Spirobolida is an

order Order, ORDER or Orders may refer to: * Categorization, the process in which ideas and objects are recognized, differentiated, and understood * Heterarchy, a system of organization wherein the elements have the potential to be ranked a number of ...

of "round-backed"

millipede Millipedes are a group of arthropods that are characterised by having two pairs of jointed legs on most body segments; they are known scientifically as the class Diplopoda, the name derived from this feature. Each double-legged segment is a re ...

s containing approximately 500 species in 12

families Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

. Its members are distinguished by the presence of a "pronounced suture that runs "vertically down the front of the head". Most of the species live in the

tropics The tropics are the regions of Earth surrounding the Equator. They are defined in latitude by the Tropic of Cancer in the Northern Hemisphere at N and the Tropic of Capricorn in the Southern Hemisphere at S. The tropics are also referred ...

, and many are brightly coloured. Mature males have two pairs of modified legs, the

gonopod Gonopods are specialized appendages of various arthropods used in reproduction or egg-laying. In males, they facilitate the transfer of sperm from male to female during mating, and thus are a type of intromittent organ. In crustaceans and millipe ...

s, consisting of the 8th and 9th leg pair: the posterior gonopods are used in sperm-transfer while the anterior gonopods are fused into a single plate-like structure. Aphistogoniulus jeekeli holotype gonopods 02

Aphistogoniulus jeekeli holotype gonopods 02

The families are divided into two suborders: Suborder Spirobolidea *

Allopocockiidae Allopocockiidae is a family of millipedes in the order Spirobolida. There are about five genera and eight described species in Allopocockiidae. Genera * ''Allopocockia'' Brolemann, 1913 * ''Anelus'' Cook, 1911 * ''Arolus'' Chamberlin, 192 ...

Atopetholidae Atopetholidae is a family of millipedes in the order Spirobolida Spirobolida is an order of "round-backed" millipedes containing approximately 500 species in 12 families. Its members are distinguished by the presence of a "pronounced suture ...

Floridobolidae ''Floridobolus'' is a genus of millipedes commonly known as Florida scrub millipedes containing three described species: ''Floridobolus penneri'', ''F. orini'', and ''F. floydi''; the latter two described in 2014. All three species are endemic t ...

Hoffmanobolidae Hoffmanobolidae is a family of millipedes belonging to the order Spirobolida Spirobolida is an order of "round-backed" millipedes containing approximately 500 species in 12 families. Its members are distinguished by the presence of a "pronou ...

Messicobolidae The family Messicobolidae is one of the smaller families of millipedes in the Order Spirobolida (fewer than 30 described species). In general appearance, messicobolids are medium to large size spirobolids and are often brightly colored. Messicob ...

Pseudospirobolellidae Pseudospirobolellidae, is a family of Round-backed millipedes of the order Spirobolida Spirobolida is an Order (biology), order of "round-backed" millipedes containing approximately 500 species in 12 family (biology), families. Its members ar ...

Rhinocricidae Rhinocricidae is a family of millipedes, that occurs disjunctly in Malesia and neighbouring parts of Australasia and in the Neotropics. The family contains the following genera: *'' Acladocricus'' Brölemann, 1913 *'' Alcimobolus'' Loomis, 1936 ...

Spirobolellidae Spirobolellidae is a family of millipedes in the order Spirobolida Spirobolida is an Order (biology), order of "round-backed" millipedes containing approximately 500 species in 12 family (biology), families. Its members are distinguished by t ...

Spirobolidae Spirobolidae is a family of millipedes in the order Spirobolida. The family consists of several genera with numerous species, and is commonly divided into the subfamilies Spirobolinae and Tylobolinae. Classification Subfamily Spirobolinae * '' ...

Typhlobolellidae Typhlobolellidae is a family of millipedes belonging to the order Spirobolida Spirobolida is an order of "round-backed" millipedes containing approximately 500 species in 12 families. Its members are distinguished by the presence of a "prono ...

Suborder Trigoniulidea *

Pachybolidae Pachybolidae, is a family of Round-backed millipedes of the order Spirobolida. The family includes 49 different genera. Two subfamilies recognized. Subfamilies *'' Pachybolinae'' *'' Spiromiminae'' Genera *'' Alluviobolus'' *'' Aphistogoniul ...

Trigoniulidae Trigoniulidae, is a family of round-backed millipedes of the order Spirobolida. The family includes 171 species belongs to 25 genera. Genera *'' Acanthiulus'' *'' Ainigmabolus'' *'' Apeuthes'' *'' Cairibolus'' *'' Chersastus'' *'' Cingalobolus ...

Select species

*''

Narceus americanus ''Narceus americanus'' is a large millipede of eastern North America. Common names include American giant millipede, worm millipede, and iron worm. It inhabits the eastern seaboard of North America west to Georgetown, Texas, north of the Ottine ...

'', a commonly seen species in eastern North America *''

Crurifarcimen vagans ''Crurifarcimen'' is a monotypic genus of millipedes containing the single species ''Crurifarcimen vagans''. Its common name is wandering leg sausage.Anadenobolus monilicornis ''Anadenobolus monilicornis'', known as the yellow-banded millipede or bumble bee millipede, is a species of millipede in the family Rhinocricidae. It is native to the Caribbean and has also been introduced to the southeastern United States. D ...

'', the Yellow-banded Millipede *''

Eucarlia ''Eucarlia'' is a genus of spirobolidan millipedes containing six species; most of which are endemic to the island nation of Seychelles, and one native to the Indonesian island of Sulawesi. Four of the Seychelles species have been assessed by t ...

'', a genus of threatened Indo-Pacific millipedes

References

External links

* * * Millipede orders Taxa named by Charles Harvey Bollman {{Myriapoda-stub