Host Thallus Research Articles

Macroepiphyte biodiversity on Kappaphycus alvarezii surface and its interaction with environment in cultivation centers on Lombok Island, Indonesia

Abstract. Ghazali M, Widoretno W, Arumingtyas EL, Retnaningdyah C. 2022. Macroepiphyte biodiversity on Kappaphycus alvarezii surface and its interaction with environment in cultivation centers on Lombok Island, Indonesia. Biodiversitas 23: 6284-6292. The aims of this paper are to investigate the influence of environmental factors on the diversity of macroepiphytes in Kappaphycus alvarezii. Macroepiphyte sampling was carried out at four cultivation centers: Seriwe Bay, Ekas Bay, Gerupuk Bay, and Siwak of Lombok Island, West Nusa Tenggara, Indonesia. Several stations were placed at each location, and at each station were used one to three cultivation units with five replications. Environmental data measurements were carried out at the time of sampling. Some parameters were measured: pH, temperature, salinity, current velocity, brightness, DO, BOD, nitrate, phosphate, and TSS. Data analysis was performed using several diversity indices. In addition, a biplot analysis was performed using PCA to analyze the correlation between environmental factors and environmental factors to macroepiphytes. The results showed that the most dominant species was Polysiphonia spaerocharpa, and the second was Ceramium sp1. The highest richness and abundance were found in Ekas Bay. The highest species dominance was in Siwak. The highest diversity index was in Ekas Bay. The correlation between environmental factors showed that hemeroby harmed depth, phosphate, and DO and positively affected BOD and the thallus surface structure. The principal correlation analysis showed that the abundance of macroepiphyte was influenced by BOD, the roughness of host thallus, and the hemeroby index.

Easy Removal of Epiphytic Bacteria on Ulva (Ulvophyceae, Chlorophyta) by Vortex with Silica Sands.

Macroalgae-associated bacteria play an important role in their algal hosts’ biological processes. They are localized on surfaces of the host thalli, as well as between and even within algal cells. To examine the differences in community structures and functions between epi- and endo- bacteria, an effective approach for maximizing epiphyte removal from delicate seaweeds while retaining endophyte fidelity must be developed. In this study, a variety of surface sterilization methods for Ulva prolifera were compared, including mechanical, chemical, and enzymatical treatments. According to the results of scanning electron microscope (SEM) and denaturing gradient gel electrophoresis (DGGE) analysis, almost complete removal of epiphytic bacteria on Ulva was obtained simply by co-vortex of seaweeds with silica sands, causing minimal disturbance to endosymbionts when compared to previous published methods. In addition, the adaptability was also confirmed in additional U. prolifera strains and Ulva species with blade-like or narrow tubular thallus shapes. This easy mechanical method would enable the analysis of community composition and host specificity for Ulva-associated epi- and endo-bacteria separately.

Studies on lichenicolous fungi in the Uppsala (UPS) collection curated by the late Rolf Santesson

Zhurbenko, M. P. 2021. Studies on lichenicolous fungi in the Uppsala (UPS) collection curated by the late Rolf Santesson. – Herzogia 34: 493 –507. A new genus and species, Stromatoneolamya ugandensis, is described for a lichenicolous ascomycete growing on Canoparmelia nairobiensis that mainly differs from Neolamya peltigerae in its well-developed clypeus, completely immersed ascomata clustered in stromatic warts on the host thallus, and the absence of external periphyses. Three additional new species are described: Lichenopeltella mobergii (on Hypogymnia kiboensis), Llimoniella bryonthae (on Pertusaria bryontha), and Plectocarpon santessonii (on Parmotrema pseudonilgherrense). Polycoccum laursenii is reported as new to the southern hemisphere from Australia, Lettauia hypotrachynae new to Uganda, Merismatium corae new to Guatemala, Scutula miliaris new to China, and Stigmidium triebeliae new to Portugal from Madeira. Lettauia hypotrachynae is first reported from Hypotrachyna densirhizinata and Muellerella lichenicola from Pertusaria papillulata.

Two New Species of Lichenicolous Fungus Sclerococcum (Dactylosporaceae, Sclerococcales) from India

Two new species ofSclerococcum, viz.S. dendriscostictaeandS. physciae, colonising members ofDendriscosticta, PhysciaandSticta, are described from Uttarakhand and Andhra Pradesh states of India, respectively.S. dendriscostictaecolonising the host thallus as well as apothecial disc ofDendriscostictaandStictaspecies is generally characterised by its small sized (0.1–0.4 mm) black apothecia, hyaline hymenium, paraphyses without dark apical caps, asci 8-spored, ascospores ellipsoid, hyaline at immature stage and brown at maturity, 1-septate, smooth walled, 9–10–11(–12) × (3–)3.8–5–6.1(–7) µm, whileS. physciaecolonising thallus ofPhysciasp. is characterised by black, rounded to irregular sporodochia (40–100 µm diam.) having ellipsoid or angular, medium to dark brown, mostly simple, rarely 1-septate conidia [(5–)7.5–10–11.7(–14) × (4–)4.7–5.8–6.9(–7) µm]. A key to known Indian taxa is also being provided.

Two New Lichenicolous Species of Opegrapha (Arthoniales) from Canada

Two new species of lichenicolous Opegrapha are described from New Brunswick, Canada. Opegrapha inconspicua was found once on a rock bluff above a river on the thallus of Verrucaria aethiobola. It is characterized by punctiform, rounded, black ascomata 75–170 µm diam., an excipulum dark brown to black only in the upper part and (1–)2(–3)-septate ascospores of (12.5–)15.5–25 × 4–5 (–5.5) µm. Opegrapha parmeliiperda was found in four localities on epiphytic Parmelia squarrosa and P. sulcata. It is characterized by short lirelliform ascomata 70–220(–250) × 70–120 µm, in ± loose groups of 5–15(–20) lirellae forming on black necrotic areas on the host thallus, 4-spored asci of 32–40 × 11–15 µm, and persistently hyaline and 3-septate ascospores of (11–)13–15.5(–17) × (3.5–)4–5(–5.5) µm. Opegrapha lamyi is reported for the first time in Canada, and O. anomea and O. sphaerophoricola for the first time in New Brunswick. One of only two previous reports of O. lamyi for the U.S.A. is based on a specimen from Colorado, revised here to Sclerococcum suburceolatum, the latter record representing a significant range extension for that species. Three of the five lichenicolous Opegrapha species reported here for New Brunswick are so far known in the province only in old mixedwood swamp-forests, highlighting the conservation significance of this forest community type. An identification key to the lichenicolous Opegrapha s.l. species known from Canada is provided. The worldwide diversity and host specificity of lichenicolous Opegrapha s.l. are discussed.

Epiphytic diatoms on Gelidiales (Rhodophyta) from Gran Canaria (Spain)

ABSTRACT The composition and patterns of spatial and season variability of epiphytic diatom assemblages of five intertidal species of Gelidiales (Rhodophyta) from three sampling sites off Gran Canaria (Canary Islands, Atlantic Ocean) were investigated during summer (2007) and winter (2008) seasons using scanning electron microscopy (SEM). Dominant species included Cocconeis scutellum var. scutellum, C. scutellum var. posidoniae, Grammatophora oceanica, Lichmophora eherembergi, Navicula sp. and Tabularia fasciculata and these represented 78% of the total diatom assemblage on Gelidiales. Eight of the diatom taxa, Cocconeis maxima, Amphicocconeis debesii, Cocconeis convexa, C. neothumensis var. marina, C. scutellum var. scutellum, C. scutellum var. posidoniae, Gomphonemopsis obscura and Pseudohimantidium pacificum, found in the present study represent new records for the Canary Archipelago. These species showed two distinct patterns of zonation, one in relation to their position at the intertidal area and the other relative to position on the host thalli. Although the vertical distribution of host thalli at the intertidal zone was important when considering the assemblage structure of epiphytic diatoms, the results showed that the cell abundance distribution changed more significantly when considering season rather than spatial distribution. Moreover, even though morphology of host thalli was not a determining factor, their aggregation mode had a significant influence on the abundance and distribution of microalgae. Finally, considering the growth forms of diatom communities, adnate diatoms were more abundant in turf than in clump species.

Gyrophthorus perforans, a Genus and Species of Lichenicolous Fungi New to North America

Gyrophthorus perforans, previously known as a parasite on Umbilicaria vellea and U. hirsuta in Spain and Italy, is reported from Washington state in the Columbia River Gorge, where it was found infesting Umbilicaria phaea. The blistering infections make the host thallus resemble Umbilicaria subg. Lasallia. Historical records of Lasallia from the Pacific Northwest were checked for Gyrophthorus and found to be misidentifications of other Umbilicaria species, but additional records of Gyrophthorus were not found. Lasallia pensylvanica is confirmed from Alaska and British Columbia along with a single historic location in California, but has not yet been found in Oregon or Washington. Western North American Umbilicaria specimens with blistered surfaces should be checked for the parasite Gyrophthorus before assuming they belong to Umbilicaria subg. Lasallia.

Paranectria affinis . [Descriptions of Fungi and Bacteria

Abstract A description is provided for Paranectria affinis . The material examined for shows that the host ( Ephebe lanata ) thallus is to some extent degraded, and P. affinis may be a relatively broad-spectrum necrotrophic parasite. Some information on its habitat, dispersal and transmission, and conservation status is given, along with details of its geographical distribution (South America, (Brazil (Pernambuco)) Australasia (New Zealand), Europe (France, Norway, Spain, Sweden, UK)). No evaluation has been made of any possible positive economic impact of this fungus (e.g. as a recycler, as a source of useful products, as a provider of checks and balances within its ecosystem, etc.). Also, no reports of negative economic impacts have been found.

Ultrastructure of early stages of Rozella allomycis (Cryptomycota) infection of its host, Allomyces macrogynus (Blastocladiomycota)

This study reconstructs early stages of Rozella allomycis endoparasitic infection of its host, Allomyces macrogynus. Young thalli of A. macrogynus were inoculated with suspensions of R. allomycis zoospores and allowed to develop for 120 h. Infected thalli at intervals were fixed for electron microscopy and observed. Zoospores were attracted to host thalli, encysted on their surfaces, and penetrated their walls with an infection tube. The parasite cyst discharged its protoplast through an infection tube, which invaginated the host plasma membrane. The host plasma membrane then surrounded the parasite protoplast and formed a compartment confining it inside host cytoplasm. The earliest host-parasite interface within host cytoplasm consisted of two membranes, the outer layer the host plasma membrane and the inner layer the parasite plasma membrane. At first a wide space separated the two membranes and no material was observed within this space. Later, as the endoparasite thallus expanded within the compartment, the two membranes became closely appressed. As the endoparasite thallus continued to enlarge, the interface developed into three membrane layers. Thus, host plasma membrane surrounded the parasite protoplast initially without the parasite having to pierce the host plasma membrane for entry. Significantly, host-derived membrane was at the interface throughout development.

Enterographa confusa sp. nov. (Roccellaceae, Arthoniales) discovered by chance in type material of its host lichen Arthonia ochraceella, described more than a century ago

Enterographa confusa is described as new to science from Cuba. It is characterized by a lichenicolous habit, punctiform ascomata immersed in the host thallus, (6–)8-spored asci and 3-septate ascospores of 17–23 × (2.5–)3 µm with a distinct gelatinous sheath of 1.5(–2) µm. The new species was discovered by chance in the thallus of type material of Arthonia ochraceella, which is lectotypified here. A detailed description of this latter is also provided. Enterographa confusa can be easily overlooked because of its tiny pale ascomata similar in colour to those of its host lichen. A key to all lichenicolous Enterographa species is presented.

Octosporopsis erinacea and Octospora kelabitiana (Pezizales) – two new hepaticolous ascomycetes from Borneo

Two new hepaticolous ascomycetes from the Kelabit Highlands (Sarawak, Borneo) are described and illustrated. Both of them infect thallose liverworts growing in damp and shaded localities. Octosporopsis erinacea parasitizing Dumortiera hirsuta (Marchantiopsida) has tiny, light yellow, rimless, setose apothecia, usually 8-spored asci and ellipsoid ascospores. Hyphae with appressoria develop superficially on, and intracellularly within, the host thallus. Dumortiera was recorded as a host for any bryophilous fungus for the first time. Octospora kelabitiana parasitizes species of the genus Riccardia (Jungermanniopsida). It is characterised by very small, light orange, setose apothecia, 8-spored asci, ellipsoid, biguttulate spores and very thick hyphae with conspicuous warts and ridges. Generic placement of both species was inferred based on DNA analysis of two nuclear loci (EF1α, LSU rDNA).

ITS1 metabarcoding highlights low specificity of lichen mycobiomes at a local scale.

As self-supporting and long-living symbiotic structures, lichens provide a habitat for many other organisms beside the traditionally considered lichen symbionts-the myco- and the photobionts. The lichen-inhabiting fungi either develop diagnostic phenotypes or occur asymptomatically. Because the degree of specificity towards the lichen host is poorly known, we studied the diversity of these fungi among neighbouring lichens on rocks in an alpine habitat. Using a sequencing metabarcoding approach, we show that lichen mycobiomes clearly reflect the overlap of multiple ecological sets of taxa, which differ in their trophic association with lichen thalli. The lack of specificity to the lichen mycobiome is further supported by the lack of community structure observed using clustering and ordination methods. The communities encountered across samples largely result from the subsampling of a shared species pool, in which we identify three major ecological components: (i) a generalist environmental pool, (ii) a lichenicolous/endolichenic pool and (iii) a pool of transient species. These taxa majorly belong to the fungal classes Dothideomycetes, Eurotiomycetes and Tremellomycetes with close relatives in adjacent ecological niches. We found no significant evidence that the phenotypically recognized lichenicolous fungi influence the occurrence of the other asymptomatic fungi in the host thalli. We claim that lichens work as suboptimal habitats or as a complex spore and mycelium bank, which modulate and allow the regeneration of local fungal communities. By performing an approach that minimizes ambiguities in the taxonomic assignments of fungi, we present how lichen mycobiomes are also suitable targets for improving bioinformatic analyses of fungal metabarcoding.

Maullinia braseltonii sp. nov. (Rhizaria, Phytomyxea, Phagomyxida): A Cyst-forming Parasite of the Bull Kelp Durvillaea spp. (Stramenopila, Phaeophyceae, Fucales)

Phytomyxea are obligate endoparasites of angiosperm plants and Stramenopiles characterised by a complex life cycle. Here Maullinia braseltonii sp. nov., an obligate parasite infecting the bull kelp Durvillaea (Phaeophyceae, Fucales) from the South-Eastern Pacific (Central Chile and Chiloe Island) and South-Western Atlantic (Falkland Islands, UK) is described. M. braseltonii causes distinct hypertrophies (galls) on the host thalli making it easily identifiable in the field. Sequence comparisons based on the partial 18S and the partial 18S-5.8S-28S regions confirmed its placement within the order Phagomyxida (Phytomyxea, Rhizaria), as a sister species of the marine parasite Maullinia ectocarpii, which is also a parasite of brown algae. The development of resting spores in M. braseltonii is described by light and electron microscopy and confirmed by FISH experiments, which visually showed the differential expression of the 28S non-coding gene, strongly in early plasmodia and weakly in late cysts. M. braseltonii is, so far, the only phytomyxean parasite of brown algae for which the formation of resting spores has been reported, and which is widely distributed in Durvillaea stocks from the Southeastern Pacific and Southwestern Atlantic.

Spatial and temporal variation in algal epiphyte distribution on Ulva sp. (Ulvales, Chlorophyta) from northern Patagonia in Argentina

:In this study of northern Patagonia in Argentina, we examined the annual cycle of the epiphyte composition and abundance on Ulva sp. with respect to intertidal elevation, season and position on host. We found spatial segregation in most environmental gradients. Local environmental conditions, intertidal levels, seasons and portion of host thalli had specific patterns of algal epiphytic community. The host population exhibited seasonality and differential morphological attributes according to the intertidal elevation. Thalli of Ulva sp. had the highest maximum diameters and were heavier in spring and summer at the upper elevation. Epiphytes were more abundant growing on host thalli at middle elevations. Epiphytic Dinophyceae, Chlorophyceae and Cyanophyceae presented clear seasonality. Epiphyte abundances were related to periods with high seawater temperature, long days and high radiation. Lyngbya sp., Cocconeis sp., Navicula spp., Rhabdonema arcuatum, Stylonema alsidii and Myrionema strangulans had the highest frequency. The highest epiphyte abundance was observed in holdfasts, with M. strangulans having the highest frequency and cover. These results are relevant to commercial aquaculture ventures for food and feed sources and application in bioremediation.

Melaspilea tucumana, a new gall-forming lichenicolous fungus from the tropical Andes in Bolivia

AbstractThe new obligately lichenicolous fungus, Melaspilea tucumana Flakus, Etayo & Kukwa, inhabiting thalli of saxicolous Pertusaria s. lat. is described from Tucumano-Boliviano vegetation in Bolivia. The species is characterized by the gall formation and superficial, lirelliform to branched, aggregated apothecioid ascomata with widely exposed discs. The ascomata of M. tucumana are initially perithecioid and immersed in the host thallus, but become superficial and apothecioid when mature, and thus resemble the genus Buelliella. This may suggest the placement of the new species in Dothideomycetes.

Niesslia echinoides (Niessliaceae, Ascomycota), a new lichenicolous fungus on Erioderma from Bolivia

AbstractNiesslia echinoides Etayo, Flakus & Kukwa sp. nov. is described from Bolivia from the corticolous thallus of Erioderma barbellatum. The fungus is characterized by large ascospores usually breaking into halves within the asci, strongly setose and aggregated ascomata, usually simple setae, and no damage caused to the host thallus.

Epiphytism in a subtidal natural bed of Gracilaria gracilis of southwestern Atlantic coast (Chubut, Argentina)

The diversity of epiphytes, their temporal abundance variation and the anatomical structure of host–epiphyte interfaces were studied in the agarophyte Gracilaria gracilis from a natural bed in Bahia Bustamante, Chubut Province, Argentina. Twenty-nine algal species were recorded as epiphytes during 2 years of monthly sampling (March 2006–February 2008). Total epiphyte density ranged between 0.037 ind. cm−2 (November 2006) and 39.37 ind. cm−2 (April 2007), with higher density values throughout the second sampling year. Ceramiales species were the most abundant epiphytes. The density of Ceramium rubrum ranged from 0.09 ind. cm−2 (52 % of the total amount) in September 2006 to 17.4 ind. cm−2 (44.18 % of the total amount) in April 2007. Epiphyte infection was more dependent on spore recruitment and sporeling development, especially on thalli derived from fragmentation, than on seasonal environmental variations. The different infections were analysed, taking into account the epiphytic attachment strength and invasiveness and the degree of damage inflicted on the host. Calothrix confervicola was one of the most abundant species. This epiphyte, weakly attached to the host surface, generated no host tissue damage. In contrast, C. rubrum, Polysiphonia abscissa and other Ceramiales were the species that caused more damage to the host because their rhizoids penetrated the cortical portion of the host thallus, sometimes reaching the medullary tissue. Some generalisations and characterisations of the different epiphyte groups in relation to their consequences to Gracilaria spp. are presented.

Unique distribution of epiphytic Neosiphonia harveyi (Rhodomelaceae, Rhodophyta) along sargassacean hosts

SUMMARYAlthough epiphytism is generally heaviest on older portions of the host thallus and both variation and abundance of epiphytes decrease with proximity to meristematic apices, Neosiphonia harveyi (Bailey) Kim, Choi, Guiry and Saunders was frequently found on upper parts of sargassacean hosts. This study compared density, thallus length and fertility of epiphytic N. harveyi among different regions of Sargassum patens C. Agardh thalli to reveal a unique distribution pattern of this epiphyte. The majority of epiphytic N. harveyi was observed on the upper part of host thalli and was seldom seen near the basal part. Over a 3‐month period, mean epiphyte density was greater on host apices while thallus length and fertility were greater on subapical portions of host thalli, suggesting the colonization by this epiphyte near the apical part of the host. Distribution patterns of this epiphyte were similar among S. patens growing at different depths. Apical portions of S. patens appear to be more suitable substrata for N. harveyi settlement and colonization compared with other portions of the host thallus, regardless of depth.

Epiphytic relationships ofPseudendoclonium submarinumWille (Ulvophyceae) andRhodymenia pseudopalmata(Rhodophyta) from the Patagonian coast of Argentina

SUMMARYThe occurrence of the epiphyte algaPseudendoclonium submarinumWille (Ulvophyceae) onRhodymenia pseudopalmata(Lamouroux) Silva (Rhodophyta) is reported. The present study describes a first line of evidence of an epidemiological study conducted with the purpose of comparing both the prevalence and effects of algal epiphytic organisms inR. pseudopalmatain the Patagonian coasts of Argentina.P. submarinuminfected approximately 80% ofR. pseudopalmatathalli and the frequency of infection was variable in connection with different areas of the host's thalli: 42% ofR. pseudopalmatafronds presentedP. submarinumthalli in the basal region, which presented a severity degree of infection from low to high. The median region presented an average frequency of infection of 30% and minor susceptibility to colonization. The covering varied from 1% to 70% representing a low to moderate degree of colonization. The apical region presented a cover frequency of 28% and the level of infection varied between low to moderate. The developmental morphology and the growth dynamics of the epiphyte were also investigated under unialgal as well as bialgal culture conditions. In nature, thalli ofP. submarinumonR. pseudopalmatanever invaded internal tissues of the host. Vegetative thalli ofP. submarinumwere inoculated on frondsR. pseudopalmata. Experimental infections confirmed thatP. submarinumthalli did not penetrate the host's fronds.P. submarinumswarmers showed the capacity of settlement on a host's fronds and developed an epiphytic monostromatic thallus. The results allowed us to suggest thatP. submarinumuses theR. pseudopalmatathalli as a proper substrate, sincePseudendocloniumthalli complete the entire life cycle. Culture experiments revealed thatP. submarinumcould develop without the presence of the host and evidenced the nutritional independence, being the relationship in nature, probably triggered by an ecological advantage since fronds ofR. pseudopalmataoffer a suitable substratum.

Lichenostigma svandae, a new lichenicolous fungus on Acarospora cervina

Abstract:The new species Lichenostigma svandae is described. It is known exclusively from Acarospora cervina, where it forms black stromatic hyphal strands and black sack-shaped ascomata on the host thallus surface. It is similar to L. elongatum and L. rouxii, but differs in a few characters. A short overview of the known Lichenostigma species is provided.