''Pseudothryptus multiseriatus'' is the only species of ''Pseudothryptus'', a genus of minute marsh-loving beetle in the subfamily Limnichinae. Initially described in 1923 as part of the large genus ''

Caccothryptus ''Caccothryptus'' is a genus of Limnichidae, minute marsh-loving beetles in the subfamily Limnichinae. The genus was formally established (Circumscription (taxonomy), circumscribed) by the entomologist David Sharp (entomologist), David Sharp in ...

'', it was redescribed in 2004 due to a number of physical differences with other Limnichidae, especially in its genitalia.

Taxonomy

''Pseudothryptus multiseriatus'' is the only species in the genus ''Pseudothryptus''; a genus of Limnichinae, a subfamily of the minute marsh-loving beetles (Limnichidae). Within Limnichinae it belongs to the "Mandersia group" of genera, alongside the large genus ''

'' and four other small genera— Euthryptus, Mandersia, Resachus, and Simplocarina. These genera share a number of physical features, such as a non-articulated

aedeagus An aedeagus ( or aedeagi) is a reproductive organ of male arthropods through which they secrete sperm from the testes during copulation (zoology), copulation with a female. It can be thought of as the insect equivalent of a mammal's penis, th ...

(male reproductive organ) without an articulated internal piece ("spiculum") within the median lobe; this distinguishes the genera from the genus '' Byrrhinus''. The

Afrotropical The Afrotropical realm is one of the Earth's eight biogeographic realms. It includes Sub-Saharan Africa, the southern Arabian Peninsula, the island of Madagascar, and the islands of the western Indian Ocean. It was formerly known as the Ethiopi ...

genera '' Tricholimnichus'' and '' Cyclolimnichus'' are close relatives of the ''Mandersia'' group, but lack some distinguishing characteristics in the

pronotum The prothorax is the foremost of the three segments in the thorax of an insect, and bears the first pair of legs. Its principal sclerites (exoskeletal plates) are the pronotum (dorsal), the prosternum (ventral), and the propleuron (lateral) on e ...

. The entomologist Harry George Champion described the species as ''Caccothryptus multiseriatus'' in 1923, alongside '' C. testudo'' and '' C. ripicola''. There is no

holotype A holotype (Latin: ''holotypus'') is a single physical example (or illustration) of an organism used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of s ...

of the species, although a male specimen in the collections of the

Natural History Museum, London The Natural History Museum in London is a museum that exhibits a vast range of specimens from various segments of natural history. It is one of three major museums on Exhibition Road in South Kensington, the others being the Science Museum (Lo ...

has been designated as the

lectotype In biology, a type is a particular specimen (or in some cases a group of specimens) of an organism to which the scientific name of that organism is formally associated. In other words, a type is an example that serves to anchor or centralizes ...

. In 2005, entomologists Carles Hernando and Ignacio Ribera reclassified ''C. multiseriatus'' into a new genus, ''Pseudothryptus'', due to a number of differences in its genitalia and minor external characteristics.

Description

''Pseudothryptus multiseriatus'' is a small beetle about in length. It has a very convex oval body, ranging from brown to dark brown. It has two layers 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 ...

on its

elytra An elytron (; ; : elytra, ) is a modified, hardened forewing of beetles (Coleoptera), though a few of the true bugs (Hemiptera) such as the family Schizopteridae are extremely similar; in true bugs, the forewings are called hemelytra (sometime ...

; a short layer within the punctures, and a very long and thick layer between the stripes of the elytra. Each elytron has thirteen rows of punctures, with smooth and shiny surface between these rows. Its head, slightly retracted into its

, is covered with coarse, dense punctures. It has long eleven-segment antennae, extending beyond the back of the pronotum, covered with fine setae. They can be differentiated through their genital characteristics, as the parameres of the aedeagus are laterally fused. In contrast to the related genera ''Mandersia'' and ''Euthryptus'', their aedeagus possesses a small grove along the apex of its median lobe, while the base of their

phallus A phallus (: phalli or phalluses) is a penis (especially when erect), an object that resembles a penis, or a mimetic image of an erect penis. In art history, a figure with an erect penis is described as ''ithyphallic''. Any object that symbo ...

is symmetrical. The beetle can be found in portions of northeastern India, including the states of

Sikkim Sikkim ( ; ) is a States and union territories of India, state in northeastern India. It borders the Tibet Autonomous Region of China in the north and northeast, Bhutan in the east, Koshi Province of Nepal in the west, and West Bengal in the ...

and

Assam Assam (, , ) is a state in Northeast India, northeastern India, south of the eastern Himalayas along the Brahmaputra Valley, Brahmaputra and Barak River valleys. Assam covers an area of . It is the second largest state in Northeast India, nor ...

References

Bibliography

* * {{Taxonbar, from=Q21230759 Byrrhoidea genera Beetles of Asia Limnichidae Endemic fauna of India Monotypic Elateriformia genera