''Prostoma jenningsi'' is a
species of
ribbon worm
Nemertea is a phylum of animals also known as ribbon worms or proboscis worms, consisting of 1300 known species. Most ribbon worms are very slim, usually only a few millimeters wide, although a few have relatively short but wide bodies. Many h ...
known only from one site near
Croston,
Lancashire. It was described in 1971, and is believed to be the county's only
endemic species. It grows up to long, with 4–6 black eyespots, and has a long eversible proboscis.
Distribution
The only site where ''P. jenningsi'' has been found is a former
clay pit
A clay pit is a quarry or mine for the extraction of clay, which is generally used for manufacturing pottery, bricks or Portland cement. Quarries where clay is mined to make bricks are sometimes called brick pits.
A brickyard or brickworks is of ...
now used for
recreational fishing between
Bretherton and
Croston in
Chorley borough, Lancashire. It was discovered there in 1967, and described by Ray Gibson and Johnstone O. Young in 1971.
It is thought to be the only species endemic to Lancashire.
Prior to the discovery of ''P. jenningsi'', there had only been four reports of freshwater nemerteans in the
British Isles, in the
River Cherwell at
Oxford, the
River Cam
The River Cam () is the main river flowing through Cambridge in eastern England. After leaving Cambridge, it flows north and east before joining the River Great Ouse to the south of Ely, at Pope's Corner. The total distance from Cambridge to ...
at
Cambridge, a tank in
Regent's Park,
London, and the
Grand Canal at
Clondalkin,
County Dublin.
Description
''Prostoma jenningsi'' is a slender worm, with an elliptical cross-section. When young they are translucently white but take on a yellowish hue as they age, they then become a "dark yellowish or pale reddish-brown" as they age.
They are long when they hatch, reach their adult colouration above and can reach up to long as adults.
''P. jenningsi'' has 4–6 black
eyespots on the top of the head,
The eversible
proboscis is two-thirds to three-quarters of the body length, and is armed with one central
stylet and paired pouches each containing 2–5 accessory stylets.
''P. jenningsi'' is one of eleven species in the genus ''
Prostoma'', and can only be told from related species by
dissection
Dissection (from Latin ' "to cut to pieces"; also called anatomization) is the dismembering of the body of a deceased animal or plant to study its anatomical structure. Autopsy is used in pathology and forensic medicine to determine the cause o ...
. Uniquely, it has eleven
nerve
A nerve is an enclosed, cable-like bundle of nerve fibers (called axons) in the peripheral nervous system.
A nerve transmits electrical impulses. It is the basic unit of the peripheral nervous system. A nerve provides a common pathway for the e ...
s innervating the proboscis, rather than nine or ten, as seen in other species.
The
specific epithet
In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ...
' commemorates J. B. Jennings of the
University of Leeds, a scientist who studied invertebrate digestive physiology.
No
taxonomic synonyms are recognised.
Ecology
''Prostoma jenningsi'' lives among the vegetation at the edges of the pond, including plant species ''
Juncus effusus'', ''
Elodea canadensis
''Elodea canadensis'' (American waterweed or Canadian waterweed or pondweed) is a perennial aquatic plant, or submergent macrophyte, native to most of North America.Flora of North America''Elodea canadensis''/ref>Plants of British Columbia''Elod ...
'', ''
Myriophyllum spicatum
''Myriophyllum spicatum'' (Eurasian watermilfoil or spiked water-milfoil) is native to Europe, Asia, and north Africa, but has a wide geographic and climatic distribution among some 57 countries, extending from northern Canada to South Africa. It ...
'', ''
Phragmites communis'', ''
Potamogeton natans'' and ''
Typha latifolia''.
Its numbers vary in an
annual cycle
An annual cycle refers to a set of changes or events that uniformly, or consistently, take place at the same time of year.
In biology, the annual cycle for plants and animals details behavioral and chemical changes that take place as the seasons ...
, with smallest numbers when vegetation growth is highest.
References
Further reading
*
External links
*
{{Taxonbar, from=Q16247807
Tetrastemmatidae
Borough of Chorley
Environment of Lancashire
Animals described in 1971
Endemic fauna of England
1971 in England