Phormia Terranova
   HOME

TheInfoList



OR:

''Protophormia terraenovae'' is commonly called northern blowfly, blue-bottle fly or blue-assed fly (blue-arsed fly in
British English British English is the set of Variety (linguistics), varieties of the English language native to the United Kingdom, especially Great Britain. More narrowly, it can refer specifically to the English language in England, or, more broadly, to ...
). It is distinguished by its deep blue coloration and large size and is an important species throughout the Northern Hemisphere. This fly is notable for its economic effect as a
myiasis Myiasis ( ), also known as flystrike or fly strike, is the parasitic infestation of the body of a live animal by fly larvae (maggots) that grow inside the host while feeding on its Biological tissue, tissue. Although flies are most commonly attr ...
pest of livestock and its
antibiotic An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting pathogenic bacteria, bacterial infections, and antibiotic medications are widely used in the therapy ...
benefits in
maggot therapy Maggot debridement therapy (also known as MDT, larval therapy, or simply maggot therapy) is a type of biotherapy involving the introduction of live, disinfected maggots (fly larvae) into non-healing skin and soft-tissue wounds of a human or othe ...
. Also of interest is ''P. terraenovae''’s importance in
forensic Forensic science combines principles of law and science to investigate criminal activity. Through crime scene investigations and laboratory analysis, forensic scientists are able to link suspects to evidence. An example is determining the time and ...
investigations: because of their temperature-dependent development and their prominent presence on corpses, the larvae of this species are useful in minimum
post-mortem interval The post-mortem interval (PMI) is the time that has elapsed since an individual's death. When the time of death is not known, the interval may be estimated, and so an approximate time of death established. Postmortem interval estimations can ra ...
(mPMI) determination.


Taxonomy

''Protophormia terraenovae'', of the
family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...
Calliphoridae The Calliphoridae (commonly known as blowflies, blow flies, blow-flies, carrion flies, bluebottles, or greenbottles) are a family of insects in the order Diptera, with almost 1,900 known species. The maggot larvae, often used as fishing bait, ...
, was named and first described by French entomologist
André Jean Baptiste Robineau-Desvoidy André Jean Baptiste Robineau-Desvoidy (1 January 1799 in Saint-Sauveur-en-Puisaye – 25 June 1857 in Paris) was a French physician and entomologist specialising in the study of Diptera (flies), and to some extent of the Coleoptera (beetles). Fl ...
in his 1830 “Essai sur les myodaires.” Its
genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...
is shared by one other fly, ''Protophormia atriceps''. Both flies are a dark, undusted, metallic blue-green-black. ''P. terraenovae'' is differentiated from ''P. atriceps'' by its flat face, plumose arista, and by up to 2 additional pairs of
setae In biology, setae (; seta ; ) are any of a number of different bristle- or hair-like structures on living organisms. Animal setae Protostomes Depending partly on their form and function, protostome setae may be called macrotrichia, chaetae ...
along the margin of the scutellum. ''P. terraenovae''’s specific epithet is translated from the
Latin Latin ( or ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken by the Latins (Italic tribe), Latins in Latium (now known as Lazio), the lower Tiber area aroun ...
as “of the New World.” The oldest-known specimens of ''P. terraenovae'' pupae were identified in 1973 within the fossilized skull of a
steppe wisent The steppe bison (''Bison'' ''priscus'', also less commonly known as the steppe wisent and the primeval bison) is an extinct species of bison which lived from the Middle Pleistocene to the Holocene. During the Late Pleistocene, it was widely dist ...
. The bison skull, estimated to date from the late
Eemian The Last Interglacial, also known as the Eemian, was the interglacial period which began about 130,000 years ago at the end of the Penultimate Glacial Period and ended about 115,000 years ago at the beginning of the Last Glacial Period. It cor ...
period, was excavated from the site of a new
sluice A sluice ( ) is a water channel containing a sluice gate, a type of lock to manage the water flow and water level. There are various types of sluice gates, including flap sluice gates and fan gates. Different depths are calculated when design s ...
for the Brussels-Rupel Canal in Zemst, Belgium. The specimens, although approximately 75,000 years old, are identical in form to the pupae of the modern species.


Morphology


Adult

The adult ''Protophormia terraenovae'', one of the larger
species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...
of calliphorids, measures between 7 and 12 mm in length.Byrd, Jason, and James Castner (2001). ''Forensic Entomology: The Utility of Arthropods in Legal Investigations'', CRC Press, New York. . It is characterized by a black to brown anterior thoracic spiracle,Wall, Richard, and David Shearer. ''Veterinary Entomology: Arthropod ectoparasites of veterinary importance''. London: Chapman & Hall, 1997. a black basicosta, brown wing veins, and dark
calypters A calypter is either of two posterior lobes of the posterior margin of the forewing of flies between the extreme posterior wing base and the alula, which covers the halteres. The lower calypter is the proximal calypter (synonyms: squama (of som ...
. Upper calypters sprout black setae. While the thorax and abdomen of ''P. terraenovae'' can range in color from dark purple to dark green, the head and legs of this fly are black. Postocular setae are short but prominent; the
palpi Pedipalps (commonly shortened to palps or palpi) are the secondary pair of forward appendages among chelicerates – a group of arthropods including spiders, scorpions, horseshoe crabs, and sea spiders. The pedipalps are lateral to the chelicera ...
are yellow or dusky brown.Rognes, Knut. "Blowflies (Diptera, Calliphoridae) of Fennoscandia and Denmark." ''Fauna Entomologica Scandinavia'' 24. Leiden: E.J. Brill/Scandinavian Science Press Ltd. 1991. Sexes of the species are easily distinguished by the width of the space between the eyes, the
frons Insect morphology is the study and description of the physical form of insects. The terminology used to describe insects is similar to that used for other arthropods due to their shared evolutionary history. Three physical features separate insec ...
: that of the female is .386 times the width of the head, while the frons of the male is only .140 times the head width. Chaetotaxy, the study of setae arrangement, is also useful for determination of sex—for example, the male lacks the fronto-orbital, lateroclinate setae found in the female. These setae are located just at the edge of the frons, near the upper portion of the complex eyes.


Larvae

''Protophormia terraenovae''
larva A larva (; : larvae ) is a distinct juvenile form many animals undergo before metamorphosis into their next life stage. Animals with indirect development such as insects, some arachnids, amphibians, or cnidarians typically have a larval phase ...
e are tiny and white, with 12 segments. Length varies by larval age, with the first
instar An instar (, from the Latin '' īnstar'' 'form, likeness') is a developmental stage of arthropods, such as insects, which occurs between each moult (''ecdysis'') until sexual maturity is reached. Arthropods must shed the exoskeleton in order to ...
growing up to 2.63 mm and the third, by contrast, as long as 11.87 mm. In the third instar, the last segment is adorned with pointed
tubercles In anatomy, a tubercle (literally 'small tuber', Latin for 'lump') is any round nodule, small eminence, or warty outgrowth found on external or internal organs of a plant or an animal. In plants A tubercle is generally a wart-like projection, b ...
, and segment 10 exhibits dorsal spines along its posterior margin. The latter characteristic distinguishes ''P. terraenovae'', 3rd instar, from a similar calliphorid, ''
Phormia regina ''Phormia regina'', the black blow fly, belongs to the blow fly family Calliphoridae and was first described by Johann Wilhelm Meigen. The black blow fly's wings are specialized with a sharp bend. These flies also have well-developed calypters. ...
''.


Development

Being of the order
Diptera Flies are insects of the order Diptera, the name being derived from the Greek δι- ''di-'' "two", and πτερόν ''pteron'' "wing". Insects of this order use only a single pair of wings to fly, the hindwings having evolved into advance ...
, ''Protophormia terraenovae'' is
holometabolous Holometabolism, also called complete metamorphosis, is a form of insect development which includes four life stages: egg, larva, pupa, and imago (or adult). Holometabolism is a synapomorphic trait of all insects in the clade Holometabola. Immatur ...
in its development, meaning it experiences dramatic changes from immature to adult. ''Protophormia terraenovae'' undergoes three instars, a pupal stage, and finally an adult stage. First instar larvae obtain a liquid diet from orifices or wounds of a body. The instars that follow digest the body itself. Among the first to colonize, Calliphoridae species are found on the body almost immediately. As eggs hatch into the first larval stage, ''P. terraenovae'' begins feeding and increases in size, limited by its chitinous outer
cuticle A cuticle (), or cuticula, is any of a variety of tough but flexible, non-mineral outer coverings of an organism, or parts of an organism, that provide protection. Various types of "cuticle" are non- homologous, differing in their origin, structu ...
. As ''P. terraenovae'' larvae molt into the second instar, feeding intensifies: with larger and more developed mouthparts, second instars are able to break down tougher body tissues. Warren, Jodie-Ann. "The Development of Protophormia terraenovae at Constant and Fluctuating Temperatures

Simon Fraser University, 1999."
The third instar is unique, consisting of several substages. First, the larvae feed until they reach their maximum size. Next, larvae clear their crops. In this prepupal stage, also called the wandering stage, the
maggots A maggot is the larva of a fly (order Diptera); it is applied in particular to the larvae of Brachycera flies, such as houseflies, cheese flies, hoverflies, and blowflies, rather than larvae of the Nematocera, such as mosquitoes and cran ...
seek a dry, safe area for pupation. During the pupal stage, the outer cuticle hardens and tans into a dark brown color, gradually darkening with age. Finally, metamorphosis into the adult is completed with the shedding of the pupal casing and the emergence of the fly. The time of development between instars to pupae to adult differs depending on temperatures. The mean duration of development, at constant pressure and 25 °C, between oviposition and hatching is 1.83 days. From first to second instar, approximately 2.92 days pass. About 6.17 days pass between the second and third instar, and 8.0 days between the third instar and the post-feeding stage. The wandering maggot takes around 9.67 days to reach the pupal stage. Lastly, emergence of this blowfly occurs about 15.83 days after pupation. In fluctuating conditions such as those around crime scenes, there is a tendency for development to slow down. Under-approximation of age is therefore a common mistake. The development of ''P. terraenovae'' is inversely related to temperature. Studies at (15, 20, 25, 30, 35)°C were performed, and the minimal duration of development from
oviposition The ovipositor is a tube-like organ used by some animals, especially insects, for the laying of eggs. In insects, an ovipositor consists of a maximum of three pairs of appendages. The details and morphology of the ovipositor vary, but typica ...
to adult ranges from 9.19 ± .3 days at 35 °C, to 37.78 ± 2.96 days at 15 °C. The minimum development threshold for total immature development is 8.95 °C. The overall thermal constant (K) for ''P. terraenovae'' is 240.2 ± 9.3 day-degrees above threshold. The inverse relationship and regression of development from oviposition to pupation resulted in a 9.8 °C threshold for the species.Grassberger, Martin, and Christian Reiter. "Effect of Temperature on Development of the Forensically Important Holarctic Blow Fly ''Protophormia terraenovae'' (Robineau-Desvoidy) (Diptera: Calliphoridae)." ''Forensic Science International'' 128 (2002): 177-182. Pupation occurs on or within .5 meters of the decaying body. The duration of the pupal stage is relatively long compared to the rest of development, inactively occupying 43% of ''P. terraenovae''’s total cycle. The third instar larva spends 13% of its cycle in feeding stage and 22% in post-feeding stages.


Geographic distribution

''Protophormia terraenovae'' has a
Holarctic The Holarctic realm is a biogeographic realm that comprises the majority of habitats found throughout the continents in the Northern Hemisphere. It corresponds to the floristic Boreal Kingdom. It includes both the Nearctic zoogeographical reg ...
distribution, meaning the species is found throughout the northern hemisphere. The fly is common in cool regions and, being "the most cold tolerant of all calliphorid species," can withstand extreme temperatures. ''P. terraenovae'' can be found as close as 550 miles from the North Pole and is abundantly found in the Arctic. In
North America North America is a continent in the Northern Hemisphere, Northern and Western Hemisphere, Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South Ameri ...
, ''P. terraenovae'' can be found from
Mexico Mexico, officially the United Mexican States, is a country in North America. It is the northernmost country in Latin America, and borders the United States to the north, and Guatemala and Belize to the southeast; while having maritime boundar ...
to
Canada Canada is a country in North America. Its Provinces and territories of Canada, ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, making it the world's List of coun ...
. Appearance of this species is rare and mostly confined to the winter months in warm regions such as
Texas Texas ( , ; or ) is the most populous U.S. state, state in the South Central United States, South Central region of the United States. It borders Louisiana to the east, Arkansas to the northeast, Oklahoma to the north, New Mexico to the we ...
and
Florida Florida ( ; ) is a U.S. state, state in the Southeastern United States, Southeastern region of the United States. It borders the Gulf of Mexico to the west, Alabama to the northwest, Georgia (U.S. state), Georgia to the north, the Atlantic ...
. ''P. terraenovae'' is a spring or summer species in high latitudes and elevations.


Importance


Medical

Maggot debridement therapy (MDT) is commonly used for the cleansing and disinfecting of chronic wounds containing
necrotic Necrosis () is a form of cell injury which results in the premature death of cells in living tissue by autolysis. The term "necrosis" came about in the mid-19th century and is commonly attributed to German pathologist Rudolf Virchow, who is ...
flesh. Various studies have shown that MDT is effective in treating wounds that have failed to heal. Effective MDT species consume necrotic tissue while cleansing the wound.Kočišová, A., J. Pistl, R. Link, E. Čonková, and M. Goldová. "Maggot Debridement Therapy in the Treatment of Footrot and Foot Scald in Sheep." ''Acta Vet. Brno'' 75 (2006): 277-81. ''Protophormia terraenovae'' is among the few blowfly species that fit these criteria. The larvae of most blowflies are
necrophagous Necrophages are organisms that obtain nutrients by consuming decomposing dead animal biomass, such as the muscle and soft tissue of carrion, carcasses and cadaver, corpses (also known as carrion). The term derives from Greek , meaning 'dead', and ...
, meaning they develop in the bodies of dead vertebrates where they consume necrotic tissues. Because the majority of other blowfly larvae consume both necrotic and healthy tissues, ''P. terraenovae'' is an important species. ''P. terraenovae'' is also known to produce antibiotics during feeding: the secretions of ''P. terraenovae'' larvae are effective in fighting infections involving ''
Streptococcus pyogenes ''Streptococcus pyogenes'' is a species of Gram-positive, aerotolerant bacteria in the genus '' Streptococcus''. These bacteria are extracellular, and made up of non-motile and non-sporing cocci (round cells) that tend to link in chains. They ...
'' and ''
Streptococcus pneumoniae ''Streptococcus pneumoniae'', or pneumococcus, is a Gram-positive, spherical bacteria, hemolysis (microbiology), alpha-hemolytic member of the genus ''Streptococcus''. ''S. pneumoniae'' cells are usually found in pairs (diplococci) and do not f ...
''. The main concern with the use of MDT is
sepsis Sepsis is a potentially life-threatening condition that arises when the body's response to infection causes injury to its own tissues and organs. This initial stage of sepsis is followed by suppression of the immune system. Common signs and s ...
. P. terraenovae is blamed for five reported bloodstream
infections An infection is the invasion of tissue (biology), tissues by pathogens, their multiplication, and the reaction of host (biology), host tissues to the infectious agent and the toxins they produce. An infectious disease, also known as a transmis ...
. To prevent infection, ''P. terraenovae'' maggots must be raised ''in vitro'' under sterile conditions. Provided these precautions are taken, the use of ''P. terraenovae'' on chronic wounds appears to remain safe and efficient in wound treatment.


Economic

As a species of the blowfly
family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...
Calliphoridae, ''Protophormia terraenovae'' causes economically important myiasis in livestock and, occasionally, in humans. It also affects other populations of
Diptera Flies are insects of the order Diptera, the name being derived from the Greek δι- ''di-'' "two", and πτερόν ''pteron'' "wing". Insects of this order use only a single pair of wings to fly, the hindwings having evolved into advance ...
due to the predacious nature of its larvae when competing for
necrotic Necrosis () is a form of cell injury which results in the premature death of cells in living tissue by autolysis. The term "necrosis" came about in the mid-19th century and is commonly attributed to German pathologist Rudolf Virchow, who is ...
tissue. ''P. terraenovae'' larvae have also been known to behave cannibalistically.Green, A. A. "The Control of Blowflies Infesting Slaughter-Houses I. Field observations of the habits of blowflies." ''Annals of Applied Biology'' 38 (1951): 475-494. Myiasis due to ''Protophormia terraenovae'' has been reported in both wild and domestic animals, but it most commonly affects livestock. Species usually oviposit on
carrion Carrion (), also known as a carcass, is the decaying flesh of dead animals. Overview Carrion is an important food source for large carnivores and omnivores in most ecosystems. Examples of carrion-eaters (or scavengers) include crows, vultures ...
, but are capable of oviposition in the wounds of livestock and wild animals. Thus, ''P. terraenovae'' acts as a secondary invader in causing myiasis. Commonly referred to as ‘wound strike’, lesions are foul smelling
ulcers An ulcer is a discontinuity or break in a bodily membrane that impedes normal function of the affected organ. According to Robbins's pathology, "ulcer is the breach of the continuity of skin, epithelium or mucous membrane caused by sloughing ...
that are filled with larvae. Animals infected with myiasis may die from toxemia and
sepsis Sepsis is a potentially life-threatening condition that arises when the body's response to infection causes injury to its own tissues and organs. This initial stage of sepsis is followed by suppression of the immune system. Common signs and s ...
. In particular, ''Protophormia terraenovae'' causes facultative,
cutaneous Skin is the layer of usually soft, flexible outer tissue covering the body of a vertebrate animal, with three main functions: protection, regulation, and sensation. Other animal coverings, such as the arthropod exoskeleton, have different d ...
myiasis of cattle, sheep and reindeer in the northern Holarctic region. Larvae feeding on the skin of sheep causes distress to the animal and loss of wool.Pedigo, Larry P. ''Economic Thresholds for Integrated Pest Management''. Ed. Leon G. Higley. Lincoln: University of Nebraska P, 1996. This skin damage occurs to a lesser extent in horses, goats and pigs. Adults of this species are capable of causing myiasis but are found only in the
Palaearctic The Palearctic or Palaearctic is a biogeographic realm of the Earth, the largest of eight. Confined almost entirely to the Eastern Hemisphere, it stretches across Europe and Asia, north of the foothills of the Himalayas, and North Africa. Th ...
and
Nearctic The Nearctic realm is one of the eight biogeographic realms constituting the Earth's land surface. The Nearctic realm covers most of North America, including Greenland, Central Florida, and the highlands of Mexico. The parts of North America ...
regions. Also of economic significance are manifestations of the species in slaughter-houses and
poultry Poultry () are domesticated birds kept by humans for the purpose of harvesting animal products such as meat, Eggs as food, eggs or feathers. The practice of animal husbandry, raising poultry is known as poultry farming. These birds are most typ ...
houses. Populations of ''P. terraenovae'' are maintained by
refuse Waste are unwanted or unusable materials. Waste is any substance discarded after primary use, or is worthless, defective and of no use. A by-product, by contrast is a joint product of relatively minor economic value. A waste product may beco ...
and the carcasses of dead animals. Due to their predacious nature, large numbers of this species can populate in the presence of other Dipteran species. Blowfly bred at these locations cause considerable local nuisance and may spread disease to both humans and animals by contaminating meat and foodstuffs.


Forensic

Medicocriminal
entomology Entomology (from Ancient Greek ἔντομον (''éntomon''), meaning "insect", and -logy from λόγος (''lógos''), meaning "study") is the branch of zoology that focuses on insects. Those who study entomology are known as entomologists. In ...
is the branch of
forensic entomology Forensic entomology is a branch of applied entomology that uses insects and other arthropods as a basis for legal evidence. Insects may be found on cadavers or elsewhere around crime scenes in the interest of forensic science. Forensic entom ...
dealing with the use of
arthropod Arthropods ( ) are invertebrates in the phylum Arthropoda. They possess an arthropod exoskeleton, exoskeleton with a cuticle made of chitin, often Mineralization (biology), mineralised with calcium carbonate, a body with differentiated (Metam ...
evidence in criminal investigations. Because they make up the first wave of
fauna Fauna (: faunae or faunas) is all of the animal life present in a particular region or time. The corresponding terms for plants and fungi are ''flora'' and '' funga'', respectively. Flora, fauna, funga and other forms of life are collectively ...
to colonize a corpse, blowflies are among the most accurate forensic indicators of time elapsed since death, technically referred to as the ''post-mortem'' interval (PMI). This estimation is made by determining the developmental stages of the insects present on a body. ''Protophormia terraenovae'' is forensically important because of its extremely specific developmental time. Two methods are used to determine the PMI of a ''P. terraenovae''-infested body. One approach utilizes information about the developmental stages of larvae located on or within the body, and the second utilizes facts about the larval stage as it emerges from the body to pupate. The first, second, and third instar larvae present on a body are considered to be feeding stages. The first and second
molting In biology, moulting (British English), or molting (American English), also known as sloughing, shedding, or in many invertebrates, ecdysis, is a process by which an animal casts off parts of its body to serve some beneficial purpose, either at ...
are characterized by rapid increases in size and generally occur within a certain range of larval length. Because the development of these flies is dependent on temperature, entomologists can use past weather data to estimate the ages of larvae and even pupae discovered on a corpse. When post-feeding larvae venture away from the body to pupate, as is common for most blowflies, displacement behavior becomes the determining factor of age.Charabidze, Damien, Benoit Bourel, Helene LeBlanc, Valery Hedouin, and Didier Gosset. "Effect of Body Length and Temperature on the Crawling Speed of ''Protophormia terraenovae'' Larvae (Robineau-Desvoidy) (Diptera Calliphoridae)." ''Journal of Insect Physiology'' 54 (2008): 529-533. When a body is discovered, if the larvae are leaving, it is possible to measure the distance they have traveled and, with knowledge of the species' crawling speed, to calculate when they left the body. Crawling speed is affected by terrain, temperature, and maggot length. These considerations allow forensic entomologists to make precise age estimations. Another noteworthy forensic consideration is the use of blowfly species, in this case ''Protophormia terraenovae'', in
entomotoxicology In forensic entomology, entomotoxicology is the analysis of toxins in arthropods (mainly flies and beetles) that feed on carrion. Using arthropods in a corpse or at a crime scene, investigators can determine whether toxins were present in a body at ...
. Evidence of drug use can be found in blowflies feeding upon cadavers with ''post-mortem'' drugs in their systems. Studies have shown that unlike other species of necrophagous Diptera, blowfly species can indicate the presence of
morphine Morphine, formerly also called morphia, is an opiate that is found naturally in opium, a dark brown resin produced by drying the latex of opium poppies (''Papaver somniferum''). It is mainly used as an analgesic (pain medication). There are ...
in the
cuticle A cuticle (), or cuticula, is any of a variety of tough but flexible, non-mineral outer coverings of an organism, or parts of an organism, that provide protection. Various types of "cuticle" are non- homologous, differing in their origin, structu ...
during larval growth, and, definitively, in pupa casings. Because puparial cases decay at an extremely slow rate and can be recovered years after the death of an individual, they can become very important to the examination of a corpse.


The "Pig Farm Case"

In 2007, entomological evidence was used in the infamous “Pig Farm Case”. An eighteen-month-long search of several acres of farmland and property in
British Columbia British Columbia is the westernmost Provinces and territories of Canada, province of Canada. Situated in the Pacific Northwest between the Pacific Ocean and the Rocky Mountains, the province has a diverse geography, with rugged landscapes that ...
resulted in the discovery of trace
DNA Deoxyribonucleic acid (; DNA) is a polymer composed of two polynucleotide chains that coil around each other to form a double helix. The polymer carries genetic instructions for the development, functioning, growth and reproduction of al ...
evidence linked to twenty-six missing women. The heads, hands, and feet of two of the missing women were eventually found. ''Protophormia terraenovae'' larvae were prominent on these remains. Forensic entomologists determined developmental rates based on locally collected specimens of ''P. terraenovae'', and with this information, concluded that both women had been exposed for weeks prior to being frozen. The pig farmer and co-owner of the grounds, Robert “Willie” Pickton, was charged with the murders of all twenty-six women. In December 2007 Pickton was convicted of second-degree murder in the deaths of six women and stands accused of first-degree murder in the deaths of twenty other women.


Current and future research

Investigation of the species is still ongoing: specifically, researchers are examining PMI and ADH/ADD for ''P. terraenovae'',
ecdysteroid Ecdysteroids are arthropod steroid hormones that are mainly responsible for molting (ecdysis), development and, to a lesser extent, reproduction; examples of ecdysteroids include ecdysone, 20-hydroxyecdysone (ecdysterone), turkesterone and 2- ...
levels and molting, and adult
diapause In animal dormancy, diapause is the delay in development in response to regular and recurring periods of adverse environmental conditions.Tauber, M.J., Tauber, C.A., Masaki, S. (1986) ''Seasonal Adaptations of Insects''. Oxford University Press It ...
with reactions to certain temperatures.Numata, Hideharu and Sakiko Shiga. “Induction of Adult Diapause by Photoperiod and Temperature in ''Protophormia terraenovae'' (Diptera: Calliphoridae) in Japan” ''Environmental Entomology'' 24.6 (1995): 1633-1636. Microlesions were made inside the brain of ''Protophormia terraenovae'' to study the diapause factor. Results show that secretory
neurons A neuron (American English), neurone (British English), or nerve cell, is an membrane potential#Cell excitability, excitable cell (biology), cell that fires electric signals called action potentials across a neural network (biology), neural net ...
are necessary for entering the reproductive diapause. Other research based on the
haemolymph Hemolymph, or haemolymph, is a fluid, similar to the blood in invertebrates, that circulates in the inside of the arthropod's body, remaining in direct contact with the animal's tissues. It is composed of a fluid plasma in which hemolymph ce ...
circulation rate suggests that sensory-induced changes can result in a series of
gustatory The gustatory system or sense of taste is the sensory system that is partially responsible for the perception of taste. Taste is the perception stimulated when a substance in the mouth reacts chemically with taste receptor cells located on tas ...
stimulations that shorten the
cardiac cycle The cardiac cycle is the performance of the heart, human heart from the beginning of one heartbeat to the beginning of the next. It consists of two periods: one during which the heart muscle relaxes and refills with blood, called diastole, fo ...
of ''P. terraenovae''.


References

{{Taxonbar, from=Q7252086 Calliphoridae Insects described in 1830 Insects of the Arctic