PATTERN,TEMPO, AND MODE OF EVOLUTIONARY AND BIOGEOGRAPHIC DIVERGENCE IN OXYSTYLIS AND WISLIZENIA (CAPPARACEAE)

Six populations of Oxystylis lutea and nine populations representing three subspecies of Wislizenia refracta were analyzed for electrophoretic variation at 18 loci. Several marker alleles differentiate O. lutea from W. refracta, although mean pair-wise genetic identity values (range, 0.53–0.64) are comparable to those found among many congeners. Oxystylis and Wislizenia share two duplicated gene loci that are not present in outgroup species in Cleome and Cleomella. Thus, they appear to be monophyletic sister taxa within a larger monophyletic group. Based on allozyme differentiation patterns, we infer a pre-Pleistocene divergence prior to differentiation within W. refracta. Subsequent anagenesis in the O. lutea lineage and cladogenesis in the W. refracta lineage have resulted in extensive morphological differentiation between Oxystylis and Wislizenia. Therefore, Oxystylis and Wislizenia are phenetically and phylogenetically distinct, and we recognize them as genera. Geographic modes of speciation predominate in the group. Variation patterns within W. refracta are consistent with recognition of three subspecies, and indicate that subsp. californica is not a historical introduction in the Central Valley of California.     

POLYPLOIDY,DYSPLOIDY, AND CHROMOSOME PAIRING IN ECHEVERIA (CRASSULACEAE) AND ITS HYBRIDS

The 140+ species of Echeveria have more than 50 gametic chromosome numbers, including every number from 12 through 34 and polyploids to n = ca. 260. With related genera, they comprise an immense comparium of 200+ species that have been interconnected in cultivation by hybrids. Some species with as many as 34 gametic chromosomes include none that can pair with each other, indicating that they are effectively diploid, but other species with fewer chromosomes test as tetraploids. Most diploid hybrids form multivalents, indicating that many translocations have rearranged segments of the chromosomes. Small, nonessential chromosomal remnants can be lost, lowering the number and suggesting that higher diploid numbers (n = 30–34) in the long dysploid series are older. These same numbers are basic to most other genera in the comparium (Pachyphytum, Graptopetalum, Sedum section Pachysedum), and many diploid intergeneric hybrids show very substantial chromosome pairing. Most polyploid hybrids here are fertile, even where the parents belong to different genera and have very different chromosome numbers. This seems possible only if corresponding chromosomes from a polyploid parent pair with each other preferentially, strong evidence for autopolyploidy. High diploid numbers here may represent old polyploids that have become diploidized by loss, mutation, or suppression of duplicate genes, but other evidence for this is lacking. Most species occur as small populations in unstable habitats in an area with a history of many rapid climatic and geological changes, presenting a model for rapid evolution.     

ON PENTAMPLEXUSSCHINDEWOLF, 1940 (ANTHOZOA,RUGOSA) AND ITS POSSIBLE RELATIVES AND ANALOGUES

Abstract: Three ampleximorphic taxa are revised and their most important characters are discussed in terms of possible or apparent relationships. Re‐interpretation of its early ontogeny allows the assignment of Pentamplexus Schindewolf, 1940 to the family Polycoeliidae de Fromentel, 1861. Stereolasma variabilis Vojnovsky‐Krieger, 1934 is established as the type species of Vojnovskytes gen. nov. It resembles the family Polycoeliidae in some characters and the Antiphyllidae Ilina, 1970 or the Laccophyllidae Grabau, 1928 in others. Thus, its family status is not established. Revision of the type material of Fasciculophyllum tripus Schindewolf, 1952 allows its inclusion within the new genus Silesamplus, probably related to the family Laccophyllidae Grabau, 1928 . Amplexoid morphology is further shown to be inadequate for the establishment of relationships on the family or subfamily level. Early ontogeny is most important in that respect, but biform vs normal morphology in the tabularium and free vs contratingent development of minor septa must also be considered, where appropriate.     

FLORAL ANTHOCYANINS IN SPECIES AND HYBRIDS OF BROUGHTONIA,BRASSAVOLA, AND CATTLEYOPSIS (ORCHIDACEAE)

Chromatographic and spectrophotometric methods were used to identify the floral anthocyanins of Broughtonia domingensis, B. negrilensis, B. sanguinea, Brassotonia ‘John Miller,’ Diabroughtonia, Brassavola nodosa, Cattleyopsis lindenii, and Cattleytonia ‘Rosy Jewell’ for the purpose of establishing chemotaxonomic relationships and inheritance patterns. Flowers of Brassavola nodosa were found to contain raphanusin C, an anthocyanin not present in Cattleyopsis lindenii or in any of the Broughtonia species and hybrids. Pelanin is present in flowers of Broughtonia domingensis and B. negrilensis, but not in those of B. sanguinea. Raphanusin B, raphanusin D, and pelargonidin-3-glucoside, 5-sophoroside which are present in B. sanguinea were also found in its intergeneric hybrids with Diacrium and Brassavola. These findings suggest that Cattleyopsis lindenii should not be transferred to Broughtonia and that B. domingensis, B. negrilensis, and B. sanguinea are separate species.     

广西百色和永乐盆地的始新世猪类化石──兼论早期猪类的分类和演化(英文)

描述了广西百色及永乐盆地发现的中始新世最晚期一晚始新世的猪类化石。这批已知最早的猪超科化石,大大丰富了亚洲地区的早期猪类,对了解全球猪类的早期演化有着重要价值。广西的材料被确定为两个新属新种：萨氏始新猪Ｅｏｃｅｎｃｈｏｅｒｕｓ ｓａｖａｇｅｉ和广西华夏猪Ｈｕａｘｉａｃｈｏｅｒｕｓ ｇｕａｎｇｘｉｅｎｓｉｓ,一个新种：粗壮暹罗猪Ｓｉａｍｏｃｈｏｅｒｕｓ　ｖｉｒｉｏｓｕｓ和一个未定属种：Ｔａｙａｓｓｕｉｄａｅ　ｇｅｎ．ｅｔ　ｓｐ．ｉｎｄｅｔ。加上已发表的单尖旅猪Ｏｄｉｏｃｈｏｅｒｕｓ　ｕｎｉｃｏｎｕｓ,百色、永乐盆地共计发现了５种始新世猪类化石。新属Ｅｏｃｅｎｃｈｏｅｒｕｓ虽然臼齿结构简单,与原始的古猪类（ｐａｉａｅｏｃｈｏｅｒｉｄ）接近,但因其Ｍ３具有一个明显的跟座而被归入猪科。早期猪科动物非常原始的臼齿形式证明,猪科动物的起源并不晚于古猪科（Ｐａｌａｅｏｃｈｏｅｒｉｄａｅ）和西科（Ｔａｙａｓｓｕｉｄａｅ）。旧大陆的古猪类长期以来被认为与新大陆的西类（ｔａｙａｓｓｕｉｄ）更为接近,多数学者将其归入西科。笔者认为两者共有的近祖特征,并不能支持它们更近的亲缘关系,而且古猪类缺乏典型西类的近裔特征,因而支持将Ｐａｌａ?     

PLASTID MORPHOLOGY,ULTRASTRUCTURE, AND DEVELOPMENT IN COLACIUM AND THE LORICATE EUGLENOPHYTES (EUGLENOPHYCEAE)1

Chloroplast morphology was investigated in five species of euglenophytes: Trachelomonas volvocinopsis Swirenko, Strombomonas verrucosa (Daday) Deflandre, Strombomonas costata Deflandre, Colacium mucronatum Bourrelly et Chafaud, and Colacium vesiculosum Ehrenberg. All five species share a common plastid morphotype: disk‐shaped plastids with a pyrenoid that protrudes asymmetrically toward the center of the cell and is capped by a single large grain of paramylon that conforms to the shape of the pyrenoid. Although plastids demonstrated some degree of diversity among the species studied, it was not consistent with current generic boundaries. The plastids of S. verrucosa show a developmental pattern similar to that of Euglena gracilis. The plastids divide during the early portion of the light phase after cell division, and pyrenoids are reduced or absent in dividing plastids. Developmental patterns of plastid replication also suggest that these five taxa share recent common ancestry with members of the genus Euglena subgenus Calliglena.     

金绒花天牛与金丝花天牛的鉴定及分布(鞘翅目,天牛科,花天牛亚科,花天牛族)(英文)

金丝花天牛Leptura aurosericans Fairmaire,1895广泛分布在中国南方与东南亚地区,而金绒花天牛Leptura auratopilosa(Matsushita,1931)仅分布于台湾岛。最近10年,国内在金绒花天牛与金丝花天牛的鉴定及分布记录方面出现了一些不一致的报道。为了澄清这些问题,在核对模式标本及检视系列标本(包括许多正在自然交配的成对标本)的基础上,重新描述了这两个种的形态特征,给出了这两个种的鉴别特征并提供了彩色照片,认为金绒花天牛是台湾特有种,目前在大陆尚未发现。     

CHROMOSOMES,HYBRIDS AND PLOIDY OF SEDUM CREMNOPHILA AND ECHEVERIA LINGUIFOLIA (CRASSULACEAE)

Sedum cremnophila and Echeveria linguifolia have generally been placed in different genera on the basis of their flowers—largely because the petals are spreading in one and erect in the other—and the genera have been placed in different subfamilies. However, they are very similar vegetatively and in their unusual inflorescence, their karyotypes are similar (n = 33), and they readily hybridize to produce fertile F₁ hybrids. Study of hybrids of these two species with numerous others leads to the conclusion that each of the two is effectively diploid, with a genome consisting of 33 chromosomes that are all different and that do not pair with each other. Therefore, the good chromosome pairing and the fertility of the hybrid between them are the result of close structural and genetic homology between the corresponding chromosomes of the two species. Taxonomic revision to reflect their very close relationship is desirable. Some other species of Sedum and Echeveria also may need to be reclassified.     

DNA,RNA, AND PROTEIN COMPARISONS BETWEEN NODULATED AND NON-NODULATED MALE-STERILE AND MALE-FERTILE GENOTYPES OF SOYBEAN (GLYCINE MAX L.)

Four soybean (Glycine max L. Merr.) lines isogenic except for loci controlling male sterility (ms₁) and nodulation (rj₁) were developed to study the effects of reproductive development and nitrogen source on the nucleic acid and protein levels within the leaves. Changes in DNA, RNA, protein, and cellular viability were measured from flowering (77 days after emergence) until maturity (147 days after emergence) in leaves of nodulated and non-nodulated male-sterile and fertile soybean genotypes. Leaf nuclei from the sterile genotypes yielded DNA amounts that were significantly higher than those from the fertile lines. The average DNA values for the nodulated sterile and nodulated fertile lines at 147 days after emergence were 7.01 and 2.45 picograms, respectively. The average 2C DNA amount as determined from dividing root-tip nuclei was 2.83 picograms, which indicated occurrence of endopolyploid mechanisms in the sterile lines and age-related loss of DNA in fertile lines. Similar to DNA findings, the RNA and protein values in the sterile lines were significantly higher than those values observed in the fertile lines, suggesting an increased capacity to synthesize protein. The soybean leaf nuclear DNA declined, especially in the fertile lines in terms of the percent endopolyploid nuclei as well as the average DNA content during maturation. The DNA decline in leaves of fertile genotypes suggests that the leaves may be exporting nucleosides and phosphates to the seeds during embryo formation. In the sterile lines, due to the reduced pod-set, these ready reserves of nucleosides and phosphates tended to accumulate in the chromatin of the leaf nucleus as manifested by the DNA specific Feulgen stain. By the end of the study (147 days after emergence), the nodulated fertile genotypes had experienced a dramatic loss in DNA, RNA, and protein. The nodulated sterile genotypes, however, indicated 65% more DNA, 59% more RNA, and 53% more protein as compared to the nodulated fertile genotypes at 147 days after emergence. The sterile lines also indicated the slowest increase in the death of cells, while the fertile lines indicated the fastest increase in nonviable cells, as shown by trypan blue staining. The fertile lines displayed normal monocarpic senescence throughout the study. The reproductive structures of fertile plants utilized the molecules in seed production, whereas in the sterile lines, these accumulated in leaf cells.     

MORPHOLOGY, ANATOMY AND HISTOLOGY OF FLABELLINA AFFINIS (GMELIN, 1791) (NUDIBRANCHIA, AEOLIDOIDEA, FLABELLINIDAE) AND ITS RELATION TO OTHER MEDITERRANEAN FLABELLINA SPECIES

The Atlantic and Mediterranean flabellinid Flabellina affinis(Gmelin, 1791) (Opisthobranchia, Nudi-branchia, Aeolidoidea)is examined morphologically, anatomically and histologicallywith special emphasis on characters which have been widely neglectedin recent literature (e.g. the histological structure of theoral glands, typhlosole). The study provides detailed data aboutall organ systems which are compared to existing data of otherauthors. The species described as Flabellina affinis by Bergh(1875; 1886) is considered not to be conspecific with the Flabellinaaffinis examined in this and other studies. Furthermore, Flabellinaaffinis is compared to other Mediterranean species, especiallyF. ischitana (Hirano & Thompson, 1990). F. ischitana differsfrom F. affinis mainly by the structure of the genital system.The phylogenetic trees presented for the genus by Gosliner &Kuzirian (1990) and Gosliner & Willan (1991) are discussed. (Received 5 August 1996; accepted 9 June 1997)     

(D)- AND (L)-CYCLOHEXENYL-G,A NEW CLASS OF ANTIVIRAL AGENTS: SYNTHESIS,CONFORMATIONAL ANALYSIS,MOLECULAR MODELING,AND BIOLOGICAL ACTIVITY

(D)- and (L)-cyclohexeneyl-G were synthesized enantioselectively starting from (R)-carvone. Both show potent and selective anti-herpesvirus activity (HSV-1, HSV-2, VZV, CMV). Molecular modeling demonstrates that both isomers are bound in the active site of HSV-1 thymidine kinase in a high-energy conformation with the base moiety orienting in an equatorial position. It is believed that the flexibility of the cyclohexene ring is essential for their antivirial activity.     

SPORE MORPHOLOGY OF ANEMIA,MOHRIA, AND CERATOPTERIS (FILICALES)

Spores of the ferns Anemia and Mohria (Schizaeaceae) and Ceratopteris (Pteridaceae) are surveyed with light microscopy and scanning and transmission electron microscopy. In each genus the spores are trilete with radially symmetrical exine sculpture comprising three sets of parallel or near-parallel muri. Anemia has six spore types. One is reticulate (A. wrightii-type), and the other five types have either cicatricose or canaliculate sculpture that reflect a basic form, i.e., three mural sets that have mutual anastomoses in each radial region. The cicatricose A. mexicana- and the canaliculate A. dregeana-types represent the simplest expressions of this pattern. Specializations include cicatricose, auriculate (A. raddiana-type) and canaliculate, ornate (A. oblongifolia-, A. phyllitidis-types). Exine structure is homogeneous or differentially microporate; the enveloping two-layered perine has granulate structure and a granulate to spiculate and/or pitted surface. Mohria spores have a stratified, granulate to rugulose perine and cicatricose exine sculpturing consistent with the A. mexicana-type pattern, but the muri are hollow. The canaliculate spores of Ceratopteris differ from those of Anemia and Mohria in that the three mural sets are discrete and separated from each other by a stria in each radial region; exine structure is homogeneous and the thin perine is granulate. Within Anemia the A. raddiana-type is exclusive to subgen. Coptophyllum and the A. oblongifolia- and A. phyllitidis-types to subgen. Anemia. Three spore types are shared by two subgenera; i.e., A. wrightii- and A. mexicana-types in Coptophyllum and Anemirhiza, and the A. dregeana-type in Anemirhiza and Anemia. Spore polymorphism is indicated in several species of subgen. Anemia, and smooth immature spores are recorded from all three subgenera.