Coastal Silver-stiletto vs Common Ground-Pine

Acrosathe annulata compared with Dendrolycopodium obscurum

Key Differences

Coastal Silver-stiletto is Least Concern while Common Ground-Pine is Not Evaluated.

Taxonomic Classification

Rank	Coastal Silver-stiletto	Common Ground-Pine
Kingdom	Animalia (Animals)	Plantae (Plants)
Phylum	Arthropoda (Arthropods)	Tracheophyta
Class	Insecta (Insects)	Lycopodiopsida (Lycopodiopsida)
Order	Diptera (Diptera)	Lycopodiales (Lycopodiales)
Family	Therevidae	Lycopodiaceae
Genus	Acrosathe	Dendrolycopodium
Species	Acrosathe annulata	Dendrolycopodium obscurum

Conservation Status

Coastal Silver-stiletto

LC — Least Concern

Common Ground-Pine

NE — Not Evaluated

Physical Characteristics

Attribute	Coastal Silver-stiletto	Common Ground-Pine
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Coastal Silver-stiletto

Habitat

Typically found in virtually all terrestrial and freshwater habitats.

Range

Distributed across Belgium, Denmark, Norway, and Sweden.

Common Ground-Pine

Habitat

Native to North America, inhabiting ecosystems characteristic of the region.

Range

Distributed across Canada and United States.

Coastal Silver-stiletto

Coastal silver stiletto (Acrosathe annulata) is a slender robber fly in the family Therevidae, native to northwestern Europe, including the United Kingdom, France, the Netherlands, Belgium, and Scandinavia. Adults are found on coastal sand dunes and sandy heathland, where they perch on bare sand to ambush small flying insects. Stiletto flies in the family Therevidae are characterised by a slender body, long pointed abdomen, and predatory habits; adults prey on a variety of small dipterans and other flying insects during warm, sunny periods. Larvae develop in sandy soil, where they are also predatory, feeding on other invertebrate larvae. Acrosathe annulata is a habitat specialist restricted to open, sandy coastal habitats with sparse vegetation—environments that have declined substantially across northwestern Europe due to dune stabilisation, recreational disturbance, and the cessation of traditional dune management. The IUCN lists it as Least Concern, though regional conservation bodies in the United Kingdom have flagged population declines. It is considered an indicator of high-quality coastal sand dune habitats and is monitored through national invertebrate surveys.

Common Ground-Pine

The common ground pine, <em>Dendrolycopodium obscurum</em>, is a vascular plant belonging to the family Lycopodiaceae, a lineage of ancient clubmosses. This species is typically found across North America, with its known range encompassing Canada and the United States. As a lycophyte, <em>Dendrolycopodium obscurum</em> represents a deeply divergent lineage among land plants, distinct from mosses and ferns. The species typically grows in moist forested habitats, particularly in coniferous and mixed woodlands where humidity and leaf litter provide suitable conditions for its growth. Its upright, tree-like sporophylls give it the common name ground pine. No dietary information has been provided for this species. Biological traits of this species remain poorly documented in the scientific literature.