coastal arrow worm vs Common Fieldcap

Parasagitta setosa compared with Agrocybe pediades

Key Differences

coastal arrow worm is Not Evaluated while Common Fieldcap is Least Concern.

Taxonomic Classification

Rank	coastal arrow worm	Common Fieldcap
Kingdom	Animalia (Animals)	Fungi (Fungi)
Phylum	Chaetognatha (arrow worms)	Basidiomycota (Club Fungi)
Class	Sagittoidea (Sagittoidea)	Agaricomycetes (Mushrooms)
Order	Aphragmophora (Aphragmophora)	Agaricales (Gilled Mushrooms)
Family	Sagittidae	Strophariaceae
Genus	Parasagitta	Agrocybe
Species	Parasagitta setosa	Agrocybe pediades

Conservation Status

coastal arrow worm

NE — Not Evaluated

Common Fieldcap

LC — Least Concern

Physical Characteristics

Attribute	coastal arrow worm	Common Fieldcap
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

coastal arrow worm

Habitat

Native to Europe, inhabiting ecosystems characteristic of the region.

Range

Distributed across Denmark, Norway, and Russia.

Common Fieldcap

Habitat

Typically found in forest floors, decomposing wood, and soil ecosystems.

Range

Found across Europe (5 countries) and North America (United States).

coastal arrow worm

Parasagitta setosa, the coastal arrow worm, is a chaetognath in the family Sagittidae inhabiting the coastal and neritic waters of the northeastern Atlantic Ocean and adjacent North Sea and Baltic Sea, with confirmed records from Denmark, Norway, and Russia. Arrow worms are small, transparent, torpedo-shaped marine invertebrates typically 1–5 centimeters long, and despite their common name, are neither worms nor closely related to any familiar animal group; they form their own phylum, Chaetognatha, comprising around 120 species. Parasagitta setosa is a predatory planktonic species, using stiff bristle-like grasping spines flanking its mouth to seize copepods, small fish larvae, and other zooplankton that form the bulk of its diet. It occupies neritic plankton communities, often occurring in brackish coastal waters and estuaries where many arrow worm species cannot tolerate reduced salinity. The species serves as an important prey item for fish including herring and sprat and functions as a significant link in coastal marine food webs. Arrow worm phylogenetic position has been debated extensively; molecular evidence places them near the base of protostome animals. The species is Not Evaluated by the IUCN, as marine zooplankton populations are rarely assessed due to monitoring challenges.

Common Fieldcap

The Common Fieldcap (<em>Agrocybe pediades</em>) is a saprotrophic fungus belonging to the genus Agrocybe within the family Strophariaceae. It typically produces small, tan to pale brown cap-shaped fruiting bodies and is often found growing in clusters or scattered on lawns, grassy areas, forest floors, decomposing wood, and soil-rich ecosystems. The species typically inhabits forest floors, decomposing wood, and soil ecosystems, obtaining nutrients by breaking down dead organic matter. Its geographic range includes several European countries — Belgium, Denmark, Norway, Portugal, and Sweden — as well as the United States in North America. <em>Agrocybe pediades</em> is assessed as Least Concern on the IUCN Red List, reflecting its broad distribution and apparent stability. Biological traits of this species, including specific data on fruiting body size, lifespan, and ecological preferences, remain poorly documented in the scientific literature. Like other members of its genus, it typically fruits during warmer months and often appears after rainfall in nutrient-rich grassland and woodland habitats.