Debunking Korunomyces

Korunomyces is a genus including fungi that produce stipitate, profusely branched, multicellular asexual reproductive structures (propagules) on leaves and in culture. Three species have been described in the genus: Korunomyces terminaliae – the type species, K. prostratus and K. zapatensis. No molecular studies have ever been conducted to elucidate the phylogenetic placement of Korunomyces. Recently, DNA sequences were obtained from pure cultures of K. prostratus and K. terminaliae, enabling an elucidation of their taxonomic placement. Isolates of K. prostratus obtained from diseased tissues of Miconia calvescens were observed for the first time to form pycnidial conidiomata in culture. A multi-gene phylogeny, including the large subunit of the nrDNA (nc LSU rDNA), internal transcribed spacer (ITS) region, polymerase II second largest subunit (RPB2) and translation elongation factor 1-α (TEF1), placed K. prostratus and K. terminaliae within Coniella (Schizoparmaceae). As Korunomyces is younger than Coniella, it is reduced to synonymy, and a new name and a new combination are proposed for these two species, namely: Coniella ferreirense nom. nov. and Coniella prostrata comb. nov. An emended description of Coniella to include the occasional formation of distinct and elaborate asexual propagules is also provided.

Comparing Interpretation of High-Resolution Aerial Imagery by Humans and Artificial Intelligence to Detect an Invasive Tree Species

Timely, accurate maps of invasive plant species are critical for making appropriate management decisions to eliminate emerging target populations or contain infestations. High-resolution aerial imagery is routinely used to map, monitor, and detect invasive plant populations. While conventional image interpretation involving human analysts is straightforward, it can require high demands for time and resources to produce useful intelligence. We compared the performance of human analysts with a custom Retinanet-based deep convolutional neural network (DNN) for detecting individual miconia (Miconia calvescens DC) plants, using high-resolution unmanned aerial system (UAS) imagery collected over lowland tropical forests in Hawai’i. Human analysts (n = 38) examined imagery at three linear scrolling speeds (100, 200 and 300 px/s), achieving miconia detection recalls of 74 ± 3%, 60 ± 3%, and 50 ± 3%, respectively. The DNN achieved 83 ± 3% recall and completed the image analysis in 1% of the time of the fastest scrolling speed tested. Human analysts could discriminate large miconia leaf clusters better than isolated individual leaves, while the DNN detection efficacy was independent of leaf cluster size. Optically, the contrast in the red and green color channels and all three (i.e., red, green, and blue) signal to clutter ratios (SCR) were significant factors for human detection, while only the red channel contrast, and the red and green SCRs were significant factors for the DNN. A linear cost analysis estimated the operational use of a DNN to be more cost effective than human photo interpretation when the cumulative search area exceeds a minimum area. For invasive species like miconia, which can stochastically spread propagules across thousands of ha, the DNN provides a more efficient option for detecting incipient, immature miconia across large expanses of forested canopy. Increasing operational capacity for large-scale surveillance with a DNN-based image analysis workflow can provide more rapid comprehension of invasive plant abundance and distribution in forested watersheds and may become strategically vital to containing these invasions.

Structure of ant-diaspore networks and their functional outcomes in a Brazilian Atlantic Forest

Ants are able to interact with fruits and seeds that are not adapted for ant seed dispersal. In Brazil, several studies show interactions of ants with non-myrmecochorous diaspores; however, few of them have studied the structure of ant-fruit networks. The use of the network approach allows visualising multiple interactions between partners and how they are shaped by the community context. Our study aims to investigate ant-fruit networks as well as quantitative and qualitative dispersal components in a fragment of the Brazilian Atlantic Forest. We investigated the structure of interaction networks, diaspore removal rates, diaspore destination and dispersal distance over two years of observation. We constructed three interaction networks: dry season, rainy season and total, with the latter comprising the two formers. The diaspore removal rate, dispersal distance and diaspore destination experiments were performed for the plant species Miconia calvescens, Miconia prasina, Psychotria leiocarpa and Inga edulis. We recorded a large number of interactions, with diaspore cleaning being more frequent than removal. Ant-diaspore networks were nested, non-modular and little specialized. M. calvescens, M. prasina and I. edulis showed higher diaspore removal rates. Diaspore removal distances were the same among M. calvescens, M. prasina and I. edulis. In M. calvescens and I. edulis, the main diaspore destination was the ant’s nest. Our study shows that diaspore cleaning is the most common behavior in ant-diaspore interactions and there are no differences in the organization of interaction networks over the seasons. These results have implications for the future structure of plant communities, considering that a small part of the diaspores is removed, and that most of them are cleaned, favouring germination at the deposition site.

Miconia calvescens (miconia).

A datasheet on Miconia calvescens covering, as an economically important tree, its taxonomy, importance, silviculture, distribution, biology and ecology, uses, products and pests.

Description, Biology, and Impact of the Fruit-Feeding Moth, Mompha luteofascia sp. n. (Lepidoptera: Momphidae), on Miconia calvescens (Melastomataceae) in Costa Rica

Fruits of Miconia calvescens DC. (Melastomataceae) were dissected to study insect frugivory in this plant in its native habitat in Costa Rica. Larvae of an unknown Mompha species (Lepidoptera: Momphidae), Anthonomus monostigma Champion (Coleoptera: Curculionidae), and unidentified Diptera and Hymenoptera were found in M. calvescens fruits. The Mompha species, described here as new as Mompha luteofascia Koster & Badenes-Pérez, was the most abundant insect frugivore in M. calvescens, infesting up to 38.1% of the fruits sampled. Feeding damage by M. luteofascia was positively correlated with fruit maturity, and resulted in significantly reduced numbers of seeds and rates of seed germination. Miconia calvescens fruits with medium damage (50–75% of the pulp missing) and high damage (75–100% of the pulp missing) had an average of 96 and 99 seeds, respectively, whereas undamaged fruits contained an average of 127 seeds per fruit. In fruits with medium and high fruit damage, only 1.9 and 0.1% of the seeds germinated, respectively, whereas 34.8% of the seeds germinated in undamaged fruits. Mompha luteofascia developed through three instars, as determined from measurement of head capsules. Larvae usually fed as one individual per each fruit attacked, exiting fruit to pupate in foliage or litter. Parasitism of M. luteofascia larvae was substantial, averaging 64 and 38% at the two study sites. Although host specificity of M. luteofascia has not been evaluated, the significant reductions in seed numbers and seed germination caused by its larvae indicate that this species deserves further assessment as a potential biological control agent of M. calvescens.

Interpreting Life-History Traits of Miconia (Miconia calvescens) through Management over Space and Time in the East Maui Watershed, Hawaii (USA)

Miconia (Miconia calvescens DC) was introduced to the East Maui Watershed (EMW) a half-century ago with more than 25 yr of management recorded. Using a historical spatiotemporal data set, we constructed a leptokurtic dispersal kernel with 99% of progeny confined to within 549 m of the nearest maternal source and the remaining 1% dispersed out to 1,636 m. Seedbank persistence, based on postdated recruitment, displayed an exponential decay projecting extinction beyond 20 yr. These parameters are highly congruent to independent interpretations of M. calvescens in Australia and Tahiti. In a simulated stage matrix model, we projected management efforts to locally eradicate a small incipient propagule bank wherein optimal management was achieved with an annual harvest rate that eliminated all juvenile recruits before reaching maturity, until extinction. Based on current pricing for helicopter herbicide ballistic technology (HBT) operations, the optimal, variable cost to locally eradicate this incipient propagule bank was estimated to be less than US$42,000, with ~90% of the effort searching for the most distant 1% of the progeny expended within the first 9 yr after the mature discovery. This variable cost was sensitive to seedbank size, recruitment rate, and dispersal range, but was most sensitive to harvest rates between suboptimal and excess. In a scenario prioritizing the upper region of EMW, we retroactively analyzed past HBT efforts eliminating satellite M. calvescens and determined that 27% of the total effort resulted in 87% of the total protection to this priority asset, with every US$1 invested potentially avoiding US$184 in future costs. Management outside the priority area was less economical, with returns in protection diminishing with distance from the priority upper region. Miconia calvescens is currently not eradicable in the EMW, and full containment of the invasion would require a substantial increase in stable, long-term funding. With limited resources, local eradication of satellite M. calvescens could be the most cost-effective alternative to protecting uninvaded areas prioritized for critical ecosystem functions.