Lucilia silvarum

(Meigen, 1826)

common toad fly, Marsh Greenbottle Fly

Lucilia silvarum is a in the , first described by Johann Wilhelm Meigen in 1826. are 4.5–10 mm with metallic green coloration and , making them difficult to distinguish from related green bottle . The has a Holarctic distribution across North America and Europe. Recent research has clarified its ecological role: it is primarily on carrion and was identified as a primary colonizer of domestic cats in experimental studies, contradicting earlier assumptions that it was strictly associated with amphibian .

Lucilia silvarum by (c) Don Loarie, some rights reserved (CC BY), uploaded by Don Loarie. Used under a CC-BY license.

Lucilia silvarum by no rights reserved, uploaded by Uffe Harboe Nygaard. Used under a CC0 license.

Marsh Greenbottle Fly (Lucilia silvarum) - Guelph, Ontario 2020-07-26 by Ryan Hodnett. Used under a CC BY-SA 4.0 license.

Pronunciation

How to pronounce Lucilia silvarum: //luːˈsɪliə ˈsɪlvərəm//

These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.

Identification

Difficult to distinguish from other green bottle (Lucilia spp.) based on alone; accurate identification requires examination of specific morphological characters or molecular analysis; distinguished from L. sericata and L. cuprina by subtle differences in thoracic and ; historically confused with L. bufonivora, which is now recognized as the primary agent of anuran in North America rather than L. silvarum

Images

Habitat

Open grassy fields; areas with decomposing animal matter; warmweather environments with temperatures between 24–29°C (75–85°F); associated with carrion, , and filth concentrations; saline conditions in California (incidental finding)

Distribution

Holarctic: widespread throughout North America and Europe; documented from British Columbia, Canada to southern Florida, USA; recorded in China, Denmark, Finland, southern Norway, Russia, and Canada; present in Vermont, USA; Sweden; Norway

Seasonality

Warmweather ; active during periods with temperatures between 24–29°C; presumably active spring through fall in temperate regions, with exact timing varying by latitude

Diet

Carrion; nectar and sweet liquids (); decomposing animal tissue; has been observed on domestic cat carcasses, rat carcasses, duck carcasses, and mice carcasses

Life Cycle

hatch in approximately one day; three larval : first instar at approximately 2 days, second instar at approximately 2.5 days, third instar at 4–5 days; prepupal wandering stage occurs 8–12 days after , with reaching up to 12 mm; occurs after approximately 18–24 days depending on atmospheric conditions; development rates vary with temperature, humidity, and other environmental factors

Behavior

locate carrion by olfaction, attracted to sulfurbased and ammonium-rich volatile compounds; uses visual stimuli to supplement olfactory cues when locating decomposing remains; arrives at remains almost immediately after exposure; females oviposit on carrion; exhibit post-feeding (wandering) before

Ecological Role

Primary colonizer of decomposing remains; contributes to decomposition and ; forensically relevant for estimating time of and postmortem interval; part of initial wave of arriving at fresh remains; may prefer smaller carcasses or resources with low competition

Human Relevance

: important for estimating time of death in human and animal cases; one of the first to colonize corpses in the United States and Canada; empty indicates postmortem interval of at least 20 days; relevant for animal cruelty investigations; NOT used in (medical debridement uses L. sericata, not L. silvarum)

Similar Taxa

Lucilia sericataSimilar metallic green appearance and size; both common green bottle ; L. sericata is the used in medicinal and is more extensively studied forensically
Lucilia cuprinaSimilar metallic green coloration; Australian sheep ; worldwide by human commerce
Lucilia bufonivoraHistorically confused with L. silvarum; now recognized as the true agent of fatal anuran in North America, not L. silvarum; subtle morphological differences require expert examination to distinguish
Phormia reginaBlack with different coloration but similar forensic importance; differs in being black or deep metallic black rather than green; seasonal activity pattern differs (spring and fall vs. warm weather)

Misconceptions

Previously believed to cause fatal in anurans (frogs and toads) in North America; recent molecular and morphological evidence (2019–2020) demonstrates that L. bufonivora, not L. silvarum, is responsible for anuran myiasis in North America; L. silvarum appears to be strictly in both Nearctic and Palearctic regions