712. EUCOMIS VANDERMERWEI

The history, ecology, genome size and cultivation requirements of the high altitude, threatened South African geophyte Eucomis vandermerwei I. Verd. are discussed. A watercolour plate, habitat photographs and key to the Eucomis species are provided.     

755. EUCOMIS AMARYLLIDIFOLIA

The summer‐growing dwarf geophyte Eucomis amaryllidifolia Baker is native to South Africa's Eastern Cape. Following an investigation into genome sizes of all species of Eucomis, the taxon is returned from subspecies to species status, and details of its history, taxonomy and cultivation are given, accompanied by a colour plate.     

Karyotype of Ornithogalum chionophilum (Hyacinthaceae)

A karyotype of Ornithogalum chionophilum is presented. The relationship between this species and O. lanceolatum, O. cuspidatum and O. montanum is discussed.     

Taxonomy of the genusBrimeura (Hyacinthaceae)

A taxonomic reevaluation of two little-knownBrimeura taxa,B. fontqueri (Pau)Speta andB. duvigneaudii (L. Llorens)Rosselló et al., has been made.Brimeura fontqueri, described from the Iberian peninsula, has been put into synonymy ofB. amethystina (L.)Salisb., since it could not be distinguished on morphological, anatomical or cytogenetic grounds.Brimeura duvigneaudii, from the Balearic Islands, is closely related toB. amethystina and has 2n=28 chromosomes. It differs from the latter by its naked bulbs lacking dark cataphylls, and its narrower leaves and whitish corollas. Accessory chromosomes are reported for the first time in the genus. Karyological instability (with chromosome numbers ranging from 2n=28 to 42) is reported for a population ofB. fastigiata (Viv.)Chouard. A key to the recognized taxa ofBrimeura is provided.     

Studies on systematic embryology inScilla (Hyacinthaceae)

Scilla persica and 5 species of the so-calledS. hohenackeri group, namely,S. furseorum, S. puschkinioides, S. vvedenskyi, S. hohenackeri, andS. greilhuberi, have been investigated embryologically with special reference to embryo sac and endosperm development.Polygonum-type embryo sac development was stated inS. puschkinioides andS. greilhuberi. 8-nucleate, normally structured embryo sacs, which could not be specified further due to sparse availability of the material, were stated inS. furseorum, S. vvedenskyi, andS. hohenackeri. InS. persica the embryo sac develops according to the bisporicAllium-type. In most species endosperm development was stated to be nuclear, exceptS. hohenackeri, where the type could not be specified. Other traits of possible taxonomic significance are the number of layers in the outer integument, which is mostly 4, or 5–6 inS. furseorum, and the occurrence of polyploid versus haploid and early degenerating antipodal nuclei, the latter occurring only inS. persica andS. furseorum. These embryological characters may be useful for assessing taxonomic relationship of the present species with other allied groups withinScilla, in particular, theS. siberica alliance,S. messeniaca, and theS. bifolia alliance. TheAllium-type embryo sac, which occurs inS. persica, is also characteristic for theS. siberica alliance, and may be a common derived character. Lack of antipodal polyploidization, as characteristic forS. persica andS. furseorum, occurs also in theS. siberica alliance, and is perhaps another common derived trait indicating phylogenetic relationship. Nuclear endosperm development is more frequent in spring-flowering squills than helobial development, which has previously been stated inS. messeniaca, some species of theS. siberica alliance, and inS. litardierei. While helobial endosperm may be primitive forHyacinthaceae in general, it may, by reversal, also occur as a derived character, at least in some species of theS. siberica alliance.     

Synopsis of Hyacinthaceae in tropical East and North-East Africa

Nine genera of Hyacinthaceae, Albuca, Bowiea, Dipcadi, Drimia, Drimiopsis, Lede-bouria, Ornithogalum, Schizobasis and Scilla , with a total of 34 species, are recognized in Ethiopia, Somalia, Djibouti, Uganda, Kenya and Tanzania. One new species, Ledebouria urceolata , is described from Ethiopia. New combinations are Drimia simensis, Drimiopsis fischeri, Ledebouria sornaliensis, L. kirkii, L. edulis and L. cordifolia . Several names are reduced to synonymy and some are lectotypified. Keys to all taxa are given.     

Cytotaxonomy of autumnal flowering species of Hyacinthaceae from Algeria

Cytotaxonomic investigations of the autumn-flowering squills, Prospero autumnale (L.) Speta ≡ Scilla autumnalis L., Prospero obtusifolium (Poir.) Speta ≡ Scilla obtusifolia Poir., Barnardia numidica (Poir.) Speta ≡ Scilla numidica Poir., and Hyacinthoides lingulata (Poir.) Rothm. ≡ Scilla lingulata Poir. were performed in 20 populations from northern Algeria located between Tipasa and La Vieille Calle. Various chromosome numbers were found, including a new cytotype, 2n = 8, for the flora of Algeria, concerning plants identified as Prospero obtusifolium (Poir.) Speta [including P. fallax (Steinh.) Speta = S. autumnalis L. ssp. fallax (Steinh.) Batt.]. The numbers 2n = 14, 28, and 42 correspond, respectively, to diploid, tetraploid, and hexaploid levels of P. autumnale s.l. [including P. pulchellum (Munby) Speta ≡ Scilla pulchella Munby = S. autumnalis var. pulchella (Munby) Batt.], with x = 7. The cytotypes of Barnardia numidica (Poir.) Speta with 2n = 18 and Hyacinthoides lingulata (Poir.) Rothm. with 2n = 16 chromosomes were confirmed.     

Bufadienolides from Drimia robusta and Urginea epigea (Hyacinthaceae)

Two bufadienolides, 6beta-acetoxy-3beta,8beta,14beta-trihydroxy-12-oxobufa-4,20,22-trienolide and 14beta-hydroxybufa-3,5,20,22-tetraenolide were isolated from the dichloromethane extract of the bulbs of Drimia robusta and the methanol extract of the bulbs of Urginea epigea, respectively. The bulbs of Drimia robusta also yielded several known compounds, 6beta-acetoxy-3beta,8beta,12beta,14beta-tetrahydroxybufa-4,20,22-trienolide (12beta-hydroxyscillirosidin) from the dichloromethane extract and three common aromatic acids, 4-hydroxy-3-methoxybenzoic acid, 3,4-dihydroxybenzoic acid, and trans-3-(4'-hydroxyphenyl)-2-propenoic acid from the ethyl acetate extract.     

Bufadienolides from Drimia robusta and Urginea altissima (Hyacinthaceae)

The bufadienolides, 6beta-acetoxy-3beta,8beta,12beta,14beta-tetrahydroxybufa-4,20,22-trienolide (12beta-hydroxyscillirosidin) (1) and 14beta-hydroxybufa-4,20,22-trienolide 3beta-O-[alpha-L-rhamnopyranosyl-[(1-->4)-beta-D-glucopyranosyl]-(1-->3)-alpha-L-rhamnopyranoside] (urginin) (2) were isolated from Drimia robusta and Urginea altissima, respectively.     

A new low chromosome number forOrnithogalum tenuifolium (Hyacinthaceae)

A new chromosome number (2n=4) forOrnithogalum tenuifolium Delaroche is reported. The new chromosome race is postulated to have originated by a Robertsonian translocation from a Southern African chromosome race with six chromosomes, and represents thus the final step in a series of decreasing basic number of the species.     

Polyploidy and karyotype variation in Turkish Bellevalia (Hyacinthaceae)

There are 20 Bellevalia species in Turkey, half of which are endemic. Chromosome numbers are known for 15 species. A chromosome survey of 145 Bellevalia individuals showed that the karyotype is remarkably stable. All are based on x  = 4. The majority are diploid with 2 n  = 8, but there is also a polyploid series of 2 n  = 16, 24 and 32. Aneuploidy occurs only at the octoploid level. Eleven individuals had metacentric B chromosomes, one had acrocentric Bs and one had telocentric Bs. Bellevalia pycnantha and B. paradoxa are morphologically similar, with B. pycnantha reduced to a synonom of B. paradoxa .  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 143 , 87–98.     

Cytogeographical studies of Hyacinthaceae in Africa south of the Sahara

The geographical distribution of different karyotypes in Tropical African genera of Hyacinthaceae is studied. In Albuca, Dipcadi, Drimia (including Urginea), and Drimiopsis there seem to be a general trend of increasing level of ploidy and/or basic number. There is also a tendency of increasing karyotype asymmetry from the south towards north and west. Southern Africa is therefore probably a centre of dispersal (and origin?) for these genera. In the subgenus Urophyllon of Ornithogalum the cytological conditions are in accordance with a hypothesis of northern origin and migration via East Africa towards south and west. Several new chromosome numbers are presented.