CHROMOSOME NUMBERS IN THE COMPOSITAE. XIV. LACTUCEAE

Reports of 150 original chromosome counts are recorded, including reports of 22 genera and 57 species and subspecific taxa in tribe Lactuceae. Also included are first reports for 12 specific or subspecific taxa. x = 9 appears to be the ancestral base of the tribe. Chromosome numbers are known for over 85% of the genera of the tribe and the frequency of polyploidy is ca. 23%, which is about one-half that of the angiosperms.     

First record of Miocene crustaceans from Hormozgan Province,Southern Iran

Four decapod crustacean species from the Middle Miocene Mishan Formation of Hormozgan Province, Southern Iran are described. Three species of leucosiid crabs represent the first fossil record for their respective genera outside the Indo-Pacific region. The oldest records for Leucosia sensu lato, Phylira sensu lato, and Arcania are from Middle Miocene deposits of the Indo-Pacific, and thus their paleobiogeographic distribution is extended for this lapse of time. Harpactocarcinus miocenicus n. sp. represents the youngest and most oriental occurrence for a typically Eocene genus, whose species are known mainly from Central Europe. This contribution represents the first formal report for Tertiary crustaceans from Iran.     

Molecular Phylogeny of Eupatorieae (Asteraceae) Estimated from cpDNA RFLP and its Implication for the Polyploid Origin Hypothesis of the Tribe

Neomirandea (x=17 and 25), Ageratina (x=17) and Sclerolepis (x=15) with the higher chromosome base numbers, and the other includes Mikania (x=17) and the remaining genera with lower chromosome base numbers (x=10–11). However, the monophyly of the former clade is supported with a low bootstrap value. In the latter clade, Mikania (x=17) diverged first, then Stevia (x=11), and finally eight genera with x=10 diverged in succession. This result supports the hypothesis that the genera in the tribe Eupatorieae with x =10 evolved from an ancestor with a higher base number, and the tribe is of polyploid origin. Received 13 September 1999/ Accepted in revised form 20 January 2000     

Phylogeny and evolution of Mesozoic and extant lineages of Histeridae (Coleoptera), with discovery of a new subfamily Antigracilinae from the Lower Cretaceous

In order to place a newly discovered species Antigracilus costatus gen. sp. n. from the Lower Cretaceous Yixian Formation (China) and to assess previously unplaced fossil taxa, we investigated the relationships of extant and extinct lineages of Histeridae based on three data sets: (i) 69 morphological characters belonging to 48 taxa (representing all 11 subfamilies and 15 of 17 tribes of modern Histeridae); (ii) partitioned alignment of 6030 bp from downloaded nucleotide sequences (28S, CAD, COI, 18S) of 50 taxa (representing 10 subfamilies and 15 of 17 tribes of modern Histeridae); and (iii) a combined morphological and molecular dataset for 75 taxa. Phylogenetic analyses of the morphology and combined matrices recovered the new Lower Cretaceous taxon as a sister group to remaining Histeridae and it is placed in †Antigracilinae subfam. n. †Antigracilinae constitutes the earliest record of Histeridae from the Lower Cretaceous Yixian Formation (∼125 Myr), backdating the minimum age of the family by 25 Myr from the earliest Cenomanian (~99 Myr) to the Barremian of the Cretaceous Period. Our molecular phylogeny supports Histeridae to be divided into seven different clades, with currently recognised subfamilies Abraeinae (sensu lato), Saprininae, Chlamydopsinae, and Histerinae (sensu lato) recovered as monophyletic, while Dendrophilinae, Onthophilinae, and Tribalinae are polyphyletic taxa. The Burmese amber species †Pantostictus burmanicus Poinar & Brown is placed as a sister group to the tribe Plegaderini (Abraeinae) and was assigned as a new tribe Pantostictini trib. n. Both molecular and combined phylogenies recovered the subfamilies Trypanaeinae and Trypeticinae deeply within the subfamily Abraeinae (sensu lato), and they are downgraded into Trypanaeini stat. n. and Trypeticini stat. n.     

CHROMOSOME NUMBERS IN COMPOSITAE. III. SENECIONEAE

Ornduff , Robert (Duke U., Durham, N. C), Peter H. Raven , Donald W. Kyhos , and A. R. Kruckeberg . Chromosome numbers in Compositae. III. Senecioneae. Amer. Jour. Bot. 50(2): 131–139. Illus. 1963.—Chromosome counts are reported for 75 taxa of tribe Senecioneae (Compcsitae) and are listed with a generic summary of previous counts in the tribe. First counts are reported for Bedfordia, Crocidium, Dimeresia, Gamolepis, Lepidospartum, Luina, Peucephyllum, Telradymia, and the first definite count recorded for Euryops. New numbers are added to those previously known in Arnica and Psathyrotes. Intraspecific differences in ploidy-level are reported in 4 North American species of Senecio. Although chromosome numbers are useful as an aid in delimiting some genera of Senecioneae, they are of little use in circumscribing genera peripheral to Senecio, primarily because of the great range of chromosome numbers of that genus. Chromosome numbers support suggestions based on morphological considerations that genera such as Crocidium and Dimeresia do not belong in Senecioneae, whereas chromosome number and morphology of the plants virtually prohibit the removal of such genera as Peucephyllum, Lepidospartum, and Telradymia from Senecioneae, despite the suggestions of several recent authors. It is proposed that the base number for the tribe is 10 and that the tribe originated in the Old World, with subsequent widespread migration and diversification.     

CHROMOSOME NUMBERS IN COMPOSITAE. IX. HAPLOPAPPUS AND OTHER ASTEREAE

Reports of 209 original chromosome counts are made for the tribe Astereae of Compositae, including first counts for two genera and 46 species or subspecies. With over 80 % of the species counted, chromosome numbers are now available for all North American sections of Haplopappus. Two major groupings are apparent: one, with basic numbers of x = 4, 5, or 6, is basically herbaceous; the other, with x = 9, consists of shrubs or subshrubs. Aneuploidy is known only in the “herbaceous” group of Haplopappus, and polyploidy is more extensive there than in the woodier group of sections.     

CHROMOSOME NUMBERS IN THE COMPOSITAE: COLOMBIAN SPECIES

Chromosome numbers are presented for 76 species belonging to 35 genera of Compositae from Colombia. Thirty-nine species and three genera, Espeletia (x = 19), Steiractinia (x = 14), and Vasquezia (x = 19), are reported for the first time. New base numbers or chromosome series are recorded in Baccharis (B. nitida, n = 25), Calea (C. caracasana, n = 24), and Liabum (L. mega-cephalum, n = 10).     

天门冬科黄精族细胞学研究进展

在全面收集和整理黄精族染色体数据的基础上,对国内外有关黄精族各类群间的染色体数目和倍性的变化规律进行了总结,并从染色体的多倍化和非整倍化与系统发育关系和地理分布方面探讨了黄精族内各属的起源和演化关系问题。黄精族包括黄精属、舞鹤草属、异黄精属和竹根七属,共约100余种,其中舞鹤草属(x=18)、异黄精属(x=16)和竹根七属(x=20)的染色体基数稳定,而黄精属染色体基数波动较大,主要为x=8~16,既有多倍化也有非整倍化现象。染色体数据表明黄精族4个属的染色体进化模式各不相同,揭示了黄精族内染色体从高基数向低基数演化的规律;各属内染色体的演化主要是体现在二倍体水平上的核型变异,多倍化在本族中不占主导地位;仅黄精属内伴有非常强烈的非整倍化现象;细胞学证据与分子系统发育的结果比较吻合,为黄精族内属间以及属下的系统发育与进化提供了重要的参考资料。     

Evolutionary trends in Iridaceae: new cytogenetic findings from the New World

With the present work, we aim to provide a better understanding of chromosome evolutionary trends among southern Brazilian species of Iridoideae. Chromosome numbers and genome sizes were determined for 21 and 22 species belonging to eight genera of Tigridieae and two genera of Trimezieae, respectively. The chromosome numbers of nine species belonging to five genera are reported here for the first time. Analyses of meiotic behaviour, tetrad normality and pollen viability in 14 species revealed regular meiosis and high meiotic indexes and pollen viability (> 90%). The chromosome data obtained here and compiled from the literature were plotted onto a phylogenetic framework to identify major events of chromosome rearrangements across the phylogenetic tree of Iridoideae. Following this approach, we propose that the ancestral base chromosome number for Iridoideae is x = 8 and that polyploidy and dysploidy events have occurred throughout evolution. Despite the variation in chromosome numbers observed in Tigridieae and Trimezieae, for these two tribes our data provide support for an ancestral base number of x = 7, largely conserved in Tigridieae, but a polyploidy event may have occurred prior to the diversification of Trimezieae, giving rise to a base number of x₂ = 14 (detected by maximum‐parsimony using haploid number and maximum likelihood). In Tigridieae, polyploid cytotypes were commonly observed (2x, 4x, 6x and 8x), whereas in Trimezieae, dysploidy seems to have been the most important event. This feature is reflected in the genome size, which varied greatly among species of Iridoideae, 4.2‐fold in Tigridieae and 1.5‐fold in Trimezieae. Although no clear difference was observed among the genome sizes of Tigridieae and Trimezieae, an important distinction was observed between these two tribes and Sisyrinchieae, with the latter possessing the smallest genome sizes in Iridoideae. © 2014 The Linnean Society of London, Botanical Journal of the Linnean Society, 2014, 177 , 27–49.     

Phylogeny of the tribe Empoascini (Hemiptera: Cicadellidae: Typhlocybinae) based on morphological characteristics,with reclassification of the Empoasca generic group

A morphology‐based phylogenetic analysis of the tribe Empoascini (Hemiptera: Cicadellidae: Typhlocybinae) is presented for 58 of 83 formerly recognized genera based on 99 morphological characters of adults. The results support excluding the New World Beamerana generic group from Empoascini. The remaining genera of Empoascini were recovered as a monophyletic sister group of Dikraneurini. Previously recognized tribes Jorumini and Helionini are derived from within Empoascini and are considered synonyms of the latter tribe. Three previously recognized informal generic groups, the Empoasca group, Alebroides group and Usharia group were paraphyletic but the Ficiana group was recovered as monophyletic based on five synapomorphies. Genera previously placed in the Alebroides group represent at least six independent lineages, indicating that the hind wing character separating this group from the Empoasca group (CuA and MP veins free) is highly homoplasious. Empoasca (sensu lato) is also paraphyletic. Thus, twelve previously recognized subgenera of Empoasca are elevated to genus status and five species groups of Empoasca from the New World are recognized as separate new genera. Sikkimasca Dworakowska, 1993 is treated as synonym of Marolda Dworakowska, 1977 based on the phylogeny. Biogeographic analysis suggests that Empoascini most likely first evolved in the Oriental region and spread to other biogeographic realms more recently by multiple independent invasions.     

Cytogeography of Gentianaceae–Exaceae in Africa,with a special focus on Sebaea: the possible role of dysploidy and polyploidy in the evolution of the tribe

Unlike other tribes of Gentianaceae, Exaceae have so far received little attention regarding their karyological evolution. Indeed, only 35 chromosome number counts (19 species) have been referenced to date, representing only a negligible fraction of the tribal diversity. In this paper, we performed an intensive chromosome count on material collected in the field (South and central Africa, plus Madagascar), encompassing 155 populations and c. 60 species from four genera of Exaceae, including Exacum, Ornichia, Sebaea and Tachiadenus. Fifty nine species (14 Exacum, one Ornichia, 42 Sebaea and two Tachiadenus) were examined for the first time, revealing a broad set of chromosome numbers (2n = 18, 28, 32, 36, 42, 56) and the occurrence of polyploid systems within Exacum and Sebaea. These results allow us to postulate x = 7, 8 or 9 as possible base chromosome numbers for Exaceae and emphasize the importance of both dysploidy and polyploidy processes in the evolution of the tribe. Finally, chromosome numbers appear to be associated to some morphological or geographical traits, suggesting new systematic combinations and likely active speciation patterns in the group. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 158 , 556–566.     

CHROMOSOME NUMBERS IN COMPOSITAE VIII: HELIANTHEAE

One hundred and ninety-three new counts are reported for the tribe Heliantheae of Compositae, mostly based on determinations of meiotic material, including first counts for the genera Adenothamnus, Chrysogonum, Enceliopsis, Guardiola, Isocarpha, Lipochaeta, Otopappus, and Oyedaea, as well as first counts for 66 species. The original counts are discussed in relation to those previously reported for the tribe, by genera and subtribe. Two-thirds of the approximately 150 genera and more than a third of the roughly 1500 species have now been examined. The incomplete knowledge of generic relationships in the tribe often make the interpretation of these chromosome numbers difficult. Three observations are documented and discussed: (1) genera with low chromosome numbers are few; (2) genera with aneuploid series are abundant; and (3) the original basic chromosome number in the tribe is probably in the range of x = 8 to x = 12.     

Chromosome number evolution in the tribeBrassiceae (Brassicaceae): Evidence from isozyme number

Variation in isozyme number was used to assess the evolution of haploid chromosome numbers (n=6–75) and systematic relationships in the tribeBrassiceae, which is believed to be one of the few monophyletic tribes in theBrassicaceae. Ten enzyme systems were surveyed among 108 species in 35 genera of tribeBrassiceae and for 11 species from seven other tribes. The data indicated that taxa with n=7–13 and n=14–18 were similar in isozyme number, suggesting that genera with n=14–18 did not arise from polyploidy (i.e. entire duplication) of the n=7–13 genomes. These results suggest that aneuploidy and/or chromosome fusion/splitting have played a more significant role than polyploidy in the evolution of higher base chromosome numbers in the tribe. The detection of widespread isozyme duplication in the tribe is consistent with reports of extensive gene duplication in theBrassica crop species, and suggests that the common ancestor of the tribe already had undergone a polyploid event, i.e. complete genome duplication, prior to aneuploid divergence. Inheritance studies conducted onSinapis arvensis showed that segregation ratios at seven loci (Fbp-2,Gpi-2,Idh-2,Pgm-2,Pgm-2,Tpi-1,Tpi-1) conformed to those expected under Mendelian inheritance. Isozyme duplications were phylogenetically informative at various taxonomic levels in the tribe. In particular, duplications for cytosolic phosphoglucomutase (Pgm-2,Pgm-2) and plastid triosephosphate isomerase (Tpi-1,Tpi-1) were evident in 33 of the 35 genera examined, supporting the monophyletic status of theBrassiceae with the inclusion ofOrychophragmus and the exclusion of controversial membersCalepina andConringia.     

Phylogenetic relationships of vespertilionid genera (Mammalia: Chiroptera) as revealed by karyological analysis

Banded karyotypes of 50 species belonging to 23 genera were analyzed. The diploid chromosome numbers ranged from 26 to 50. For karyotypic comparison we used a 44 chromosomes karyotype, consisting of 4 metacentric and 17 acrocentric autosomes, as “basic karyotype”. Almost all of its 25 autosomal arms could be identified in each individual karyotype. In 8 chromosomes, i. e. 1/2, 7, 11, 12, 13, 15, 23 and X, small inversions were detected. As a result, each of the chromosomes mentioned occurs in two states which differ slightly in their banding patterns. These were used as character states in the cladistic analysis together with other chromosomal rearrangements. The implications drawn from the cladogram obtained are: The Miniopterinae clearly belong to the Vespertilionidae but are the first to branch off from the common stem. The tribe Myotini should be raised to the rank of a subfamily. Within the largest subfamily Vespertilioninae, one autapomorphic chromosomal character was found for each of the tribes Vespertilionini and Pipistrellini. In addition, both tribes are distinguished from the other Vespertilioninae tribes by two synapomorphic features. These results allow for the first time an unequivocal classification of the systematically difficult “pipistrelloid” species. The species of the genus Pipistrellus (sensu Hill and Harrison 1987) are spread over the Pipistrelllni and Vespertilionini. We therefore suggest the splitting of this heterogenous genus into at least four genera. Only the members of the previous subgenus Pipistrellus constitute the genus Pipistrellus and belong to the Pipistrellini. The previous subgenera Hypsugo, Vespadelus and Falsistrellus, given generic rank in some recent studies, belong to the tribe Vespertilionini and are not closely related to Pipistrellus. For the genera Eptesicus and Hesperoptenus, which belong neither to the Vespertilionini nor to the Pipistrellini, the tribe Eptesicini was established. The phylogenetic relations of this tribe and the status of the presumably polyphyletic tribe “Nycticeiini” could not be solved.     

Cytotaxonomy of the apocynaceae

At present there is karyological information on ca 10% of the species and ca 30% of the genera of the Apocynaceae. Basic numbers of x = 6, 8, 9, 10, 11, 12, 16, 18, 20, 21 and 23 have been assessed. Of these x = 11 is primitive, occurring in ca 60% of the genera. Those of x = 6, 8, 9 and 10 have evolved by reduction, and x = 12 by increase from x = 11. In the subtribe Secondatiinae however, x = 12 is most likely the result of doubling x = 6. The numbers x = 16, 18 and 20 are likewise doubles of x = 8, 9 and 10 respectively. Those of x = 21, 23, and in one case, x = 20 are probably aneuploid products of doubles of x = 11. The two larger subfamilies, Plumerioideae and Apocynoideae have the basic numbers x = 8, 9, 10 and 11 in common and are not separable on the basis of chromosomal evidence. The third small subfamily Cerberoideae is more homogeneous according to basic number, i.e. x = 10 and 20. Most genera are characterized by a constant basic number, but some have two basic numbers; these clearly are cases of infrageneric aneuploidy. Based on records in the literature two closely related generaApocynum andTrachomitum appear to be characterized by a basic number of x = 8 as well as x = 11. This conflicting situation should be clarified by further karyological research. From the level of subtribe onwards some taxa have one basic number, but others are characterized by two or more numbers. The occurrence of similar basic numbers in different phylads of the family is considered to be the result of similar chromosomal evolution mechanisms. Approximately 22% of the investigated species are polyploid. Intrageneric polyploidy occurs with a frequency of about 12.5% and infraspecific polyploidy with less than 4%. The karyotypes observed are symmetrical: the chromosomes within a karyotype are similar in length with primary constrictions usually in a median position. In the Tabernaemontaneae however, it was observed that the karyotypes comprise one pair of distinctly heterobrachial chromosomes in addition to the metacentric ones. This tribe is also characterized by chromosomes which are relatively long. Most genera of the African continent, which are well known regarding their chromosome number, are characterized by x = 11. Exceptions areStrophantus (x = 9) with a mainly tropical African distribution. Two other genera with derived numbers, i.e.Gonioma with x = 10 andPachypodium with x = 9, occur in southern Africa and Madagascar. The genera with a non-African distribution are less known for their chromosome number. However, the available evidence suggests that evolution of derived numbers has occurred more frequently outside Africa than on this continent.     

New chromosome counts and evidence of polyploidy in Haageocereus and related genera in tribe Trichocereeae and other tribes of Cactaceae

Chromosome numbers for a total of 54 individuals representing 13 genera and 40 species of Cactaceae, mostly in tribe Trichocereeae, are reported. Five additional taxa examined belong to subfamily Opuntioideae and other tribes of Cactoideae (Browningieae, Pachycereeae, Notocacteae, and Cereeae). Among Trichocereeae, counts for 35 taxa in eight genera are reported, with half of these (17 species) for the genus Haageocereus. These are the first chromosome numbers reported for 36 of the 40 taxa examined, as well as the first counts for the genus Haageocereus. Both diploid and polyploid counts were obtained. Twenty nine species were diploid with 2n=2x=22. Polyploid counts were obtained from the genera Espostoa, Cleistocactus, Haageocereus, and Weberbauerocereus; we detected one triploid (2n=3x=33), nine tetraploids (2n=4x=44), one hexaploid (2n=6x=66), and three octoploids (2n=8x=88). In two cases, different counts were recorded for different individuals of the same species (Espostoa lanata, with 2n=22, 44, and 66; and Weberbauerocereus rauhii, with 2n=44 and 88). These are the first reported polyploid counts for Haageocereus, Cleistocactus, and Espostoa. Our counts support the hypothesis that polyploidy and hybridization have played prominent roles in the evolution of Haageocereus, Weberbauerocereus, and other Trichocereeae.     

Cytotaxonomic observations in tropical Vaccinieae (Ericaceae)

Chromosome numbers are reported for 36 accessions representing 31 species from nine genera of the tribe Vaccinieae, family Ericaceae. The plants are tropical and come from Southeast Asia and Central and South America. The taxonomy of the tribe is outlined in these regions. Genera are often poorly defined and taxa were chosen to reflect the range of variation of the Vaccinieae. Most Southeast Asian Vaccinium species were diploid (2n= 24) as were those of Agapetes subgenus Agapetes (apart from the Himalayan A. flava), Agapetes scortechinii and Costera endertii. All other accessions were found to be polyploid. The correlation between polyploidy, geographical distribution and the possession of an ‘anatomical complex’ of the leaf and stem in Vaccinieae of New Guinea and the neotropics is discussed.     

Cytotaxonomy of cichorieae

The karyotypes of 13 species belonging to six genera of the tribeCichorieae (Compositae) are described. The role of base number variation and polyploidy, associated with structural alterations in speciation has been indicated and discussed. Close, affinities are seen between the members investigated, so that classification under one tribe is, supported on cytological grounds. Some observations on apomixis inTaraxacum are added, and the remarkable adaptability of one cytotype ofTaraxacum in the Himalayas is discussed.     

Molecular phylogenetic analyses of nuclear and plastid DNA sequences support dysploid and polyploid chromosome number changes and reticulate evolution in the diversification of Melampodium (Millerieae, Asteraceae)

Chromosome evolution (including polyploidy, dysploidy, and structural changes) as well as hybridization and introgression are recognized as important aspects in plant speciation. A suitable group for investigating the evolutionary role of chromosome number changes and reticulation is the medium-sized genus Melampodium (Millerieae, Asteraceae), which contains several chromosome base numbers (x = 9, 10, 11, 12, 14) and a number of polyploid species, including putative allopolyploids. A molecular phylogenetic analysis employing both nuclear (ITS) and plastid (matK) DNA sequences, and including all species of the genus, suggests that chromosome base numbers are predictive of evolutionary lineages within Melampodium. Dysploidy, therefore, has clearly been important during evolution of the group. Reticulate evolution is evident with allopolyploids, which prevail over autopolyploids and several of which are confirmed here for the first time, and also (but less often) on the diploid level. Within sect. Melampodium, the complex pattern of bifurcating phylogenetic structure among diploid taxa overlain by reticulate relationships from allopolyploids has non-trivial implications for intrasectional classification.