green cataphylls and 3–6 leaves per shoot forming a regular rosette ( Figs 16, 18), longest leaf at intermediate position (neither outermost nor innermost) on individual shoots. Rhizome to 250 mm long, diameter ca 36–46 mm, inner cortex colour†† deep red. Leaves up to 900 mm long or slightly longer, to 85 mm wide, lingulatelanceolate, without petiole, moderately falcate to slightly twisted, with a median ridge on the abaxial side and more or less undulate margins (more so in wild-growing plants, Fig. 16), openly u-shaped and thickened, both surfaces smooth with silk gloss, patterned with cloudy blotches anywhere and cloudy transverse bands on some leaves, mostly in their middle and lower parts, the lighter colour covering ca 50% on both surfaces but appears stronger on the abaxial side, strongest on new leaves, with a few dark longitudinal lines on the adaxial side only which do not extend to the leaf tip, lamina central thickness ca 16 mm; leaf base ca 85 mm wide, ca 26 mm thick, margin lined reddish-brown and whitish, awn-like tip to 38 mm long, brown, stiff and almost sharp on new leaves, leathery and flexible on old leaves. Inflorescence terminal on fully-leaved shoot, capitate ( Fig. 18C), ca 350 mm long overall, peduncle ca 290 mm long, 18 mm in diameter, medium green with purplish flecks or spots all over but white-pinkish at the base, patterned with tiny dots and lines, with 8 peduncle bracts to 116 mm long but without hypsophylls, the lowermost with elongate tips, the upper only short-tipped, bases always shell-like, pale greenish with a few to many small dark dots when young, enveloping the flower-head in its first developmental stages, but dry at anthesis; flower-bearing part ca 60 mm long, with 4 flowers per partial inflorescence throughout the inflorescence; bracts of partial inflorescences 42– 33 mm long, 9– 5 mm wide, with 8–3 nerves, pale green when young but dry at anthesis, lanceolate, rather shortly tapering to a short sharp point, without nectaries. Flowers with aromatic odour; pedicels inarticulate, ca 9 mm long, light green; corolla outside coloured greyish before anthesis with greenish tips, with short greyish longitudinal lines on the basal part of the lobes in bud stage, wilting yellowish; tube ca 117 mm long, lobes ca 36 mm long, ca 3 mm wide, curling back at anthesis to 360°; filaments whitish-yellowish, ca 32 mm long, thread-like, open anthers ca 5 mm long, yellowish; style white, straight, ca 155 mm long above ovary, exserted ca 39 mm, stigma translucent-yellowish, ca 1 mm in diameter, ovary ovoid, light green. Fruits and seeds are unknown to us.

Ecology and distribution

Sansevieria muhaensis sp. nov. YS 0279 was collected in the NE part of Kigoma City in Kigoma Region, near the city limits ( Figs 1, 16). There are a number of collections from this area that are probably the same species as YS 0279, but they have not flowered yet. Based on several extended visits to the region, RAS and BRY guess that S. muhaensis was common in the area based on what can still be seen where fragments of nature persist. YS 0279 was found on termite mounds on school grounds. The other collections which are likely to be the same species all were also found growing on termite mounds. The plants remaining are growing in sun or light shade, but it is likely that all were originally growing in moderate to heavy shade of a closed canopy forest. This area is not particularly arid with a short dry season during the coolest part of the year.

Taxonomic remarks

The flower-head of S. muhaensis sp. nov. (subgenus Capitulatus ) is completely clad in peduncle bracts when young, giving it a drumstick appearance ( Fig. 19A). During its further development, the long, lanceolate bracts of the partial inflorescences appear ( Fig. 19B–C), and afterwards the flower buds emerge from behind them. Up to this stage, the inflorescence is greenish coloured ( Fig. 19C). The stretching flower buds then show a greyish colouration on their tubes, lengthening to short longitudinal lines on the basal part of the lobes ( Fig. 18A). The greyish colouration of the flower outsides is maintained during anthesis ( Fig. 18B–C).

The superficially similar Sansevieria kirkii occurs regularly in coastal lowlands of the Indian Ocean in Tanzania and southern Kenya including the offshore islands. Although there are also numerous records from many other areas in tropical Africa that have been suggested to be S. kirkii , we are not aware of any true confirmation of its taxonomic identity. In any case, the altitude of the S. muhaensis type location is ca 800 m, markedly higher than coastal lowlands. Details of the morphological differences are given above in the diagnosis and in Table 3 .

Tentative threat assessment

Critically endangered: CR E.

The limits of Kigoma City are either fully developed with houses, or soon will be. There is a lot of construction going on, and the whole area is platted for housing. Although Kigoma and nearby areas have now been intensively surveyed, this species was not found anywhere else. It is likely that some plants of S. muhaensis sp. nov. might persist for a while in neglected corners here and there, but the future of this species is most probably to be extinct in the wild in less than 3 generations (IUCN criterion E).

A rating of CR most accurately describes this situation according to our data.

Tables

Table 3 (continued on next page). Comparison of Sansevieria sumbawangana M.Burkart, Constantine, Sikawa & Yinger sp. nov.,S. rukwana M.Burkart, Piniely, Sikawa & Yinger sp. nov. and S. muhaensis M.Burkart, Yinger, Sikawa & Mollel sp. nov. with similar species of the subgenus Capitulatus Mbugua ex L.E.Newton & R.H.Webb. The traits of the species compared are taken from Newton (2020) if not stated otherwise: † = from TSF; ‡ = from Brown (1915); § = from the protologue (Webb & Newton 2018); | = from POTSD. ¶ = style length including ovary.

	S. sinus-simiorum	S. bhitalae	S. kirkii	S. sumbawangana sp. nov.	S. rukwana sp. nov.	S. muhaensis sp. nov.
leaves per shoot	8–10 (?)	1(2–3)	1–3 / 2–88	2–5	2–3	3–6
rhizome diameter [mm]	50	50§	20–42|	70	30	36–46
inner colour of rhizome cortex		ochre‡‡	dark brown|	brownish orange	dark reddish orange	deep red
leaf posture	erect to slightly recurved	erect	ascending-spreading to recurved‡	upright to spreading	spreading to almost horizontal	spreading
leaf length [mm]	to 1000	750 (400–900); 1000– 2000††	750–2750	1000	810	900
leaf width [mm]	60	50–70	60–90(to 120|)	210	110	85
max. lamina thickness in central part of leaf [mm]	50	(massive)	8–14‡	20	6	16
pseudo-petiole	missing	missing|	existing‡	missing	missing	missing
lamina transect	massively u-shaped	massively u-shaped|	concave or flattish‡	openly u-shaped to almost flat	flat but u-shaped	openly u-shaped, thickened
leaf margin	rather straight	rather straight|	very wavy‡	somewhat wavy	sinuate	undulate
median ridge on leaf abaxial side	(massive)	(massive)	strong|	missing	missing	existing
leaf colour pattern	inconspicuous to present	yellow-green mottling from prominent to very faint	mottled or transversely banded	almost missing	adaxial cloudy, abaxial transverse bands	cloudy blotches and transverse bands
state of flowering shoot		often lateral, bearing only cataphylls and bracts†	fully-leaved	fully-leaved	fully-leaved	fully-leaved
peduncle length (base to lowermost pedicel) [mm]	290	ca 300	to ca 500	300	163	290
peduncle diameter [mm]	15	15	13‡/15|	20	20	18
peduncle bracts	6	“3 pairs”§	5–6‡	7	4	8
peduncle bracts length [mm]	32–35	30/60 (“Superclone”)§	50–77‡	to 78	46–114	to 116