Isoenzyme polymorphism in the genus Thermopsis

Minimal variation in the leucine aminopeptidase and indophenol oxidase isoenzyme patterns in the genus Thermopsis is reported. Two closely related legume genera. Baptisia and Thermopsis, are compared with respect to isoenzyme variation in natural populations. Observed differences suggest that isoenzyme polymorphism may be a useful measure of evolutionary vitality.     

Phenolic acids in the genus Lycopodium

The dihydric phenolics from the leaves of 170 Ecuadorian Lycopodium specimens representing 49 species and varieties have been examined as semiquinones by EPR spectroscopy. An ester of dihydrocaffeic acid was observed in 137 extractors of specimens all confined to the subgenus Urostachya. The ester was not present in the subgenera Lycopodium and Lycopodiella, where the dominant phenolic acid was chlorogenic acid. The concentrations of the “Urostachyaester” were found to increase with increasing altitude. Hydroquinone and protochatechuic acid have been observed in a few specimens.     

Flavonoid variation in the genus briza

During a survey of 6 Eurasian and 10 South American Briza species for leaf flavonoids, 27 components were found. Twelve of these were identified: tricin 5-glucoside, tricin 7-glucoside, quercetin 3-glucoside, kaempferol 3-glucoside, vitexin, isovitexin, orientin, iso-orientin, and the 4′-O-glucoside of all 4 glycoflavones, 3 of which are reported for the first time. The Eurasian species, with the exception of Briza maxima, are remarkably uniform in their flavonoid pattern, accumulating mainly vitexin and isovitexin; whereas the South American species are characterized by the presence of orientin, iso-orientin and 9 unidentified flavonoids. In Briza media and the South American species, ploidy level is shown to play a large part in flavonoid variation. Examination of 12 diploid and 8 autotetraploid plants of B. media revealed that diploids accumulate vitexin and isovitexin, whereas tetraploids accumulate orientin and iso-orientin, autotetraploidy having apparently upset regulatory genes in the formation of the flavone C-glycosides. Mild alkaline treatment of both isovitexin and iso-orientin was found to give 100% conversion to the corresponding 8-C-glucoside.     

Systematics of the genus Floridichthys

Samples representing the three nominal subspecies of Floridichthys carpio were examined electrophoretically. Although the populations in Florida could not be distinguished completely from the populations in Yucatan by morphology, 5 of the 30 electrophoretic characters demonstrated fixed differences between Florida and Yucatan populations. Based on the observed genetic differentiation between Florida and Yucatan populations and the absence of genetic differentiation within those populations, we conclude that the Yucatan population has diverged to the species level. We, therefore, propose to elevate the nominal Yucatan subspecies Floridichthys carpio polyommus to a species status.     

Distribution of alditols in the genus Bostrychia

Several species of the red algal genus Bostrychia were investigated for the presence of low-molecular weight carbohydrates constituting their specific assimilate pattern. All species were found to contain remarkable amounts of two hexitols, dulcitol and sorbitol. The results are discussed with emphasis on the chemotaxonomic implications.     

Occurrence of Nosema oryzaephili in Cryptolestes ferrugineus and transfer to the genus Paranosema

A microsporidium that closely resembles Paranosema species at the level of the light microscope was isolated from the rusty grain beetle, Cryptolestes ferrugineus. It’s identity as Nosema oryzaephili (originally described from Oryzaephilus surinamensis) was confirmed by comparison with a known isolate of N. oryzaephili based on spore size, small subunit rDNA sequence, and relative infectivity to O. surinamensis, Tribolium castaneum, and Ephestia kuehniella. Phylogenetic analysis of the small subunit rDNA indicates clearly that this species belongs in the genus Paranosema and thus the designation Paranosema oryzaephili (Burges, Canning and Hurst) is proposed. In spite of the abundance, economic importance, and world-wide distribution of C. ferrugineus, this is the first report of a microsporidial infection in this species. This is also the first report of P. oryzaephili in the new world.     

Alkaloid chemotaxonomy of the genus Sophora

Cytisine and matrine alkaloids detected in Sophora species have been used to classify the genus chemotaxonomically.     

A review of the genus Paraphyllanthoxylon

Thirteen species of petrified wood have been assigned previously to the genus Paraphyllanthoxylon which was established by Bailey (1924) as representative of the section Phyllanthoideae of the family Euphorbiaceae. Mädel (1962) considered the genus Paraphyllanthoxylon representative of only the Glochidion wood group of the section Phyllanthoideae. This necessitates the establishment of a new genus, Phyllanthoideoxylon, for fossil woods which have characteristics in common with several of the other wood groups in the section Phyllanthoideae. The thirteen previously identified species of Paraphyllanthoxylon are reviewed and compared with the characteristics of the genus. Eleven of these species are retained in Paraphyllanthoxylon Bailey (emend. Mädel), one (P. bangalamodense) is assigned to Phyllanthoideoxylon nov. gen. and one (P. keriense) is transferred to Bridelioxylon Ramanujam.     

Isoflavonoid phytoalexins of the genus Medicago

Detached leaves of 25 annual and perennial Medicago species have been inoculated with the fungus, Helminthosporium carbonum, and examined for subsequent production of isoflavonoid phytoalexins. Hydroxylated pterocarpan (medicarpin) and isoflavan (vestitol, sativan and isosativan) phytoalexins were obtained from most of the species investigated. Although large quantities of two flavonoid derivatives, isoliquiritigenin and liquiritigenin, were isolated from leaves of M. lupulina, this species was apparently unable to produce isoflavonoid compounds. Traces of 7-hydroxy-2′,4′-dimethoxyisoflavanone (a substance not previously recorded in the tribe Trifolieae) were obtained (together with medicarpin, vestitol and sativan) from M. sativa cv Du Puits. Some taxonomic aspects of phytoalexin induction are discussed with reference to the generic location of certain controversial Medicago species including M. (Trigonella) radiata.     

A rediagnosis of the genus Australopithecus

A rediagnosis of the genus Australopithecus has become desirable because of the recent increase of both cranial and post cranial specimens, and new analyses of functional morphology. The diagnosis proposed here builds on previous diagnoses through the addition of new criteria and the reemphasis of certain features already known to characterize the genus.     

Distribution of exudate flavonoids in the genus Plectranthus

Thirty-four species of the genus Plectranthus (including species of the former genera Coleus and Solenostemon, fam. Lamiaceae) were surveyed for exudate flavonoids to see whether the distribution of these compounds would support a recent classification of the genus based on molecular and morphological characters. In this classification two major groups had been identified, the Coleus and Plectranthus clades. Only about 40% of the species, predominantly from the Plectranthus clade, were found to produce exudate flavonoids, which were mainly flavones. Flavanones were restricted to five species of the Plectranthus clade, whereas flavonols were only found in two species of the Coleus clade, Plectranthus montanus Benth. (synonyms Plectranthus marrubioides Hochst. ex Benth. and Plectranthus cylindraceus Hochst. ex Benth.) and Plectranthus pseudomarrubioides R.H.Willemse. Four of these flavonols were isolated from P. montanus and identified by NMR spectroscopy as the 3,7-dimethyl ether and 3,7,4′-trimethyl ether of quercetin and the 3,6,7-trimethyl ether and 3,6,7,4′-tetramethyl ether of quercetagetin. The remaining flavonols and flavones were identified by HPLC–UV and LC–MS of crude extracts on the basis of their UV and mass spectra, retention times and comparison with standards. Most flavonols were 3-methyl ethers and many of the flavones and flavonols were oxygenated at the 6-position. The most common flavones, occurring in both clades, were cirsimaritin and salvigenin, which are methoxylated at the 6- and 7-positions. 6-Hydroxylated flavones such as scutellarein and ladanein were restricted to species of the Plectranthus clade.     

Systematics and evolution of the genus Torrubiella (Hypocreales, Ascomycota)

Torrubiella is a genus of arthropod-pathogenic fungi that primarily attacks spiders and scale insects. Based on the morphology of the perithecia, asci, and ascospores, it is classified in Clavicipitaceae s. lat. (Hypocreales), and is considered a close relative of Cordyceps s. 1., which was recently reclassified into three families (Clavicipitaceae s. str., Cordycipitaceae, Ophiocordycipitaceae) and four genera (Cordyceps s. str, Elaphocordyceps, Metacordyceps, and Ophiocordyceps). Torrubiella is distinguished morphologically from Cordyceps s. lat. mainly by the production of superficial perithecia and the absence of a well-developed stipitate stroma. To test and refine evolutionary hypotheses regarding the placement of Torrubiella and its relationship to Cordyceps s. lat., a multi-gene phylogeny was constructed by conducting ML and Bayesian analyses. The monophyly of Torrubiella was rejected by these analyses with species of the genus present in Clavicipitaceae, Cordycipitaceae, and Ophiocordycipitaceae, and often intermixed among species of Cordyceps s. lat. The morphological characters traditionally used to define the genus are, therefore, not phylogenetically informative, with the stipitate stromata being gained and/or lost several times among clavicipitaceous fungi. Two new genera (Conoideocrella, Orbiocrella) are proposed to accommodate two separate lineages of torrubielloid fungi in the Clavicipitaceae s. str. In addition, one species is reclassified in Cordyceps s. str. and three are reclassified in Ophiocordyceps. The phylogenetic importance of anamorphic genera, host affiliation, and stipitate stromata is discussed.     

Flavonoid pigments of butterflies in the genus Melanargia

Flavonoid pigments (18) were identified in the wings and body of Melanargia galathea: tricin, tricin 7-glucoside, tricin 7-diglucoside, tricin 4′-glucoside, luteolin, luteolin 7-glucoside, luteolin 7-diglucoside, luteolin 7-triglucoside, apigenin, apigenin 7-glucoside, orientin, orientin 7-glucoside, iso-orientin, iso-orientin 7-glucoside, vitexin 7-glucoside, vitexin 7-glucoside, isovitexin, isovitexin 7-glucoside and a novel but incompletely identified tricin 4′-conjugate. Examination of the wings and bodies of individual M. galathea, M. galathea var. procida, M. lachesis, M. russiae, M. larissa, M. occitanica and M. ines butterflies from a number of different populations in Europe by 2D PC revealed that variation in their flavonoid patterns was so minor that the flavonoid pattern of these Melanargia spp. may be considered constant. The concentration of flavonoids in the wings of each butterfly was greater than that in the body, as is the covering of scales. Not all flavonoids are located in the scales; some are also located in the reproductive tissues of the female. With the exception of the tricin 4′-conjugate which was absent from the egg and first instar larvae before feeding commences, these flavonoids were present in all the life stages of M. galathea. The presence of tricin 4′-conjugate in Melanargia but its absence from the larval food plants suggests that this compound is synthesized by the insect and that flavonoids are not merely sequestered from the diet but are also partly metabolized.     

Zopfochytrium is a new genus in the Chytridiales with distinct zoospore ultrastructure

While surveying chytrid diversity in lakes and streams, we found on cellulosic bait a chytrid that had both monocentric and polycentric thallus forms. We brought this chytrid into axenic culture from three sites in eastern North America, studied its thallus development and zoospore ultrastructure, and compared its 28S rDNA sequence with those of other members of the Chytridiomycota. Thallus morphology matched that described for the rare chytrid, Cladochytrium polystomum Zopf. Sporangia were spherical and produced numerous long discharge tubes. After discharge, zoospores remained in spherical clusters at the tips of the inoperculate openings of discharge tubes. After 10–30 min zoospores either swam away or encysted in place. Zoospore ultrastructural features included a cell coat, flagellar plug, and paracrystalline inclusion, features typical of members of the Chytridiales. However, the flagellar apparatus structure and organellar organization differed from that of zoospores previously described. Based on its molecular phylogeny and its zoospore ultrastructural features, we classify C. polystomum as a member of the Chytridiaceae in the Chytridiales. Because its thallus development and its ribosomal DNA sequences diverged decidedly from those of Cladochytrium tenue Nowak, the type species of Cladochytrium, we erected Zopfochytrium as a new genus for this chytrid.     

Cytogenetic study of complex hybrids in the genus Lemur (Primates Prosimians)

A cytogenetic study was carried out of several Lemur hybrids and their progeny. The effects of Robertsonian translocations in the heterozygous state on fertility and the possibility of a preferential transmission of metacentric trivalents are debated.     

Multilocus sequence analysis of the genus Bradyrhizobium

The use of multilocus sequence analysis (MLSA) for the taxonomy of Bradyrhizobium was assessed. We compared partial sequences for atpD, recA, gyrB, rpoB and dnaK for a set of reference strains representing named species and genospecies, and a number of new isolates from Lupinus albus, Arachis hypogaea and Ornithopus compressus from Spain. The phylogenies of the individual genes were compared with previous DNA–DNA hybridization results. High hybridization values were well reflected, but intermediary hybridization values were less clearly apparent. However, the phylogeny of a concatenated dataset of the five genes did reflect all values and thus is more informative of overall genome similarity. Our results indicate that only for the genes gyrB, rpoB and dnaK there is a small gap between the interspecies sequence similarities and the intraspecies similarity, and therefore cut-off levels for species delineation cannot be set, although high sequence similarity (>99%) does permit identification. In a few instances, a reference strain did not group as expected for one of the five genes tested. This may be a result of horizontal gene transfer and recombination events occasionally involving housekeeping genes. This observation indicates it is best to consider more than one gene for taxonomic inferences. The majority of the new isolates from the three host species was identified as Bradyrhizobium canariense. Four strains from L. albus from León, Spain, formed a separate group close to Bradyrhizobium japonicum.     

Entomopathogenic species of the hyphomycete genus Tolypocladium

Two entomopathogenic species of the hyphomycete genus Tolypocladium are described in detail. Tolypocladium extinguens sp. nov. was found on larvae of Arachnocampa luminosa (Diptera; Mycetophilidae) in caves in New Zealand. Tolypocladium cylindrosporum W. Gams is shown to be pathogenic to Aedes sierrensis and A. australis and is reported from Plecia nearctica (Diptera; Bibionidae). The occurrence of entomopathogenic species in this normally soil-borne genus is discussed.