Monalocoris filicis
In 3 days ~10% in a week ~20%
Monalocoris filicis, commonly known as the bracken bug, is a true bug in the family Miridae. The species is found in Europe from Ireland in the West and including the northern edge of the Mediterranean and the East across the Palearctic to Central Asia, Korea and Japan. In Central Europe, it is widespread and generally common. In the Alps, it occurs up to the edge of the forest. Habitats are deciduous and coniferous forests and moist, open habitats such as bogs or the shores of streams.
Adults are 2.0-3.1 mm long and are a golden brown color, and have a pale-orange head and are therefore easily identifiable. They are similar to Bryocoris pteridis from which they can be distinguished by the first segment of the antenna, which is shorter than the head is wide. The adult animals are always fully winged (macropterous).
Monalocoris filicis feeds on Dryopteris filix-mas and Pteridium aquilinum occasionally alongside Monalocoris parvulus. They suck especially immature spore plants in late summer. The males are strong fliers and swarm during the mating season, when they are found also on other plants. The females lay green eggs from May until early June on the host plants, where they are indistinguishable from the similarly colored spores. Nymphs are found primarily in June and July, adult bugs from the end of June to the mating season. In the September/early October, the imagines leave the host plants to overwinter, hibernating as an imago in the dry remains of their host plants on the ground, in the leaf litter or branches of conifers (usually Picea abies). Wikipedia →
| # | Park | Country | Daily sighting probability |
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More parks will be added in future updates.
Rare
Under 5% of wildlife watchers report a Bracken Bug sighting in Tokyo on a given day, based on 6 verified sightings from GBIF citizen-science data. It is the 872nd most-seen of the 1013 insects we can rate there. Over three days the chance rises to about 10%, and over a week to about 20%, if each day is a fresh chance.
Any time of year
In every month with enough records, under 5% of wildlife watchers report a Bracken Bug in Tokyo on a given day, so our monthly data shows no clear season.
Among the best
Of the 2 cities where we can rate Bracken Bug sightings, Tokyo ranks 2nd at under 5%, level with the leaders once rounded. The best odds are in Helsinki (Finland, under 5%).
GBIF citizen-science records
It is estimated from how often the Bracken Bug is recorded against all the insects logged in Tokyo (6 verified sightings), calibrated against known sighting rates. Figures are rounded to the nearest 10% because citizen-science data supports honest approximations, not decimals, and months with records from fewer than five people show "—". How it works.
