Taxonomic revision of water-bloom-forming species of oscillatorioid cyanobacteria

A polyphasic approach was used to clarify the taxonomy of the water-bloom-forming oscillatorioid cyanobacteria. Seventy-five strains of oscillatorioid cyanobacteria were characterized by 16S rDNA sequence analysis, DNA base composition, DNA-DNA hybridization, fatty acid composition, phycobilin pigment composition, complementary chromatic adaptation, morphological characters, growth temperature and salinity tolerance. Phylogenetic analysis based on 165 rDNA sequences divided the strains into six groups, all of which were clearly separated from the type species of the genus Oscillatoria, Oscillatoria princeps Gomont NIVA CYA 150. Therefore, these strains should be classified into genera other than Oscillatoria. Groups I-III were closely related to one another and groups IV-VI were distinct from one another and from groups I to III. Group I was further divided into two subgroups, group I-pc, which includes strains containing only phycocyanin (PC), and group I-pe, which includes strains containing large amounts of phycoerythrin (PE) in addition to PC. This phenotypic distinction was supported by DNA-DNA hybridization studies. Based on the properties examined herein and data from traditional, botanical taxonomic studies, the groups and subgroups were classified into single species and we propose either emended or new taxonomic descriptions for Planktothrix agardhii (type strain NIES 204(T)), Planktothrix rubescens (type strain CCAP 1459/22(T)) Planktothrix pseudagardhii sp. nov. (type strain T1-8-4(T)), Planktothrix mougeotii (type strain TR1-5(T)), Planktothricoides raciborskii gen. nov., comb. nov. (type strain NIES 207(T)), Tychonema bourrellyi (type strain CCAP 1459/11B(T)) and Limnothrix redekei (type strain NIVA CYA 277/1(T)).

Taxonomic studies of parasitic nyctotherans from chinese Anura amphibians III. Wichtermania

Wu-Han Xiao, Jian-Guo Wang and Lian-Xiang Li (2002) Taxonomic studies of parasitic nyctotherans from Chinese Anura amphibians III. Wichtermania. Zoological Studies 41(1): 69-76. This paper describes 6 new species belonging to the genus Wichtermania from Anura amphibians distributed in southern China. The 6 species are Wichtermania multigranularis sp. nov., W. oviformis sp. nov., W vesiformis sp. nov., W. reticulatis sp. nov., W granuliformis sp. nov., and W obliquoides sp. nov. The characteristics for diagnosis of the 6 new species are described in this paper.

Taxonomic studies of parasitic nyctotherans from chinese Anura amphibians IV. Spirocytopharynxa gen. nov and Macrocytopharynxa gen. nov.

Lian-Xiang U, Jian-Guo Wang and Wu-Han Xiao (2002) Taxonomic studies of parasitic nyctotherans from Chinese Anura amphibians IV. Spirocytopharynxa gen. nov. and Macrocytopharynxa gen. nov. Zoological Studies 41(1): 77-84. This paper describes 2 new genera and 5 new species of nyctotherans from Anura amphibians distributed in southern China. Based on the composition of the upper and bottom flaps, the number and position of sutural lines, the length of the oral groove, and the morphology and position of the end of the cytopharynx, the adoral zone of the membranelle (AZM), and the macronucleus, two new genera were established. The 3 new species, Spirocytopharynxa sinensis, S. guangxiensis, and S. quadranus, belong to the new genus Spirocytopharynxa, Another 2 species, Macrocytopharynxa (Nyctotheroidae Nie, 1932) pyriformis n. comb. and M. lingchuanensis n. sp., belong to the new genus Macrocytopharynxa. The characteristics for diagnosis of the 2 new genera and 5 new species are described in this paper.

Taxonomic re-evaluation of Aphanizomenon flos-aquae NH-5 based on morphology and 16S rRNA gene sequences

The taxonomy of Aphanizomenon flos-aquae strain NH-5, a producer of cyanotoxins, was re-evaluated by comparison with six other Aphanizomenon strains using morphological characteristics and 16S rRNA gene sequences. Strain NH-5 was concluded to be improperly identified as Aph. flos-aquae based upon (1) lack of bundle formation in the trichomes, (2) location of akinetes next to heterocytes, (3) lower similarities (less than 97.5%) in the 16S rRNA gene sequences relative to Aph. flos-aquae strains, and (4) comparison within a phylogenetic tree constructed from 16S rRNA gene sequences. The Aphanizomenon strains investigated in this study are classified to four morphological groups as described by the classical taxonomy of Komarek & Kovacik (1989). This classification was supported from the phylogenetic results of 16S rRNA gene sequences. This study also discusses the generic boundaries between Aphanizomenon and Anabaena.

Inland free-living nematodes in China: A historical review of taxonomic studies with descriptions of Aphanonchus orientalis sp nov (Chromadorida : Leptolaimidae) and Daptonema limnobia sp nov (Monhysterida : Xyalidae)

The study of inland free-living nematodes is relatively imperfect in China, only seventeen papers were previously published. Since the early researches in 20-30s, few works have been accomplished until 80s. Altogether 171 taxa were formerly recorded, among which, over eighty species have been re-combined. A checklist of the former records with notes on their distribution is presented in this paper. Recently, the function of free-living nematodes has received much attention from Chinese zoologists. Hence, the present authors carried out their studies with emphasis on taxonomy of inland nematodes. During the survey of freshwater lakes, two species are found to be nem to science. Aphanonchus orientalis sp. nov. is characterized by having sclerotized vagina, the presence of 10-11 tubular supplements and 42-62 alveoli supplements in males, but no alveoli in females. Daptonema limnobia sp, nov. is distinguished from other species of the genus in the presence of larger and more anteriorly located amphids, shorter bifurcated spicules, smaller apophysis of gubernaculum, shorter terminal setae, and postvulval uterine sac in females.

Characterization of a homogeneous taxonomic group of marine magnetotactic cocci within a low tide zone in the China Sea

Magnetotactic bacteria are a heterologous group of motile prokaryotes, ubiquitous in aquatic habitats and cosmopolitan in distribution. Here, we studied the diversity of magnetotactic bacteria in a seawater pond within an intertidal zone at Huiquan Bay in the China Sea. The pond is composed of a permanently submerged part and a low tide subregion. The magnetotactic bacteria collected from the permanently submerged part display diversity in morphology and taxonomy. In contrast, we found a virtually homogenous population of ovoid-coccoid magnetotactic bacteria in the low tide subregion of the pond. They were bilophotrichously flagellated and exhibited polar magnetotactic behaviour. Almost all cells contained two chains of magnetosomes composed of magnetite crystals. Intriguingly, the combination of restriction fragment length polymorphism analysis (RFLP) and sequencing of cloned 16S rDNA genes from the low tide subregion samples as well as fluorescence in situ hybridization (FISH) revealed the presence of a homogenous population. Moreover, phylogenetic analysis indicated that the Qingdao Huiquan low tide magnetotactic bacteria belong to a new genus affiliated with the alpha-subclass of Proteobacteria. This finding suggests the adaptation of the magnetotactic bacterial population to the marine tide.

Taxonomic study on the family Mitridae (Mollusca : Gastropoda : Neogastropoda) from the China's Seas. Subfamilies: Imbricariinae and Cylindromitrinae

Ninteen species of subfamilies Imbricariinae and Cylindromitrinae, family Mitridae, are recorded from the China's seas. Of which, one genus and six species are recorded for the first time from China's seas, i.e., genus Ziba Adams H and Adams A, Cancilla (Cancilla) carnicolor, Ziba duplilirata, Z. insculpta, Neocancilla circula, Scabricola (Scabricola) desetangsii, Scabricola (Swainsonia) ocellata ocellata.

On the taxonomic system of Eurasian Pamphagidae (Orthoptera: Caelifera)

This paper provides a new taxonomic system for the Eurasian Pamphagidae, in which the 47 known genera are divided into 6 subfamilies including 4 new subfamilies: Prionotropisinae nov., Thrinchinae, Pamphaginae, Tropidaucheninae nov., Nocarodesinae nov., Orchaminae nov.

Karyomorphology of Biebersteinia Stephan (Geraniaceae) and its systematic and taxonomic significance

The systematic and taxonomic position of Biebersteinia Stephan has long been in dispute. The present paper describes for the first time the karyomorphology of two species in Biebersteinia Stephan. Both species commonly showed the interphase nuclei of the simple chromocenter type and the mitotic prophase chromosomes of the interstitial type. The karyotype formulae of both B. heterostemon and B. odora were 2n=10=2m(2sec)+8sm(2sec), belonging to the 3A type of Stebbins' classification. The karyotype of this genus is recorded for the first time. The basic chromosome numbers of four of the five known species of Biebersteinia have been recorded as x=5. The combination of resting nuclei of the simple chromocenter type, mitotic prophase chromosomes of the interstitial type, two pairs of chromosomes with four obvious secondary constrictions at the mitotic prophase and metaphase stages, and the peculiar 3A karyotype in Biebersteinia can be regarded as the karymorphological marker of this genus. The karyomorphological data presented here do not support the traditional grouping of this genus in Geraniaceae. The unique karyomorphology of Biebersteinia justifies its familiar or ordinal status, which is congruent with embryological, anatomical, chemical and molecular data. The systematic position of Biebersteinia needs further study.

Taxonomic Syntax for First-Order Inference

Most knowledge representation languages are based on classes and taxonomic relationships between classes. Taxonomic hierarchies without defaults or exceptions are semantically equivalent to a collection of formulas in first order predicate calculus. Although designers of knowledge representation languages often express an intuitive feeling that there must be some advantage to representing facts as taxonomic relationships rather than first order formulas, there are few, if any, technical results supporting this intuition. We attempt to remedy this situation by presenting a taxonomic syntax for first order predicate calculus and a series of theorems that support the claim that taxonomic syntax is superior to classical syntax.