Encephalartos venetus (Zamiaceae): a new species from the Northern Province

Encephalartos venetus is described from the Northern Province. It resembles E. cupidus R.A

A critical study of the group of species comprising Encephalarlos cupidus R.A. Dyer, E. dolomiticus     Pl ants arborescent, so li tary or suckering from base. Trunk up to 2 m lall (often less?) and about 250 mm thick. covered with leaf hases. [(.'aves numerous, spreading, morc or less straight, glahrous. glaucous, rachis often (but not invariabl y) twisted; petiole lip to 150 mm long: prox imal leaflets progressively reduced lowanJs base of leaf bm only lowermost 1 or 2 reduced to spines; median k:aflets directed towards apex of leaf at angle of about 45°, opposing leaflets almost folded together (with angle of 45° or less hetween them) , incubous ly overlapping, both margins conspicuollsly dentate and apices pungent when plants submature bur entire in malu re stage, 200-170 mm long and 20-24 mOl wide. Male cones lip to 4. cy lindri cal. 280-400 rum long and 85-1 10 mm across, on short stalks 70-85 mm long. glabrous. glaucous; exposed faces of microsporophylls drawn out into drooping beaks toward s central fac ets, other facets not demarcated. Female cOlles up to 2 observed, sessile, ovoid, about 100 rum long and 180 rum across, glabrous, glaucous; exposed faces of megasporophylls more or less smoo th or very slightly wrinkled but with well-defined facets, pyramidally raised towards central facet whi ch is usually less [han 1/, the horizontal di amet er of ex posed face of sporophyll ; seed with bright red (not orange) sarcotesta, about 38 mm long and 24 mm across with sclero t~sta removed. (Figures 1-·1).

Variation
In spite of th e large-scale removal of plants from nature, no large pla nt.s have been encountered in cultivation; all the specimens seen had trunks not exceeding 500 rum in length. Most of these specimens had leaflets characteristically dentate on both margins ( Figure 3b). not unlike E. cupidus R.A. Dyer. Many of these plants have already coned and can therefore be considered to be mature, but probably still represent the sub-adult stage in which the fo li age characteristics arc still those o f the juvenile st age (manifested in spinescence of the leaflets). In female cones, the cemral facet of the megasporophylJ is usuaJly conspicuously small, less than 1/3 the horizontal diameter of the exposed face of the sporophyll (Figure 2e). Ste),11 318 (PRE), plus phot ographs taken in the habitat (cf. Figure la) by Mr S.P. Fourie, suggest that pla nts attain a trunk length of up to 2.5 m, and that the adul tstage leaflets arc entire (Figure 2c). In the female cone of Steyn 318, the central facet of the exposed sporophyll face is markedly larger, alm ost I/Z the hori zontal diameter of the exposed face ( Figure 2f). I have no reason not to include this material in E. vellelllS.

Affinities and diagnostic features
E. venetlls ci osery resembles E. cupidus (Dyer 1971b) in its glaucous foliage, toothed leaflets (in its sub-mature stage), and the morphol ogically similar fema le cones; but differs in being a muc h larger pl ant of arboresce nt habit, and with the ex posed faces of the microsporophylls drawn out to a much greater exten t into a beak-like structure. The mature-stage leanets are mostly entire, and consp icuously large. The impression gained was that the co nes of E. vcneltls are more glaucous (hence the specific epithet) and very slightly wrinkled, co mpared with the dark green and smooth cones of E. cupidus.
As in E. dolomiticlls, the rachis of the leaf is sometimes twisted. S. Afr. J. Bol. 1996. 62(2) The female cones resemble those of E. dyerianus Lavranos & Goode (cf. Robbertse et (/1. 1988a) and E. il1opil1us (Dye r 1971a) in the more or less smooth -facetted , moderately rai sed, exposed faces of the sporophylls and the glaucous green pi gmentation , but in the male cones, the exposed faces of the sporophylls are drawn out into beak-like structures instead of being only slightly raised.

Phenology
In its natural habitat, disinteg rating female cones were observed in mid-June (Steyn 318), which is earlier than expected; but in cultivation in Pretoria. female cones on ly started falling apart towards the end of September. In June, the male cones in habitat had already dried out, and observations on cultivated plants in Pretoria and Stellenbosch suggest th at the cones appear in mid-December and shed the pollen between mid-January and mid-April. It is not certain to what extent regeneration from seed take s place in nature, but taking into account the dryness of the habitat, it can be surmised that the seeds germinate towards midsummer, at the height of the rainy seaso n, rather than staying dormant until the following summer. In cu ltivation, fertile seeds have been produced foll owing hand pollination.

Geographical distribution and habitat
E. velletlls occu rs in the Northern Province Drakensberg ( Figure  4). Due to its restricted distribution and the low number of individual s remaining in nature, the precise locality is not revealed. It has been reported to occur in low, open woodland, on cliff ledges, in direct sunlight (Figure 1).

Conservation status
This is yet another spec ies of the former Transvaal which seems to be on the brink of extinction. Very few specimens remain in nature, and these occur widely scattered, even though the total distributi on as known at present is fairly restricted.

Note
A specimen from the same general area as the type collection (Zul1ckel 20. PRE!) superficially resembles this species. but its leaflets differ in having corrugated abaxial surfaces, like E. paucidentatus Stapf & Burtt Davy. It is considered prudent to withhold judgement on its affiliation until more material can be studied in the field. Figure 4 Encephalarros venetus: known geographical di stribution.
A number of live specimens were collected and distributed to growers in the early 1970s under the name Encephalartos dolomilien, several years before this trade name was adapted to E. dolomiticus by Lavranos & Goode (1988). Several of these were studied, and the reader should not be mislead by the fact that only two specimens with collecting data are cited: -Locality withheld, Steyn 3J6 (including microsporophylls -type) (K, PRE); SIcYl1318 (including megasporophylls) (K, PRE).