Paleoleishmania
Encyclopedia
Paleoleishmania is an extinct genus
of kinetoplastid
(class Kinetoplastida), a monophyletic group of unicellular parasitic flagellate
protozoa
and at present it's placed in kinetoplastid family Trypanosomatidae. The genus contains two species
, Paleoleishmania neotropicum and the type species Paleoleishmania proterus.
The genus is known from the Albian
aged, Burmese amber deposits of northern Myanmar
and the Burdigalian
aged Dominican amber
deposits on the island of Hispaniola
.
The genus name Paleoleishmania is derived from the Greek
paleo meaning "old" and leishmania referencing the modern Leishmaniasis
-causing genus Leishmania
. All trypanosomes are heteroxenous (requiring more than one obligatory host in order to complete life cycle) or are transmitted through some variation of a vector.
and Robert Poinar in the journal Protist from Amastigotes, promastigotes and paramastigotes preserved with a blood engorged female sandfly
preserved in amber. The species was named Paleoleishmania proterus and the genus was erected for fossil digenetic trypanosomes. P. proterus was the first kinetoplastid
to be described from the fossil record.
specimen, number # P-3–5, amastigotes and paramastigotes associated with the species host, a relatively complete female sandfly of the species Lutzomyia adiketis
. P. neotropicum and L. adiketis are preserved in a polished piece of amber 18 by and 2 millimetre (0.078740157480315 in) thick. The amber specimen is currently residing in the Poinar Amber Collection housed at the Oregon State University
in Corvallis, Oregon
. Poinar published his 2008 type description in the journal Parasites & Vectors
. During the fly's struggle to escape from the resin, the alimentary tract was ruptured and some P. neotropicum flagellates leaked from there into the hemocoel. P. neotropicum and L. adiketis lived in an environment similar to modern moist tropical rain forests.
The morphology of the compact kinetoplast
, nucleus
, and rear-facing flagellum
indicate the species belongs in the family Trypanosomatidae. The preserved amastigotes are between 4 to 7 µm and their presence in the fly indicates the digenetic nature of the species. That the species is digenetic excludes the Blastocrithidia as a possible genus placement for the species, while Endotrypanum is specific to sloths which are not known on Hispaniola past the Quaternary
. The genus Phytomonas is excluded due to it being exclusively found in Hemiptera
ns. The paramastigotes range in size from 6 to 10 µm which is within the range for modern Leishmania species. There are several possible origins for the paramastigotes preserved in the proboscis. They probably developed within the proboscis from an earlier meal of the fly, however they may have been "infective promastigotes" which occur naturally in the mouthparts of some Lutzomyia' species. Though they are currently placed in the same genus, Dr. Poinar notes the likelihood that the two species arose interdependently from each other. It is possible P. neotropicum is the ancestor of one or more Neotropical Leishmania clades.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of kinetoplastid
Kinetoplastid
The kinetoplastids are a group of single-cell flagellate protozoa, including a number of parasites responsible for serious diseases in humans and other animals, as well as various forms found in soil and aquatic environments...
(class Kinetoplastida), a monophyletic group of unicellular parasitic flagellate
Flagellate
Flagellates are organisms with one or more whip-like organelles called flagella. Some cells in animals may be flagellate, for instance the spermatozoa of most phyla. Flowering plants do not produce flagellate cells, but ferns, mosses, green algae, some gymnosperms and other closely related plants...
protozoa
Protozoa
Protozoa are a diverse group of single-cells eukaryotic organisms, many of which are motile. Throughout history, protozoa have been defined as single-cell protists with animal-like behavior, e.g., movement...
and at present it's placed in kinetoplastid family Trypanosomatidae. The genus contains two species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
, Paleoleishmania neotropicum and the type species Paleoleishmania proterus.
The genus is known from the Albian
Albian
The Albian is both an age of the geologic timescale and a stage in the stratigraphic column. It is the youngest or uppermost subdivision of the Early/Lower Cretaceous epoch/series. Its approximate time range is 112.0 ± 1.0 Ma to 99.6 ± 0.9 Ma...
aged, Burmese amber deposits of northern Myanmar
Myanmar
Burma , officially the Republic of the Union of Myanmar , is a country in Southeast Asia. Burma is bordered by China on the northeast, Laos on the east, Thailand on the southeast, Bangladesh on the west, India on the northwest, the Bay of Bengal to the southwest, and the Andaman Sea on the south....
and the Burdigalian
Burdigalian
The Burdigalian is, in the geologic timescale, an age or stage in the early Miocene. It spans the time between 20.43 ± 0.05 Ma and 15.97 ± 0.05 Ma...
aged Dominican amber
Dominican amber
Dominican amber is amber from the Dominican Republic. Resin from the extinct species Hymenaea protera is the source of Dominican amber and probably of most amber found in the tropics....
deposits on the island of Hispaniola
Hispaniola
Hispaniola is a major island in the Caribbean, containing the two sovereign states of the Dominican Republic and Haiti. The island is located between the islands of Cuba to the west and Puerto Rico to the east, within the hurricane belt...
.
The genus name Paleoleishmania is derived from the Greek
Greek language
Greek is an independent branch of the Indo-European family of languages. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. Its writing system has been the Greek alphabet for the majority of its history;...
paleo meaning "old" and leishmania referencing the modern Leishmaniasis
Leishmaniasis
Leishmaniasis is a disease caused by protozoan parasites that belong to the genus Leishmania and is transmitted by the bite of certain species of sand fly...
-causing genus Leishmania
Leishmania
Leishmania is a genus of Trypanosomatid protozoa, and is the parasite responsible for the disease leishmaniasis. It is spread through sandflies of the genus Phlebotomus in the Old World, and of the genus Lutzomyia in the New World. Their primary hosts are vertebrates; Leishmania commonly infects...
. All trypanosomes are heteroxenous (requiring more than one obligatory host in order to complete life cycle) or are transmitted through some variation of a vector.
Paleoleishmania proterus
The genus was described in 2004 by George Poinar, Jr.George Poinar, Jr.
George O. Poinar, Jr. is an entomologist and writer. He is known for popularizing the idea of extracting DNA from insects fossilized in amber, an idea which received widespread attention when adapted by Michael Crichton for the book and movie Jurassic Park.Poinar earned a B.S. and M.S. at Cornell...
and Robert Poinar in the journal Protist from Amastigotes, promastigotes and paramastigotes preserved with a blood engorged female sandfly
Sandfly
thumb|Sandfly biting a human's little fingerthumb|Sandfly biteSandfly is a colloquial name for any species or genus of flying, biting, blood-sucking Dipteran encountered in sandy areas...
preserved in amber. The species was named Paleoleishmania proterus and the genus was erected for fossil digenetic trypanosomes. P. proterus was the first kinetoplastid
Kinetoplastid
The kinetoplastids are a group of single-cell flagellate protozoa, including a number of parasites responsible for serious diseases in humans and other animals, as well as various forms found in soil and aquatic environments...
to be described from the fossil record.
Paleoleishmania neotropicum
Paleoleishmania neotropicum is known solely from the holotypeHolotype
A holotype is a single physical example of an organism, known to have been used when the species was formally described. It is either the single such physical example or one of several such, but explicitly designated as the holotype...
specimen, number # P-3–5, amastigotes and paramastigotes associated with the species host, a relatively complete female sandfly of the species Lutzomyia adiketis
Lutzomyia adiketis
Lutzomyia adiketis is an extinct species of sandflies in the moth fly subfamily Phlebotominae. L. adiketis is a vector of the extinct Paleoleishmania neotropicum and both species are solely known from early Miocene Burdigalian stage Dominican amber deposits on the island of Hispaniola.-History and...
. P. neotropicum and L. adiketis are preserved in a polished piece of amber 18 by and 2 millimetre (0.078740157480315 in) thick. The amber specimen is currently residing in the Poinar Amber Collection housed at the Oregon State University
Oregon State University
Oregon State University is a coeducational, public research university located in Corvallis, Oregon, United States. The university offers undergraduate, graduate and doctoral degrees and a multitude of research opportunities. There are more than 200 academic degree programs offered through the...
in Corvallis, Oregon
Corvallis, Oregon
Corvallis is a city located in central western Oregon, United States. It is the county seat of Benton County and the principal city of the Corvallis, Oregon Metropolitan Statistical Area, which encompasses all of Benton County. As of the 2010 United States Census, the population was 54,462....
. Poinar published his 2008 type description in the journal Parasites & Vectors
Parasites & Vectors
Parasites & Vectors is a peer-reviewed open-access medical journal published by BioMed Central. The journal publishes articles on the biology of parasites, parasitic diseases, intermediate hosts, vectors and vector-borne pathogens. Parasites & Vectors was established in 2008 as a merger of Filaria...
. During the fly's struggle to escape from the resin, the alimentary tract was ruptured and some P. neotropicum flagellates leaked from there into the hemocoel. P. neotropicum and L. adiketis lived in an environment similar to modern moist tropical rain forests.
The morphology of the compact kinetoplast
Kinetoplast
A kinetoplast is a disk-shaped mass of circular DNA inside a large mitochondrion that contains many copies of the mitochondrial genome. Kinetoplasts are only found in protozoa of the class Kinetoplastida...
, nucleus
Cell nucleus
In cell biology, the nucleus is a membrane-enclosed organelle found in eukaryotic cells. It contains most of the cell's genetic material, organized as multiple long linear DNA molecules in complex with a large variety of proteins, such as histones, to form chromosomes. The genes within these...
, and rear-facing flagellum
Flagellum
A flagellum is a tail-like projection that protrudes from the cell body of certain prokaryotic and eukaryotic cells, and plays the dual role of locomotion and sense organ, being sensitive to chemicals and temperatures outside the cell. There are some notable differences between prokaryotic and...
indicate the species belongs in the family Trypanosomatidae. The preserved amastigotes are between 4 to 7 µm and their presence in the fly indicates the digenetic nature of the species. That the species is digenetic excludes the Blastocrithidia as a possible genus placement for the species, while Endotrypanum is specific to sloths which are not known on Hispaniola past the Quaternary
Quaternary
The Quaternary Period is the most recent of the three periods of the Cenozoic Era in the geologic time scale of the ICS. It follows the Neogene Period, spanning 2.588 ± 0.005 million years ago to the present...
. The genus Phytomonas is excluded due to it being exclusively found in Hemiptera
Hemiptera
Hemiptera is an order of insects most often known as the true bugs , comprising around 50,000–80,000 species of cicadas, aphids, planthoppers, leafhoppers, shield bugs, and others...
ns. The paramastigotes range in size from 6 to 10 µm which is within the range for modern Leishmania species. There are several possible origins for the paramastigotes preserved in the proboscis. They probably developed within the proboscis from an earlier meal of the fly, however they may have been "infective promastigotes" which occur naturally in the mouthparts of some Lutzomyia' species. Though they are currently placed in the same genus, Dr. Poinar notes the likelihood that the two species arose interdependently from each other. It is possible P. neotropicum is the ancestor of one or more Neotropical Leishmania clades.