''Endeavouria'' is a

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispec ...

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial n ...

of land planarians from the Pacific region. It contains a single species, ''Endeavouria septemlineata''.

Description

The genus ''Endeavouria'' is similar to other closely related genera, such as ''

Caenoplana ''Caenoplana'' is a genus of land planarians from Australia and New Zealand. Description The genus ''Caenoplana'' is characterized by having an elongate, cylindrical to sub-cylindrical body. The eyes are arranged along the body margins, crow ...

'' and '' Kontikia'', but can be differentiated by the narrower creeping sole and a thick layer of longitudinal muscle fibers beneath the ventral nerve plate. . ''Endeavouria septemlineata'' is a small land planarian, reaching about in length. The dorsal side may appear completely black at first sight, but a closer look reveals that it has a light-brown background. There are seven dark longitudinal stripes running along the body: one narrown dark-brown stripe, two lateral broad black stripes with diffuse margins, two paramarginal stripes and two marginal stripes. The dorsal color is visible between the median and lateral stripes and between the lateral and paramarginal stripes. The ventral side and the region between the paramarginal and marginal stripes is pale grey. The creeping sole is marked by numerous small dark spots. The several eyes are arranged in a single row along the body margins, being located over the marginal stripes. They are closer to each other in the anterior region and posteriorly they gradually become more spaced. The copulatory apparatus of ''E. septemlineata'' has a big ventral fold and a small intra-antral penis papilla.

Etymology

The name ''Endeavouria'' honors the flagship

HMS Endeavour HMS ''Endeavour'' was a British Royal Navy research vessel that Lieutenant James Cook commanded to Australia and New Zealand on his first voyage of discovery from 1768 to 1771. She was launched in 1764 as the collier ''Earl of Pembroke'' ...

commanded by James Cook in his first voyage of discovery to Australia and New Zealand. The specific epithet ''septemlineata'' (

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power ...

for "seven-striped") refers to the seven dark longitudinal stripes on the dorsum.

Origin and Distribution

The native place of ''Endeavouria septemlineata'' is still unknown. It was first found in

Hawaii Hawaii ( ; haw, Hawaii or ) is a state in the Western United States, located in the Pacific Ocean about from the U.S. mainland. It is the only U.S. state outside North America, the only state that is an archipelago, and the only ...

and later in several locations in Brazil. As all land planarians in the tribe Caenoplanini, it is most likely originally from somewhere in the Pacific region. In 2018, the species was recorded from

Tahiti Tahiti (; Tahitian ; ; previously also known as Otaheite) is the largest island of the Windward group of the Society Islands in French Polynesia. It is located in the central part of the Pacific Ocean and the nearest major landmass is Aust ...

French Polynesia )Territorial motto: ( en, "Great Tahiti of the Golden Haze") , anthem = , song_type = Regional anthem , song = "Ia Ora 'O Tahiti Nui" , image_map = French Polynesia on the globe (French Polynesia centered).svg , map_alt = Location of French ...

, on the base of a single specimen. The identification was confirmed by examination of external and internal anatomy and

DNA barcoding DNA barcoding is a method of species identification using a short section of DNA from a specific gene or genes. The premise of DNA barcoding is that by comparison with a reference library of such DNA sections (also called " sequences"), an indi ...

. In 2021, the species was found in Italy - that was its first record for Europe.

Ecology and behavior

Endeavouria septemlineata feeding on Rhinocricus millipede

Tumbling behavior of Endeavouria septemlineata

Specimens of ''E. septemlineata'' show a gregarious behavior, gathering in groups of tens of individuals that remain hidden in the leaf litter and under rocks or fallen logs during the day. They feed on several invertebrate groups, such as

arthropod Arthropods (, (gen. ποδός)) are invertebrate animals with an exoskeleton, a Segmentation (biology), segmented body, and paired jointed appendages. Arthropods form the phylum Arthropoda. They are distinguished by their jointed limbs and Arth ...

s and

mollusk Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is es ...

s, which they may hunt, but most of the time they feed on dead animals, thus being mainly scavengers. It has been demonstrated that in Brazil several native land planarians feed on the introduced ''E. septemlineata'', thus possibly controlling its spread as an

invasive species An invasive species otherwise known as an alien is an introduced organism that becomes overpopulated and harms its new environment. Although most introduced species are neutral or beneficial with respect to other species, invasive species adv ...

. When attacked by a predator, individuals of ''E. septemlineata'' quickly move away. The most frequent strategy to escape is by tumbling, a behavior where the planarian lifts its posterior end and bends it forward until it touches the substrate ahead of the anterior end. If part of the body is trapped by the predator, it may escape by performing

autotomy Autotomy (from the Greek ''auto-'', "self-" and ''tome'', "severing", αὐτοτομία) or self-amputation, is the behaviour whereby an animal sheds or discards one or more of its own appendages, usually as a self-defense mechanism to elude ...

References

{{Taxonbar, from=Q18591209 Geoplanidae