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We assessed the status of two New Zealand endemic morphodemes in the genus Sticta , currently treated as two separate taxa, Sticta filix and Sticta lacera. Both are green-algal lichens with a distinct stipe that grow in forested habitats and are suitable indicators of the indigenous vegetation health in forest ecosystems in New Zealand. They exhibit different morphologies and substrate ecologies: S. filix forms rather robust thalli, often on exposed trunks of phorophytes, with erect stems distinctly emerging from the substrate, whereas S. lacera is a more delicate lichen growing near the base of trees, usually among bryophyte mats or sheltered in the exposed portions of the phorophyte root-plate, with a prostrate, branched, stolon-like stem barely emerging from the substrate. Throughout their range, both taxa grow sympatrically and often in close proximity (syntopically). Despite the differences, ITS barcoding does not support the two morphodemes as separate species. In this study we assessed two possible explanations: (1) S. filix and S. lacera are discrete phenotypes of a single species, caused by developmental switching triggered by a discrete environmental variable, the propagules developing either on bare substrate or between bryophytes; and (2) the two morphodemes represent separate lineages, but ITS does not provide sufficient resolution to reflect this. We performed a quantitative analysis of morphological and ecological parameters, based on vouchered herbarium collections and field observations on iNaturalist NZ (https://inaturalist.nz), to assess the level of discreteness of the growth forms and to test for a correlation with the presence of a bryophyte mat. We further took advantage of an existing molecular data set from a target capture approach, comprised of 205 protein markers. This data set was used to establish a framework of percentage identities between pairs of the same and of different species among lobarioid Peltigeraceae and then to test whether the S. filix / lacera pairing fell closer to a within-species or a between-species pairing. The morphometric analysis of herbarium material resolved S. filix and S. lacera as two discrete morphs with little overlap, supported by numerous observations on iNaturalist NZ. However, whereas herbarium material suggested a significant association of the lacera morph with bryophyte mats, no such pattern was evident from field images on iNaturalist NZ, in which both morphs frequently associated with bryophyte mats. This highlights the limitations of herbarium material to correctly assess substrate ecology, whereas iNaturalist NZ postings had issues with correct identifications, given that especially S. lacera is easily confused with Pseudocyphellaria multifida. Based on the target capture data, the percentage identity of the S. filix / lacera pairing (99.43%) was significantly higher than that of all 12 between-species pairings (93.20–98.01%); it was at the same time lower than that of all within-species pairings (99.63–99.99%) but significantly so only in comparison with five out of the eight within-species pairings. The target capture approach is thus inconclusive, but the combination of all data suggests that S. filix and S. lacera are not discrete morphodemes of a single species but represent two separate lineages which emerged recently and hence cannot be resolved using the ITS barcoding marker or even a deeper phylogenomic approach based on protein-coding markers. We propose transplantation experiments and the application of RADseq to further assess this situation. [ABSTRACT FROM AUTHOR]

Ocellularia (Graphidaceae) is a genus of crustose lichens comprising c.200 species, four known from Australia and New Zealand. Based on recent collections from northern North Island, we describe a fifth species Ocellularia jacinda-arderniae, which is a member of the O. bicuspidata complex. This complex is characterised by peculiar, appendiculate ascospores and a psoromic acid chemistry. Two further undescribed species of this complex, one from North Island and one from South Island, are discussed but left undescribed pending further study. Based on our findings, we provide a revised assessment of New Zealand Ocellularia. Of the four species included in the most recent Flora of New Zealand Lichens from 2007, three do not belong in that genus and the identification of the fourth is incorrect; instead, the following four taxa are recognised: O. jacinda-arderniae, O. aff. dolichotata, O. aff. bicuspidata (a) (South Island; OTA 58820) and O. aff. bicuspidata (b) (North Island; UNITEC 10818). This leads to the somewhat unusual situation that a presumably known genus biota in New Zealand is entirely replaced by names of a new species and three provisional identifications. The following new combination is introduced: Schizotrema concentricum (Stirt.) Lücking comb. nov. In addition, the name Thelotrema manosporum (C. Knight.) Hellb. is given as the correct name for the New Zealand taxon previously identified as T. monosporum Nyl., and the name T. monosporoides Nyl. [syn.: O. monosporoides (Nyl.) Hale] is established as a taxonomic synonym of T. manosporum, leaving two New Zealand species of Thelotrema with large, brown ascospores, namely T. manosporum and T. saxatile C. Knight. The situation of the genus Ocellularia highlights the need for detailed taxonomic revision of understudied lichen groups in New Zealand, especially as these and related genera in the Graphidaceae are excellent indicators of forest health and can be used for monitoring purposes. [ABSTRACT FROM AUTHOR]

Pyrenula (Pyrenulaceae) is a poorly studied genus of lichenized mycobiota in New Zealand. Following the sampling of lichens from over 50 vegetation plots established within the Auckland Region by the Auckland Council, we have recognised a further five species of Pyrenula: P. leucostoma (Zahlbr.) R. C. Harris, P. microcarpa Müll. Arg., P. pyrenuloides (Mont.) R. C. Harris, P. subumbilicata (C. Knight) Aptroot and P. subvariolosa (C. Knight) Aptroot from the New Zealand Botanical Region. These discoveries increase the number of Pyrenula accepted for New Zealand from 10 to 15, and extend the range of two species previously regarded as endemic to Australia. The discoveries also highlight the importance of undertaking more comprehensive lichen sampling within New Zealand's ecosystems. We recommend that, for those regions where permanent vegetation plots have been established for long-term monitoring, an assessment of lichen diversity should also be included in their initial sampling phase and monitoring protocols. With these additions, as well as changes in the taxonomy of New Zealand Pyrenula, a revised key to the known species of Pyrenula in New Zealand is presented. [ABSTRACT FROM AUTHOR]

Summary: Lichens are an essential component of ecosystem processes. Many lichen species are habitat specialists that rely on specific tree substrates and moisture regimes of old‐growth forests and are not found in early‐successional forests, small isolated forest fragments or restoration projects, making them useful bioindicators of forest health. Pressures from habitat loss and fragmentation have affected the viability and survival of lichen species that are often limited by low dispersal ability. As a rule, lichens are rarely included in ecological restoration programmes despite translocation methods being available. We trialled a combination of two of the more successful methods (gauze packets and use of adhesive gels). Three different gelling agents were used in attempt to immobilize living soredia of the lichen Crocodia aurata on trunks of Ti Kouka/Cabbage Tree (Cordyline australis) for long enough for them to develop into thallus lobes. The effectiveness of these methods was tracked over a 2‐year period. Our results show that all three gel treatments were effective at immobilizing soredia in the gauze packets. Lobe formation occurred in all three gel treatments after 36 weeks, with methyl cellulose the most successful with six packets producing lobes, five Ac‐Di‐Sol® and two agarose packets also producing lobes, out of a possible total 100 gauze packets. Lobe formation was slightly more successful on the south sides of trees (seven of thirteen packets), despite initial survival and vitality of soredia being higher on the north sides of the trees. [ABSTRACT FROM AUTHOR]

Ramalina leiodeaandR. luciaeare reported from mainland New Zealand for the first time. A revised key to theRamalinaof the New Zealand Botanical Region is offered to accommodateR. leiodea, the recently confirmed Kermadec Islands records ofR. microspora, and the reinstatedR. ovalis. [ABSTRACT FROM AUTHOR]

Plants that grow epiphytically are often adapted to hold water in a central cup or in leaf axils to maintain hydration given that they cannot access soil water. These bodies of water, called phytotelmata, are miniature temporary aquatic ecosystems. This water frequently contains a variety of microorganisms. The New Zealand native Collospermum hastatum (Colenso) Skottsb. (Asteliaceae) is known to hold water within the leaf axils; however, an assessment of algal communities within this habitat has never been undertaken. To remedy this lack of knowledge, water samples were obtained from the leaf axils of C. hastatum, with exotic bromeliads for comparison. Freycinetia banksii A.Cunn. and Astelia solandri A.Cunn. were also investigated, but did not contain sufficient water for further investigation. Urban bromeliads investigated had a wide range of organisms within the phytotelmata, including four genera of diatoms. No desmids were identified. Collospermum and Forest-sourced bromeliad water held a comparatively less diverse range of biota, with a complete lack of algal presence. We propose three possible explanations for this; inadequate light levels for algal growth; unsuitable phytotelmic pH; and low background levels of algae for dispersal within native forest environments. [ABSTRACT FROM AUTHOR]