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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]

We present a phylogenetic revision of the Sticta filix morphodeme in New Zealand. This nonmonophyletic group of early diverging clades in the genus Sticta is characterized by a stalked thallus with a green primary photobiont and the frequent formation of a dendriscocauloid cyanomorph. Traditionally, three species have been distinguished in New Zealand: S. filix (Sw.) Nyl., S. lacera (Hook. f. & Taylor)Müll. Arg. and S. latifrons A. Rich., with two cyanomorphs separated under the names Dendriscocaulon dendriothamnodes Dughi ex D. J. Galloway (traditionally associated with S. latifrons) and D. dendroides (Nyl.) R. Sant. ex H. Magn. (traditionally associated with S. filix). Sticta lacera was not included in the present study due to the lack of authentic material (all specimens originally identified under that name and sequenced clustered with S. filix); S. filix was confirmed as a distinct species whereas S. latifrons s. lat. was shown to represent two unrelated species, S. latifrons s. str. and the reinstated S. menziesii Hook. f. & Taylor. The cyanomorphs of S. filix and S. latifrons are not conspecific with the types of the names D. dendriothamnodes and D. dendroides, respectively; the D. dendriothamnodes cyanomorph belongs to the Australian taxon Sticta stipitata C. Knight ex F. Wilson, which is not present in New Zealand, whereas the D. dendroides cyanomorph corresponds to a previously unrecognized species with unknown chloromorph, recombined here as Sticta dendroides (Nyl.) Moncada, Lücking & de Lange. Thus, instead of three species (S. filix, S. lacera, S. latifrons) with their corresponding cyanomorphs, five species are now distinguished in this guild in New Zealand: S. dendroides (cyanomorph only), S. filix (chloro- and cyanomorph), S. lacera (chloromorph only), S. latifrons (chloro- and cyanomorph) and S. menziesii (chloro- and cyanomorph). A key is presented for identification of the chloromorphs and the dendriscocauloid cyanomorphs of all species. Semi-quantitative analysis suggests that species in this guild are good indicators of intact forest ecosystems in New Zealand and that the two newly recognized species, S. dendroides and S. menziesii, appear to perform particularly well in this respect. The use of lichens as bioindicators of environmental health is not yet established inNew Zealand and so, based on our results, we make the case to develop this approach more thoroughly. [ABSTRACT FROM AUTHOR]