{{short description|Species of beetle}} {{Distinguish|harlequin cabbage bug}} {{Speciesbox | image = Acrocinus longimanus.jpg | image_caption = A harlequin beetle in its natural habitat | parent_authority = Illiger, 1806 | taxon = Acrocinus longimanus | authority = (Linnaeus, 1758) | synonyms = {{center|''Cerambyx longimanus''}} }}
The '''harlequin beetle''' ('''''Acrocinus longimanus''''') is a large and distinctly colored species of longhorn beetle from the Neotropics and the only member of the genus '''''Acrocinus'''''.<ref name=Zeh2003>{{cite journal |first1=David W. |last1=Zeh |first2=Jeanne A. |last2=Zeh |first3=Melvin M. |last3=Bonilla |title=Phylogeography of the giant harlequin beetle (Acrocinus longimanus) |journal=Journal of Biogeography |volume=30 |issue= 5|pages=747–753 |year=2003 |issn=0305-0270 |doi=10.1046/j.1365-2699.2003.00880.x|bibcode=2003JBiog..30..747Z |s2cid=62880221}}</ref>
It is given its English name because of the elaborate pattern of black, orange-red and greenish-yellow markings in both sexes;<ref name=Zeh2003/><ref name=Evans2000>{{cite book |last1= Evans|first1= Arthur V.|last2= Bellamy|first2= Charles L.|title= An inordinate fondness for beetles |url= https://books.google.com/books?id=ZZ_hfpMo8oAC|accessdate= 24 Jan 2011|year= 2000|publisher= University of California Press|isbn= 978-0-520-22323-3|page= 130}}</ref> despite this the beetle is quite well-camouflaged when perched on a lichen or fungus covered tree trunk.<ref name="britannicaentry">{{cite encyclopedia |author=((The Editors of Encyclopaedia Britannica)) |url=http://www.britannica.com/EBchecked/topic/708166/harlequin-beetle |title=Harlequin beetle |encyclopedia=Encyclopædia Britannica Online |year=2014 |access-date=20 July 2022}}</ref> The species name ''longimanus'' is a Latin word that refers to the extremely long forelegs (''manus'') of the large males, which are longer than the beetle's entire body.<ref name="britannicaentry"/> The head-and-body of this beetle measures {{cvt|4.3|to(-)|7.5|cm}} long.<ref name=GuzmanVasquez2020>{{cite journal| last1=Guzmán-Vásquez | first1=H.M. | last2=Sánchez-Garciá | first2=J.G. | year=2020 | title=New state records of the harlequin beetle, Acrocinus longimanus (Linnaeus, 1758) (Coleoptera: Cerambycidae), in Mexico | journal=The Pan-Pacific Entomologist | volume=96 | issue=2 | pages=75–78 | doi=10.3956/2020-96.2.75 | s2cid=220365383 }}</ref> The size and unusual appearance of the harlequin beetle has made it popular among insect collectors.<ref name=ukbeetles>{{cite web| title=Acrocinus longimanus (Linnaeus, 1758) | url=https://www.ukbeetles.co.uk/acrocinus-longimannus | publisher=ukbeetles.co.uk | access-date=4 August 2023 }}</ref> Although essentially harmless to humans, it may bite in self-defense with its strong mandibles.<ref name=Hequet1996>{{cite book| last=Hequet | first=V. | year=1996 | title=Longicornes de Guyane | publisher=Orstom, Silvolab | isbn=9782950968616 }}</ref>
==Taxonomy== The harlequin beetle was first scientifically described as ''Cerambyx longimanus'' by Linnaeus in the 10th edition of Systema Naturae in 1758. In 1806, it was moved to the newly coined genus ''Acrocinus'' by Illiger.<ref name=Monne2015>{{cite journal| last1=Monné | first1=M.A. | last2=Chaboo | first2=C.S. | year=2015 | title=Beetles (Coleoptera) of Peru: A Survey of the Families. Cerambycidae, Disteniidae, Vesperidae | journal=Journal of the Kansas Entomological Society | volume=88 | issue=1 | pages=34–120 | doi=10.2317/JKES1410.13.1 | s2cid=83575786 }}</ref> Although recent authorities have consistently recognized it as the only member of this genus, the relationship to other genera of longhorned beetles has not been clear: It has been disputed whether the tribe Acrocinini only should include the genus ''Acrocinus'' or it also include a few other genera. Recent authorities have often considered Acrocinini as monotypic, but an analysis of morphological characters indicates that ''Macropophora'' and ''Oreodera'' are sufficiently close to also be included in this tribe.<ref name=Souza2020>{{cite journal| last1=Souza | first1=D.d.S. | last2=Sepúlveda | first2=T.A. | last3=Marinoni | first3=L. | last4=Monné | first4=M.L. | year=2020 | title=Phylogenetic analyses provide new insights into systematics of the longhorned beetle tribe Acrocinini (Coleoptera: Cerambycidae: Lamiinae) | journal=Arthropod Systematics & Phylogeny | volume=78 | issue=1 | pages=17–27 | doi=10.26049/ASP78-1-2020-02 }}</ref>
Despite the very large distribution of the harlequin beetle, both morphological and genetic evidence supports its status as a single widespread species rather than a cryptic species complex.<ref name=Zeh2003/>
==Distribution and habitat== The harlequin beetle is found in tropical and subtropical parts of the Americas, ranging from Mexico, through Central and South America, south as far as northernmost Argentina (Corrientes and Misiones), southernmost Brazil (Rio Grande do Sul) and Paraguay.<ref name=GuzmanVasquez2020/><ref name=Monne2015/><ref name=GerardoValle2017>{{cite journal| last1=Valle | first1=Néstor Gerardo | last2=Chatellenaz | first2=Mario Luis | last3=Damborsky |first3=Miryam | year=2017 | title=Acrocinus longimanus (Linnaeus, 1758) (Coleoptera, Cerambycidae): first record from the province of Corrientes, Argentina | journal=Check List | volume=13 | issue=6 | pages=987–991 | doi=10.15560/13.6.987 | doi-access=free }}</ref> It also occurs on the Caribbean island nation of Trinidad and Tobago,<ref name=Zeh2003/><ref name=GerardoValle2017/> but a record from Barbados is considered erroneous.<ref name=Peck2009>{{cite journal| last=Peck | first=S.P. | year=2009 | title=The beetles of Barbados, West Indies (Insecta: Coleoptera): diversity, distribution and faunal structure | journal=Insecta Mundi | volume=0073 | pages=1–51 }}</ref> The harlequin beetle has been recorded from all Central American countries and all South American countries, except Chile and Uruguay.<ref name=GerardoValle2017/><ref name=Bretas2020>{{cite journal| last1=Bruno | first1=J. | last2=Souza Oliveira | first2=B.d. | year=2020 | title=Occurrence of Acrocinus longimanus (Linnaeus, 1758)(Coleoptera: Cerambycidae) in Montes Claros, Minas Gerais, Brazil | journal=Arthropods | volume=9 | issue=1 | pages=1–6 }}</ref> In Mexico, its distribution is incompletely known, but it is found in the south of the country, ranging north along the western side of the central plateau to Sinaloa and along the eastern side to San Luis Potosí.<ref>[https://www.inaturalist.org/taxa/126923-Acrocinus-longimanus iNaturalist records]</ref>
The harlequin beetle is locally common and while most records are from undisturbed forests, it also occurs in secondary forest and occasionally even in cities if there are green areas nearby.<ref name=Bretas2020/><ref name=Colorado2016>{{cite journal| last1=Colorado Z. | first1=G.J. | last2=Torres-Bejarano | first2=A.M. | year=2016 | title=New geographic distribution record of the phoretic association between the cerambycid beetle Acrocinus longimanus and the pseudoscorpion Cordylochernes scorpioides in the Colombian Amazonia | journal=Mundon Amazónico | volume=7 | issue=12 | pages=111–114 | doi=10.15446/ma.v7.63117 | doi-access=free }}</ref><ref name=PereiraColavite2017>{{cite journal| last1=Pereira-Colavite | first1=A. | last2=dos Santos | first2=W.E. | year=2017 | title=Ocorrência de Acrocinus longimanus (Linnaeus) (Coleoptera: Cerambycidae) em área urbana, Nordeste do Brasil | journal=EntomoBrasilis | volume=10 | issue=1 | pages=57–59 | doi=10.12741/ebrasilis.v10i1.664 | doi-access=free }}</ref> Most of its South American range is in the Amazon and Atlantic forests, but it also occurs more locally in the Cerrado and Caatinga,<ref name=Bretas2020/><ref name=PereiraColavite2017/> and in the northwestern part of the continent it occurs in both humid and fairly dry lowland and highland forests on both sides of the Andes, in interandean valles and the coastal Caribbean region.<ref name=CarvajalLV>{{cite web| last=Carvajal L. | first=V. | title=Los asombrosos cerambícidos gigantes del Ecuador | url=https://bibdigital.epn.edu.ec/bitstream/15000/21183/1/Ceramb_gigantes3.pdf | publisher=Escuela Politecnica Nacional, Departamento de Biología (Ecuador) | access-date=4 August 2023 }}</ref><ref name=Douglas2005>{{cite journal| last1=Douglas | first1=L.R. | last2=Salazar E. | first2=J.E. | year=2005 | title=Coleóptera (III). Sobre algunas localidades Colombianas para conocer y estudiar a Acrocinus longimanus (L.), y Euchroma gigantea (L.) (Coleoptera: Cerambycidae: Buprestidae) | journal=Museo de Historia Natural | volume=9 | pages=139–153 }}</ref><ref name=FuentesMario2018>{{cite journal| last1=Fuentes-Mario | first1=J.A. | last2=Salcedo-Rivera | first2=G.A. | year=2018 | title=Registro de Acrocinus longimanus (Linnaeus, 1758) (Coleoptera: Cerambycidae) en Sucre, Caribe Colombiano | journal=Revista Colombiana de Ciencia Animal | volume=10 | issue=1 | page=78 | doi=10.24188/recia.v10.n1.2018.634 | doi-access=free }}</ref> It has been recorded at elevations up to {{cvt|2150|m}} above sea level.<ref name=GuzmanVasquez2020/><ref name=Douglas2005/>
==Sexual dimorphism and behavior== {{multiple image | direction=horizontal | align=left | image1=Acrocinuslongimanus.JPG | total_width=300 | image2=Acrocinus longimanus MHNT femelle.jpg | footer=Male (left) and female (right) }}
Male and female harlequin beetles have similar color patterns and reach a similar body size, but the species is sexually dimorphic in the foreleg length and shape: In large males, the forelegs are greatly extended, up to {{cvt|15|cm|0}} long, being twice the length as in females with the same body size.<ref name=Zeh1992>{{cite journal |last1=Zeh |first1=David W. |last2=Zeh |first2=Jeanne A. |last3=Tavakilian |first3=Gerard |year=1992 |title=Sexual Selection and Sexual Dimorphism in the Harlequin Beetle ''Acrocinus longimanus'' |journal=Biotropica |volume=24 |issue=1 |pages=86–96 |doi=10.2307/2388476|jstor=2388476 |bibcode=1992Biotr..24...86Z }}</ref> Large males also exhibit strong curvature in their foreleg tibiae, which is not seen in females.<ref name=Zeh1992/> However, in small males, both length and shape of the forelegs resemble that seen in small females.<ref name=Zeh1992/> These traits aid the males as they fight with each other over optimal egg deposition sites in preparation for mating.<ref name=Zeh1992/> Males engage each other with their forelimbs in an attempt to flip other males off of the dead or dying trees that may be chosen by females to provide food for developing larvae.<ref name=Zeh1992/> The males also readily attempt to bite each other with their strong mandibles, sometimes biting off pieces of the opponents antennae or legs.<ref name=Zeh1992/> Once a site has been secured, the male will guard it around the clock, but females typically only are present during nighttime; once a female arrives, the male will also guard her.<ref name=Zeh1992/>
Harlequin beetles mainly fly during the night and appear to be able to rapidly locate recently fallen trees through the smell of the large amounts of sap that is released when it happens.<ref name=Zeh1992/> They are also attracted to artificial light during the night.<ref name=GuzmanVasquez2020/><ref name=Hequet1996/> The females prefer to lay their eggs on recently fallen trees, but may also use trees that have fallen up to a few months ago but not yet decayed, dead sections of living trees, or weakened living trees.<ref name=Douglas2005/><ref name=Zeh1992/> When using trees that are still alive, they are occasionally regarded as a pest,<ref name=PereiraColavite2017/><ref name=VeladoCano2012>{{cite web| last1=Velado-Cano | first1=M.A. | last2=Pablo-Cea | first2=J.D. | year=2012 | title=Impacto de escarabajo barrenador (Acrocinus longimanus) sobre los árboles de ojushte (Brosimum alicastrum) y el efecto indirecto sobre la población de monos araña (Ateles geoffroyi) en el Área Natural Protegida Chaguantique, Puerto El Triunfo, Usulután, El Salvador | url=https://cidoc.ambiente.gob.sv/documentos/impacto-de-escarabajo-barrenador-acrocinus-longimanus-sobre-los-arboles-de-ojushte-brosimum-alicastrum-y-el-efecto-directo-sobre-la-poblacion-de-monos-arana-ateles-geoffroyi-en-el-area-natural-p/ | publisher=University of El Salvador, Department of Natural History and Mathematics }}</ref> but otherwise harlequin beetles play an important role in the early phase of decomposition of dead wood, also creating habitats for other saproxylic species.<ref name=Zeh2003/> Mating and egg-laying mostly happens at dusk or dawn,<ref name=Zeh1992/> and a wide range of tree species are used, including ''Artocarpus'', ''Bagassa guianensis'', ''Brosimum alicastrum'' (breadnut) and others in the genus ''Brosimum'', ''Caryocar'' (souari trees), ''Castilla elastica'' (Panama rubber tree), ''Ceiba'', ''Clarisia'', ''Couma'', ''Enterolobium'', ''Eucalyptus'' (not native to the Americas but widely introduced), ''Ficus'' (fig trees), ''Guazuma'', ''Inga'', ''Lonchocarpus'', ''Maclura'', ''Parahancornia'', ''Perebea'', ''Persea'' and ''Theobroma cacao'' (cocoa tree).<ref name=GuzmanVasquez2020/><ref name=Monne2015/><ref name=GerardoValle2017/> The female uses her strong mandibles to make several circular, elliptical or crescent-shaped holes (diameter or maximum length {{cvt|1.5-4|cm|1|disp=sqbr}}) in the bark; the holes are typically placed at regular intervals and as if on a string, forming a distinct pattern on the tree.<ref name=Zeh1992/><ref name=VeladoCano2012/> The female places a single egg in each hole and she will typically lay 15–20 eggs over a period of several hours or a few days;<ref name="britannicaentry"/><ref name=Zeh1992/> a female may lay up to a total of 160 eggs.<ref name=CarvajalLV/> After an egg hatches, the wood is used as a food source by the larvae, which makes a network of tunnels inside it.<ref name=GerardoValle2017/><ref name=VeladoCano2012/> Just before pupating, the larvae can be around {{cvt|13|cm|0}} long.<ref name="britannicaentry"/> From the egg is laid to emergence from the wood as an adult beetle takes 4 to 12 months,<ref name=ukbeetles/><ref name=Zeh1992/> or possibly even up to 2 years.<ref name=CarvajalLV/> Although the harlequin beetle is very rarely maintained in captivity, it has been successfully raised and bred for several generations using either freshly cut wood from ''Morus'' (mulberry), or an artificially composite of ''Morus'' sawdust, a commercial mixture used for insect rearing and morin suspended in agar, as a larval food source.<ref>{{cite journal| last=Carter | first=J.L.S. | year=1998 | title=Captive rearing of the harlequin beetle (Coleoptera: Cerambycidae) at the Cincinnati Zoo, including use of an artificial larval diet | url=https://kb.osu.edu/bitstream/handle/1811/23770/V098N1_A06.pdf | journal=The Ohio Journal of Science | volume=98 | issue=1 | page=13 }}</ref>
The adult beetles can live up to about half a year, and they will feed on sap, wood, fungi and occasionally animal droppings.<ref name=Evans2000/><ref name=ukbeetles/> There is a level of seasonality in the species; adult beetles can be seen year-round, but they are most abundant in the first few months of the rainy season.<ref name=Zeh1992/>
==Relationship with pseudoscorpions== Tiny pseudoscorpions may attach themselves or hide under the wing coverts of harlequin beetles to use them for transport, which is a form of phoresy. In one case, fifteen pseudoscorpion had hidden themselves under the wing coverts of a harlequin beetle, but their combined weight was still less than 2.5% of the beetle's.<ref name=Colorado2016/> Some pseudoscorpion species appear to primarily, or exclusively, rely on harlequin beetles for dispersal between their habitats.<ref name="britannicaentry"/><ref name=Colorado2016/><ref name=Zeh1997>{{cite journal| last1=Zeh | first1=D.W. | last2=Zeh | first2=J.A. | last3=Bermingham | first3=E. | year=1997 | title=Polyandrous, sperm-storing females: carriers of male genotypes through episodes of adverse selection | journal=Proc. R. Soc. Lond. B | volume=264 | issue=1378 | pages=119–125 | doi=10.1098/rspb.1997.0018 | pmc=1688214 }}</ref> Once transported to a recently fallen tree by harlequin beetles, a new pseudoscorpion colony is formed and remains isolated until the next generation of harlequin beetles have completed their immature stages (egg, larvae and pupae) in the wood and emerge as adult beetles. At that point, pseudoscorpions from the colony will attach themselves to the emerging beetles to be transported to a new recently fallen tree, starting the cycle over again.<ref name=Zeh2003/><ref name=Zeh1997/>
==Anti-fungal properties== [[File:Arcocinus longimanus MHNT CUT 2014 14 1 Guyanne.jpg|thumb|Male - Beauchêne technique]] The harlequin beetle contains three homologous peptides, Alo-1, Alo-2, and Alo-3. Alo-3 was the first known peptide from insects to exhibit the knottin fold.<ref name="barbault">{{cite journal |title=Solution structure of Alo-3: A new knottin-type antifungal peptide from the insect ''Acrocinus longimanus'' |last1=Barbault |first1=Florent |last2=Landon |first2=Céline |last3=Guenneugues |first3=Marc |last4=Meyer |first4=Jean-Philippe |last5=Schott |first5=Valérie |last6=Dimarcq |first6=Jean-Luc |last7=Vovelle |first7=Françoise |journal=Biochemistry |year=2003 |volume=42 |issue=49 |pages=14434–14442 |doi=10.1021/bi035400o|pmid=14661954 |url=https://hal.archives-ouvertes.fr/hal-02422703/file/Format-2003_Biochemistry.pdf }}</ref> It has a higher level of activity against the fungal species ''Candida glabrata'' than the Alo-1 and Alo-2 peptides do.<ref name="barbault" /> Currently, there is a lack of treatment for fatal hospital-acquired infections and other pathologies. The peptide Alo-3 found in Harlequin beetles could provide a treatment for these severe, life threatening infections.<ref name="barbault" />
{{clear}} == References == {{Reflist}}
== External links == *{{Commons category-inline|Acrocinus longimanus|''Acrocinus longimanus''}}
{{Taxonbar|from=Q1418844}}
Category:Beetles described in 1758 Category:Beetles of South America Category:Lamiinae Category:Animal taxa named by Carl Linnaeus