New finding of Vaucheria aversa Hassall (Ochrophyta, Xanthophyceae) in Ukraine

Vaucheria aversa (Xanthophyta) was recorded for the first time in Ukraine in Sula River, Hydrological Reserve «Artopolot», Poltava Region. It was found in benthos in spring (May 2020) in silty-sandy soil in shallow water. The material was collected and processed according to a common methodology. Sterile samples before the appearance of the gametengians were kept in natural water in petri dishes in well-lit places. This method of «coarse culture», in most cases, allowed to get gametangia within two weeks. The species identification was done with fertile filaments only. 4% formaldehyde solution was used for material fixation. Taxonomic identification of samples was done using a comparative and morphological methods, which includes analysis of morphological variability and verification of the consistency of the studied material with the diagnosis. Thalli of V. aversa are direct, branched, bisexual, 80–90 μm wide. Antheridia are cylindrical, tubular shape, pressed to the filament or slightly raised above it, 119–130 × 41–43 μm. Oogonia erect, sessile, ovoid to subspherical, sometimes placed in pairs, with a curved beak at the front, 190–230 × 140–163 μm. According to morphological characteristics this species is similar to another one from section Tubligerae Walz – V. fontinalis (Linnaeus) T.A. Christensen. Their distinctive and common features are as follows. Filaments of V. fontinalis are narrower (up to 75 μm) than V. aversa (up to 131 μm). Both species are characterized by oogonia grouped together in a row. Antheridia present in quantity 1 or 2 on both sides of oogonia. But the species are very different in size and shape of oogonia: in V. aversa they are sessile, located one at a time or less often two, extended near the base, sharply narrowed at the apex. The beak is directed straight or obliquely up, bent to the side of the oogonia body. In V. fontinalis oogonia are placed in one row, most often in the amount of 1-6, the beak tapers gradually. Anteridia are cylindrical, on short pedicel. V. aversa grew as a part of polyspecies complex of green algae together with representatives of such genera as Cladophora Kützing, Spirogyra Link and Mougeotia C. Agardh. V. aversa is widely distributed in continental water bodies of Europe, Asia and North America, Australia and New Zealand, but is firstly recorded in Ukraine.

Wicklowia submersa sp. nov. (Wicklowiaceae, Pleosporales), a second species in a monotypic family

A new freshwater ascomycetous species, Wicklowia submersa was found on submerged wood in a freshwater stream in Krabi Province in southern Thailand. This is a second species in a monotypic family. Morphological examination and phylogenetic analysis of LSU and SSU sequence data support this new species as belonging to Wicklowia in the family Wicklowiaceae (Pleosporales). Wicklowia submersa possesses ascomata that are immersed, erumpent when mature, raised and visible as dark oval or slit-like structures on host surface. The bitunicate asci have well-developed ocular chambers when immature with a short pedicel. Ascospores are ellipsoidal-oblong, asymmetrical, 1-septate, guttulate when immature, hyaline, with a distinctly mucilaginous sheath. The characteristics of the asci, and ascospores which lack both apical and basal appendages distinguish it from the type species W. aquatic. A description, illustration and comparison of the new species is provided. The risk of introducing monotypic families is discussed.

Phylogeny and taxonomy of Habenaria leprieurii, H. alpestris and H. sect. Microdactylae (Orchidaceae), with descriptions of two new taxa

Habenaria leprieurii and H. alpestris both have histories of misleading and conflicting taxonomic identifications. We investigated the taxonomy, phylogenetic relationships, and sectional classification of those and related species. Examinations of type specimens and large numbers of additional live and herborized samples revealed that H. schwackei, H. amazonica, and H. platydactyla are conspecific with H. leprieurii and are characterized by having a white corolla and a long pedicel. The species previously treated as H. leprieurii, is H. cruegerii, of which H. culmiformis is a synonym and are characterized by the green flowers, short pedicel and the straight ovary, parallel to the inflorescence axis, curved only in the apex. A species from central-western Brazil, previously treated as H. alpestris, corresponds to a new species, described here as H. omissa, while H. alpestris is conspecific with H. melanopoda. We propose a new circumscription for H. sect. microdactylae, including H. leprieurii, H. heptadactyla, H. cruegerii, and the newly described H. omissa and H. cruegeri var. flaviflora—which now form a morphologically homogeneous section. An identification key, plus descriptions, notes, illustrations, and lists of specimens for each species are presented.

A new species of Palaeocarya (Juglandaceae) from the Ningming Basin in Guangxi, South China

A new species of fossil winged fruits of Palaeocarya (Juglandaceae) is recognized from the Oligocene Ningming Formation in Guangxi, South China. The fruits of Palaeocarya huashanensis sp. nov. consist of a trilobate wing with an oblong median lobe, pinnate and eucamptodromous lobe venation, a hispid nutlet, and a very short pedicel. This new species, along with other four species reported previously from the same locality, represents the Oligocene Palaeocarya occurrence in the lowest latitude and provides additional evidence of diversity of Juglandaceae in the Paleogene in South China, and new data for the investigation of the origin and evolution of the tribe Engelhardieae.

A new species of Chrysophyllum (Sapotaceae) from the Brazilian Atlantic forest

The new species Chrysophyllum pubipetalum from the Brazilian Atlantic forest of Espírito Santo state is described and illustrated. This new species is characterized by the presence of trichomes on both surfaces of the corolla (a character unique in the genus), channeled petioles, a relatively short pedicel length, and various characters of the fruits and seeds. A distribution map and a table distinguishing the new species from morphologically similar species are also included. As based on IUCN criteria, the species is considered critically endangered.

Calvatia guzmanii sp. nov. (Agaricaceae, Basidiomycota) from Paraná State, Brazil

A new species of Calvatia is described from a semideciduous seasonal forest fragment in the western region of Paraná State, southern Brazil. Calvatia guzmanii is proposed as new based on the combination of dark brown and spiny to velvety exoperidium, prominent subgleba and echinulate-reticulate basidiospores with a short pedicel. A comparison with morphologically similar Calvatia species is giv

First Report of Phytophthora palmivora Causing Root Rot of Cassava in China

Cassava (Manihot esculenta) is an economically important crop grown widely in South China. Seventy percent of the cassava grown is used for starch and ethanol production and it has become the foundation of local food and bioenergy systems. In November 2010, a new root rot disease was found on cv. HuaNan205 from a cassava plantation in Danzhou, Hainan Province. Disease occurred on 30% or less of the plants. Initially, the upper leaves wilted at noon and recovered in the evening. Eventually, infected plants no longer recovered and the whole plant wilted and died. Root rot symptoms consisting of irregular brown patches occurred on the tuberous roots. Symptomatic root rot tissue was cut into 1-cm pieces, washed in distilled water, and soaked in a solution of 1% sodium hypochlorite for 3 min. A subsection was cut from each sterilized piece, placed on a plate of V8 agar medium, and incubated at 28°C for 7 days. Pathogenicity was established by following Koch's postulates. In July 2011, 10 plants of cassava cv. HuaNan205 were selected from a disease-free plantation in Danzhou. The pathogen was cultivated on V8 agar at 28°C for 14 days. Four holes were established 15 cm from the base of the cassava plants. Five plants were inoculated with 100 mL of the mycelial suspension in each of the four spots and covered by soil. The other five plants were treated with sterile water as control. Plants were maintained for 4 months. All five of the inoculated plants wilted and two died, while the control plants grew normally. Symptoms similar to the original root lesions were observed on tuberous roots of inoculated plants, while only scars formed on tuberous roots of control plants. The pathogen was reisolated from the lesions of inoculated plants. Microscopic examination showed the sporangia as papillate and ovoid with the widest part close to the base. They were easily washed off and each detached sporangium contained a short pedicel 1.2 to 6.9 μm long, average 2.9 μm. Chlamydospores were readily observed on diseased roots and observed in pure cultures on V8 agar. Morphological characteristics of the specimen were similar to the descriptions for Phytophthora palmivora (2). Genomic DNA of this isolate was extracted with a cetyltrimethylammoniumbromide protocol (3) from mycelium and used as a template for amplification of the internal transcribed spacer (ITS) region of rDNA with primer pair ITS1/ITS4 (1). The sequence (GenBank Accession No. HE580279) exactly matched several sequences (e.g., GenBank Accession Nos. HQ237481.1, AY745750, and AY745751) of P. palmivora. To our knowledge, this is the first report of root rot caused by P. palmivora on cassava in China. References: (1) D. E. L. Cooke et al. Fungal Genet. Biol. 30:17, 2000. (2) D. C. Erwin and O. K. Ribeiro. Phytophthora Diseases Worldwide. The American Phytopathological Society, St. Paul, MN, 1996. (3) J. R. Xu et al. Genetics 143:175, 1996.

Review of the systematics, morphology and distribution of Malagasy dwarf geckos, genera Lygodactylus and Microscalabotes (Squamata: Gekkonidae)

The Malagasy species of the dwarf gecko genera Lygodactylus Gray and Microscalabotes Boulenger have been largely neglected in recent studies on the herpetofauna of Madagascar. Since the historically earliest taxonomic description of Lygodactylus tolampyae in 1872, studies have mainly dealt with the systematics of these lizards, yet many taxonomic issues and the validity of several species is unclear. Some species have been described on the basis of immature specimens, or based on a low specimen number from single sites, and there are no assessments of geographic variation. In this paper we provide a review of Malagasy Lygodactylus and Microscalabotes based on preserved material from a number of major natural history museums, including types of most species, and on own collections. For each species we provide morphological diagnoses, standardized descriptions of up to 24 morphological characters, a list of localities, and discussions of geographical variation if it was apparent from the specimens examined. All except three Malagasy Lygodactylus species are assigned to a total of four phenetic species groups of which at least some may also represent monophyletic units. Hemipenial morphology is described for 11 species and provides a valuable source of characters to distinguish species groups, especially the L. madagascariensis group that differs from other Malagasy species by their lack of hemipenial serrated ridges with pointed papillae, short pedicel and poorly defined lobes. Lygodactylus praecox Pasteur, 1995 is considered as a junior synonym of Lygodactylus klemmeri Pasteur, 1964. One new species, Lygodactylus roavolana, is described based on a unique combination of morphological characters.

First Report of Phytophthora Stem Rot on Gloxinia in Bulgaria

Severe stem base necrosis was observed on potted gloxinia (Sinningia speciosa) plants in a greenhouse in the Plovdiv Region of Bulgaria in the spring of 2006 and sporadically in 2007. Initial symptoms were water-soaked lesions at the stem base; eventually the lesions spread upward and downward until the entire stem was affected, resulting in withered leaves and plant collapse. Disease foci were sometimes apparent in rows of plants because of water splash. White, fungal-like colonies with arachnoid, aerial mycelia were obtained from affected plant tissue placed on potato dextrose agar (PDA) at 24 to 25°C in the dark. Pyriform to ellipsoid sporangia, 30 to 55 × 23 to 40 μm (average 38 × 27 μm), with a prominent papilla (sometimes two) and a short pedicel were observed. Chlamydospores were intercalary or terminal, spherical, and 15 to 55 μm in diameter. Oogonia and antheridia were not observed. On the basis of morphological features, the pathogen was tentatively identified as Phytophthora nicotianae (2). Pathogenicity was tested by placing 3-mm-diameter discs from 7-day-old PDA cultures onto wounded petioles of visibly healthy 3-month-old gloxinia potted plants (three replicates). Sterile PDA plugs were placed onto similar wounds of three control plants. The inoculated wounds were covered with Parafilm. Three days after inoculation, water-soaked lesions began to spread longitudinally in both directions on inoculated petioles. The pathogen was recovered from the inoculated tissue but not from the control plants. Molecular identification of the pathogen was achieved with PCR-restriction fragment length polymorphism of the internal transcribed spacer regions ITS1 and ITS2 of the ribosomal DNA (1). The restriction patterns obtained with the enzymes AluI, MspI, and TaqIα were identical to those of P. nicotianae, confirming the morphological identification. To our knowledge, this is the first report of P. nicotianae on gloxinia in Bulgaria. References: (1) D. E. L. Cooke and J. M. Duncan. Mycol. Res. 101:667, 1997. (2) D. C. Erwin and O. K. Ribeiro. Phytophthora Diseases Worldwide. The American Phytopathological Society, St. Paul, MN, 1996.

First Report of Stalk Rot Caused by Phytophthora tentaculata on Aucklandia lappa in China

Phytophthora tentaculata causes root and stalk rot of Chrysanthemum spp., Delphinium ajacis, and Verbena spp. in nurseries in the Netherlands and Germany (2). In later years, P. tentaculata was isolated from Verbena hybrids (3) and lavender cotton (Santolina chamaecyparissus) in Spain (1). In August 2007, stalk rot symptoms were observed on Aucklandia lappa (Asteraceae), an economically important Chinese medicinal plant, in some fields in Yunnan Province of China. Small groups of infected plants were randomly distributed throughout the fields. Plants showing stalk rot and wilting died rapidly. Diseased tissues were cut into 10-mm pieces and plated onto Phytophthora selective medium, P5ARP (2), to obtain the pure cultures. Seven isolates were obtained, and five isolates were grown on solidified LBA (60 g of lima bean powder and 15 g of agar per 10,000 ml of distilled water) and 10% V8 juice liquid medium for examination of morphological and physiological characteristics (4). The colony surface texture was uniform and formed sparse, loosely branched mycelium on LBA medium. Radial growth rate was 2 to 3 mm per day at 24°C on LBA. In water, relatively small swellings were formed at hyphal branches. Sporangia were spherical or ovoid to obpyriform and some were distorted and papillate with a narrow exit pore. Approximately 10% of the sporangia were caducous with a short pedicel. Sporangial dimensions were 28 to 47 (35) × 21 to 36 (29) μm, length/breadth ratio 1.2. Chlamydospores formed on LBA after 1 week and were terminal, spherical, thin walled, and 21 to 31 (27) μm in diameter. The isolates were homothallic. Oogonia abundantly formed on LBA and were 25 to 36 (31) μm in diameter. One or two paragynous antheridia (15 × 10 μm) were attached to the oogonia. Oospores were spherical, hyaline, aplerotic, and 20 to 32 (25) μm in diameter. The minimum temperature for mycelium growth was 8°C and maximum temperature was 34°C. The internal transcribed spacer (ITS) region was amplified and sequenced and agreed 100% with sequences of four P. tentaculata isolates deposited in GenBank (Accession Nos. AJ854302, AY881001, DQ335634, and AF266775). Pathogenicity was assessed by flooding three potted A. lappa plants with a 104 ml–1 zoospore suspension and incubating at 20 to 22°C. As controls, two potted A. lappa plants were flooded with deionized water. All three inoculated A. lappa plants exhibited stalk rot after 15 days, from which the pathogen was reisolated using selective medium, P5ARP. Controls remained healthy 15 days after inoculation, To our knowledge, this is the first report of P. tetaculata H. Kroeber & R. Marwitz infection of A. lappa in China. We speculate that the pathogen might have been introduced from other countries on seeds. References: (1) L. A. Álvarez et al. Plant Dis. 90:523, 2006. (2) D. C. Erwin and O. K. Ribeiro. Phytophthora Diseases Worldwide. The American Phytopathological Society, St. Paul, MN, 1996. (3) E. Moralejo et al. Plant Pathol. 53:806. 2004. (4) X. B. Zheng. Methods in Phytophthora. Chinese Agriculture Press, Beijing, China, 1995.