tupinambis is a lizard genus which belongs to the family teiidae , and contains seven described species .

these large lizards are commonly referred to as tegus ( teiús in portuguese ) ; t. merianae ( argentine black and white tegu ) , t. rufescens ( red tegu ) , and t. teguixin ( gold tegu ) are popular in the pet trade .

they are primarily found in south america , although t. teguixin also occurs in panama .

tegus that have escaped or have been illegally released have adapted and are increasing in several florida counties including rural and suburban ( especially south miami-dade and hillsborough ) counties , agricultural areas ( especially homestead and unincorporated miami-dade county , florida ) and publicly owned conservation areas ( especially southern glades environmental and wildlife area and southeast margin of everglades national park ) of south florida see invasive species website ( www.ive-got-1.org ) for details with specific locations of credible observations and voucher specimens .

in 2012 a number of tegu species were reclassified from tupinambis to the previously used genus salvator .

the newly proposed classification comes from a restructuring of the teiidae family based upon the study of 137 morphological characteristics .

the new classification is as follows : salvator duseni ( yellow tegu ) , salvator rufescens ( red tegu ) , salvator merianae ( black and white tegu ) , tupinambis teguixin ( gold tegu ) , tupinambis longilineus ( rhondonia tegu ) , tupinambis palustris ( swamp tegu ) , tupinambis quadrilineatus ( four-lined tegu ) .

tupinambis

tupinambis longilineus avila - pires 1995 : 547 tupinambis longilineus — pianka & vitt 2003 : 200 tupinambis longilineus — harvey et al . 2012
maggie whitson marked
tupinambis merianae
as trusted on the
tupinambis merianae
page .
lacertus tupinambis lacépède 1788 salvator merianae duméril & bibron 1839 : 85 teius teguixim — gray 1845 : 16 tupinambis teguixin — boulenger 1885b : 335 tejus tejuexin — camp 1923 : 377 tupinambis rufescens — presch 1973 : 743 ( part ) tupinambis merianae — dirksen & de la riva 1999 tupinambis merianae — vrcibradic et al . 2011 salvator merianae — harvey et al . 2012 tupinambis merianae — avila et al . 2013 tupinambis merianae — crother et al . 2017 salvator merianae buzioensis ( müller 1968 ) tupinambis teguixin buzioensis müller 1968 tupinambis teguixin buzioensis — böhme 2010 salvator merianae buzioensis — harvey et al . 2012 ( by implication ) salvator merianae sebastiani ( müller 1968 ) tupinambis teguixin sebastiani müller 1968 tupinambis teguixin sebastiani — peters & orejas - miranda 1970 : 272 tupinambis teguixin sebastiani — böhme 2010 salvator merianae sebastiani — harvey et al . 2012 ( by implication )
lacerta teguixin linnaeus 1758 : 208 seps marmoratus laurenti 1768 : 59 laacerta tupinambis lacépède 1788 lacerta monitor — shaw & nodder 1790 : plate 21 lacerta monitor latreille 1801 : 220 tupinambis monitor daudin 1802 : 20 agama teguixin — link 1807 : 58 monitor meriani blainville 1816 monitor ( tutor ) americanus goldfuss 1820 : 168 teius monitor — wied 1824 tupinambis nigropunctatus spix 1825 : 18 monitor teguixin fitzinger 1826 podinema teguixin wagler 1830 lacerta teguixin — cuvier 1831 : 113 tupinambidibus daudini — ranzoni 1836 ( synonymy unclear ) teius teguixin — gray 1838 : 276 salvator nigropunctatus — duméril & bibron 1839 : 90 teius nigropunctatus — gray 1845 : 16 teius teguexim — bates 1864 : 233 podicnema teguixin — brühl 1886 tejus teguexin [ sic ] — dollo 1884 : 68 tejus tequexin [ sic ] — cope 1885 : 189 tupinambis teguixin — boulenger 1885 : 335 tupinambis nigropunctatus — boulenger 1885 : 337 tupinambis tegnixin [ sic ] — müller 1912 : 24 tupinambis teguixin — peters et al . 1970 : 272 tupinambis teguixin nigropunctatus — müller 1971 : 24 tupinambis teguixin nigropunctatus — mertens 1972 tupinambis teguixin — presch 1973 : 741 ( part ? ) tupinambis nigropunctatus — hoogmoed & lescure 1975 tupinambis teguixin — duellman 1978 : 223 tupinambis nigropunctatus — rese 1983 tupinambis teguixin — rese 1983 tupinambis teguixin — cei 1993 tupinambis teguixin — dirksen & de la riva 1999 tupinambis teguixin — mcnish 2011 tupinambis teguixin — harvey et al . 2012
macroscopic description of the limb muscles of tupinambis meriana . . . : ingenta connect
a new species of tupinambis daudin , 1802 ( squamata : teiidae ) from brazil .
reptilia , squamata , teiidae , tupinambis quadrilineatus : distribution extension and geographic distribution map .
a new species of tupinambis daudin , 1803 from southeastern brazil ( squamata , teiidae ) .
here we describe three cryptic species related to tupinambis teguixin on the basis of morphology and genetics .
primeira ocorrência de tupinambis quadrilineatus manzani , abe , 1997 ( squamata : teiidae ) no bioma amazônia .
hibernation and emergence pattern of tupinambis merianae ( squamata : teiidae ) in the taim ecological . . .
maggie whitson marked
file : téiu . jpg
as trusted on the
tupinambis merianae
page .
these findings expand the geographic distribution of tupinambis quadrilineatus is northwards , and encompass the the region between the states of piauí and maranhão , which is dominated by cerrado sensu strictu and / or forested patches of the cerrado–amazon ecotone . in this region , tupinambis quadrilineatus also occurs in syntopy with salvator merianae , which was previously classified as a member of the genus tupinambis .
maggie whitson marked the classification from
the reptile database
as preferred for
tupinambis merianae duméril & bibron 1839
.
maggie whitson marked
file : salvator merianae - necrophilia . jpg
as trusted on the
tupinambis merianae
page .
rese , r . 1983 . die grosstejus der gattung tupinambis . sauria 5 ( 2 ) : 15 - 17 - get paper here
road ecology blog : tegu lizard ( tupinambis merianae ) roadkill , south of capivari do sul , rio grande do sul , brazil .
right hemipenis of tupinambis quadrilineatus ( chnufpi 0036 ) . a sulcate surface b asulcate surface c lateral region . scale bar = 1 cm .
a new species of tupinambis ( squamata : teiidae ) from central brazil , with an analysis of morphological and genetic variation in the genus .
köhler , g . 1989 . tupinambis teguixin ( linnaeus , 1758 ) . sauria 11 ( 1 ) suppl . : 133–136 - get paper here
presch w ( 1973 ) a review of the tegus , lizard genus tupinambis ( sauria : teiidae ) from south america . copeia 4 : 740–746
comparisons . tupinambis teguixin is distinguished from the sympatric tupinambis cryptus sp . n . by two supraciliaries contacting the last supraocular ( three in t . cryptus sp . n ) ; usually three occipitals in contact with the interparietal ( usually one in t . cryptus sp . n ) . tupinambis teguixin differs from t . cuzcoensis sp . n . in having the first supraocular the longest ( the second is the longest in cuzcoensis ) ; first pair of chinshields are distinctly longer than the postmental ( in t . cuzcoensis sp . n . the first pair of chinshields are about as long or shorter than the postmental ) . tupinambis teguixin differs from tupinambis zuliensis sp . n . by having the first supraocular the longest ( the second is longest in t . zuliensis ) .
schreitmüller , w . 1924 . endotheliom bei tupinambis teguixin l . ( gemeiner teju . ) . archiv für naturgeschichte 90a ( 8 ) : 114 - 116
maggie whitson marked the classification from
species 2000 & itis catalogue of life : april 2013
as preferred for
tupinambis merianae duméril & bibron 1839
.
castro erde ; galetti m , 2004 . frugivory and seed dispersal by the tegu lizard tupinambis merianae ( reptilia : teiidae ) . ( frugivoria e dispersão de sementes pelo lagarto teiú tupinambis merianae ( reptilia : teiidae ) . ) papéis avulsos de zoologia ( sâo paulo ) , 44 ( 6 ) : 91 - 97 .
de castro er ; galetti m , 2004 . frugivory and seed dispersal by the tegu lizard tupinambis merianae ( reptilia : teiidae ) . ( frugivoria e dispersão de sementes pelo lagarto teiú tupinambis merianae ( reptilia : teiidae ) ) papéis avulsos de zoologia ( sâo paulo ) , 44 ( 6 ) : 91 - 97 .
the hemipenis of tupinambis quadrilineatus is also described here for the first time . the hemipenial morphology of teiid lizards is poorly known ( harvey et al . 2012 ) . cope ( 1896 ) analyzed the hemipenis of the genera dracaena , tupinambis , ameiva , and cnemidophorus and concluded that the morphology of these typical teiid species consist of numerous delicate , imbricate , transverse laminae , which are closely attached to one another . dowling and duellman ( 1978 , figure 83 . 2 ) published an illustration of the sulcate surface of the hemipenis of a species referred to as tupinambis nigropunctatus spix , 1825 , however they did not provide a museum number , nor did they describe the organ . presently , tupinambis nigropunctatus is considered as a synonym of tupinambis teguixin ( linnaeus , 1758 ) , and its drawing exihibited a slightly bilobed and relatively long hemipenis , with distal laminae . in addition , the hemipenial morphology of 13 teiid species was described by böhme ( 1988 ) , but the author did not examine nor describe the hemipenis of tupinambis .
müller , p . 1969 . über eine neue subspezies vom teju , tupinambis teguixin buziosensis n . ssp salamandra 5 ( 1 - 2 ) : 32 - 35 - get paper here
size . the largest tupinambis teguixin measured was a male , 279 mm svl with a 491 mm tail . the smallest was a neonate 84 mm svl and a 134 mm tail .
confusion over the use of tupinambis teguixin ( linnaeus ) and tupinambis nigropunctatus spix is a long standing problem and closely tied to the salvator merianae entanglement [ 10 ] . hoogmoed and lescure [ 19 ] and hoogmoed and gruber [ 20 ] considered lacerta teguixin linnaeus and tupinambis nigropunctatus spix distinct , but presch [ 21 ] considered them conspecific due to overlapping characters . the nomenclatural problems have been discussed and clarified by avil - pires [ 10 ] and we have little to add to her discussion . using photographs of type material , museum specimens and molecular analysis we conclude the following .
chamut s , jahn ga , arce oea , manes me ( 2012 ) testosterone and reproductive activity in the male tegu lizard , tupinambis merianae . herpetol conserv biol 7 ( 3 ) : 299–305
köhler , g . 1989 . lebensweise , haltung und nachzucht von tupinambis teguixin ( linnaeus 1758 ) ( sauria : teiidae ) . salamandra 25 ( 1 ) : 25 - 38 - get paper here
kiefer , mara cíntia & ivan sazima 2002 . diet of juvenile tegu lizard tupinambis merianae ( teiidae ) in southeastern brazil . amphibia - reptilia 23 ( 1 ) : 105 - 108 - get paper here
lema , thales de 1983 . bipedalia em tupinambis teguixin ( linneaeus , 1758 ) . ( suaria , teiidae ) . iheringia . série . zool . , porto alegre 62 : 89 - 119 - get paper here
lima , a . c . de ; pimenta , f . e . 2008 . reptilia , squamata , teiidae , tupinambis longilineus : distribution extension . check list 4 ( 3 ) : 240–243 - get paper here
the results of the cluster analysis [ s2a fig ] and pca [ s2b fig ] are in based on the genetic and morphological analyses describe above , we split the species currently recognized as tupinambis teguixin into four morphologically distinct species , three of which are new . considering the morphological data collected for this study , it is clear why these lizards have been confused for more than two centuries . differences are subtle , the coloration and pattern are variable , complex and have an ontogenetic component . table 1 summarizes the morphology for the four species of the tupinambis teguixin group discussed here , and table 2 compares the known species in the genus tupinambis .
few data are available on the morphology of the hemipenis of teiid lizards , especially those of the recently - defined genus tupinambis , a widely - distributed group of large - bodied lizards . this study provides an illustrated description of the hemipenis of tupinambis quadrilineatus , which is similar to that of other representatives of the tupinambinae subfamily . new records of the species from the state of piauí , in northeastern brazil , are also presented .
scale counts of the specimens of tupinambis quadrilineatus analyzed in the present study and the known range of values for the species , according to manzani and abe ( 1997 ) and colli et al . ( 1998 ) .
fitzgerald , lee a . , joseph a . cook and a . luz aquino 1999 . molecular phylogenetics and conservation of tupinambis ( sauria : teiidae ) . copeia 1999 ( 4 ) : 894 - 905 - get paper here
etymology ( genus ) : the generic name tupinambis is a masculine latin noun in the nominative singular apparently referring to the tupinambá indigenous tribe , one of several tupi ethnic groups that inhabited brazil at the time of the conquest .
benicio , ronildo alves ; gonçalves fonseca , mariluce 2014 . first record of tupinambis teguixin linnaeus , 1758 ( squamata : teiidae ) for the state of piauí , northeastern brazil cuad . herpetol . 28 : - get paper here
hagmann g . die eier von gonatodes humeralis , tupinambis nigropunctatus und caiman sclreops . 3 . beitrag zur kenntnis der lebens und fortpflanzungsweise der brazilianischen reptilien . zoo jahrb jenna , abt f syst . 1907 24 , 1906 307–316 .
unexpectedly , we found a substantial amount of confusion still exists between members of the tupinambis teguixin group and the salvator merianae group . müller [ 49 ] named t . teguixin sebastiani and t . t . buzioensis based on island populations in southeast brazil . böhme [ 50 ] recognized these as belonging to t . ( = salvator ) merianae , not t . teguixin , and reallocated the names appropriately . a recently published paper on exotic reptiles in the philippine pet trade lists tupinambis teguixin , however the accompanying photograph clearly shows a species of salvator [ 51 ] . fig 12 compares profiles of salvator merianae and tupinambis teguixin . data for the number of tupinambis teguixin group members involved in the novelty leather trade are apparently unknown . while large numbers of tegus are taken from the wild each year for the leather industry , most of these appear to be salvator merianae , or another member of the salvator clade . members of the tupinambis teguixin group are likely more often consumed as bush meat or enter the pet trade . the confusion between t . teguixin group members and s . merianae is on - going and basal to the confusion .
manzani , paulo roberto & abe , augusto shinya 2002 . a new species of tupinambis daudin , 1803 from southeastern brazil ( squamata , teiidae ) . arquivos do museu nacional rio de janeiro 60 ( 4 ) : 295 - 302
for this work we examined 335 extant museum specimens for morphological data [ s2 table ] . three previous works [ 8 , 10 , 18 ] provide detailed descriptions for tupinambis . however , some clarification as well as challenges regarding scale and scale arrangement terminology for tupinambis are needed . while we use the terms and characters provided in these papers , we made some adjustments . some scale counts and characters were found to contain information for distinguishing taxa , but most did not .
etymology . named cryptus for it similarity to tupinambis teguixin . on trinidad it is commonly known as the matte , on tobago it is called the salempenta . we propose the cryptic golden tegu as the common english name for this species .
péres jr ak ( 2003 ) sistemática e conservação de lagartos do gênero tupinambis ( squamata , teiidae ) . d . sc . thesis . brasília : universidade de brasília , programa de pós - graduação em biologia animal , p . 193
winck , g . r . and cechin , s . z . 2008 . hibernation and emergence pattern of tupinambis merianae ( squamata : teiidae ) in the taim ecological station , southern brazil . journal of natural history 42 : 239 - 247
distribution . tupinambis teguixin appears to be widespread in the amazon and present on the guiana shield , ranging from the caribbean coast of the guianas to roraima and para , brazil southward to mato grosso and goias and into western amazonas , brazil .
a lacerta teguixin paralectotype , the seps marmoratus holotype , and a tupinambis nigropunctatus paralectotype examined for this study all clearly lack the divided loreal , the small rows of granular scales between the supraoculars and ciliaries and the other traits associated with the genus salvator .
one of the two largest terrestrial lizards in the new world , the argentine black and white tegu , tupinambis merianae , is one of the seven currently recognized species of tegu lizards ( genus tupinambis , all south american ) . its sister species , the red tegu ( tupinambis rufescens ) rivals its size ; both can reach a total length of 145 cm ( 57 inches ) , with large heads and jaws . the argentine black and white tegu is an abundant species , found in a wide breadth of habitat types from ocean beaches to savannahs and disturbed areas such as forest edges , clearings , and roadsides up to elevations of 1250 m ( 4100 ft ) . it is a terrestrial animal but also a good swimmer ( embert et al . 2010 ; enge 2006 ) .
gols - ripoll , ariana ; emilio a . herrera & jazzmín arrivillaga 2015 . genetic structure of tupinambis teguixin ( squamata : teiidae ) , with emphasis on venezuelan populations rev . biol . trop . 63 ( 4 ) : 1235 - 1249 - get paper here
garcía - valdez , maría valeria ; silvia chamut , gonzalo valdez jaen , osvaldo e . a . arce , mario e . manes 2011 . dynamics of ovarian follicles in tupinambis merianae lizards . acta herpetologica 6 ( 2 ) : 303 - 313 - get paper here
kaiser , bernard w . , kimberly j . osorio , kevin m . enge and richard m . engeman . 2013 . tupinambis merianae ( argentine giant tegu ) ; pantherophis guttatus ( red cornsnake ) non - predatory killing . herpetological review 44 ( 2 ) : 329
vega parry , harold ; elisa vintiñi ; osvaldo e . a . arce ; mario e . manes 2009 . nutritional perfomance of tupinambis merianae lizards fed with corn starch as source of energy . acta herpetologica 4 ( 1 ) : 29 - 36 - get paper here
jansen , m . & g . köhler : reptilia , squamata , amphisbaenidae , amphisbaena cegei montero , 1997 , and reptilia , squamata , teidae , tupinambis rufescens ( günther , 1871 ) : vertical range extension . checklist 6 ( 4 ) : 503 - 504 .
examination of photographs of type material including one of the paralectotypes of lacerta teguixin linnaeus ( nrm 121 ) as well as seps marmoratus laurenti , and tupinambis nigropunctatus spix ( zma 629 ) allowed for some comparison of the type material to the data collected from the specimens examined .
type species : tupinambis monitor daudin 1802 is the type species of the genus tupinambis daudin 1802 . tupinambis is also the type species of the subfamily tupinambinae bonaparte 1831 ( not established by estes et al . 1988 as is often cited ; see costa et al . 2016 for historical details ) . distribution : not in uruguay ( m . hoogmoed , pers . comm . , 19 feb 2013 ) . not in panama fide lotzkat 2015 ( pers . comm . , 23 dec 2015 ) ; see map in silva et al . 2018 . nomenclature : the name t . teguixin was for a long time applied for the species here named t . merianae , while the species here under discussion was called t . nigropunctatus . for a detailed discussion of nomenclature see avila - pires ( 1995 ) . synonyms partly from cei 1993 .
gudynas , e . 1985 . notas sobre teiidos del uruguay ( lacertilia : teiidae ) , i . nuevos registros y distribución geográfica de tupinambis teguixin , teius teyou , cnemidophorus lacertoides y pantodactylus schreibersii schreibersii . centro de estudios don orione , contribuciones en biología 12 : 9 - 17 .
caldeira - costa , henrique ; são pedro , v . de a . ; péres , a . k . & neves feio , r . 2008 . reptilia , squamata , teiidae , tupinambis longilineus : distribution extension . check list 4 ( 3 ) : 267–268 - get paper here
juri , guadalupe lópez ; sergio naretto , ana carolina mateos , margarita chiaraviglio , and gabriela cardozo 2015 . influence of life history traits on trophic niche segregation between two similar sympatric tupinambis lizards south american j . herp . 10 ( 2 ) : 132 - 142 . - get paper here
althaus , r l . ; maunskas , g . ; gasparotti , < br / > m . l . l ; miouet a , c . 1994 . caracteristicas comestibles de la carne de tupinambis teguixin . bol . asoc . herp . argentina 10 ( 1 ) : 19 - 21
here , we provide a taxonomic revision to bring taxonomy into concordance with the molecular and morphological results for the tupinambis teguixin complex . the confusion of names presented in these lizards is discussed and illustrated in s3 , s3a and s3b fig . first , we provide a re - description of :
cecchetto , nicolas rodolfo ; naretto , sergio 2015 . do sex , body size and reproductive condition influence the thermal preferences of a large lizard ? a study in tupinambis merianae journal of thermal biology , doi : 10 . 1016 / j . jtherbio . 2015 . 09 . 001 - get paper here
first , the shape and size of the scales on the anterior surface of the femur : ( a ) t . cuzcoensis ; ( b ) t . cryptus ( c ) t . teguixin ( d ) t . zuliensis . second , the upper labial under the anterior corner of the orbit ( e , f ) . the inside corner of the orbit is over the third upper labial in tupinambis teguixin , and the fourth upper labial in t . cryptus . the supratemporals are numbered . tupinambis teguixin ( e ) usually has two supratemporals and t . cryptus ( f ) usually has three supratemporals .
silva , marcélia b . ; marco a . ribeiro - júnior , and teresa c . s . ávila - pires 2018 . a new species of tupinambis daudin , 1802 ( squamata : teiidae ) from central south america . journal of herpetology 52 ( 1 ) : 94 - 110 - get paper here
tupinambis cerradensis colli , péres & cunha , 1998 : 479 ( adult male holotype deposited in the coleção de herpetologia of the universidade de brasília , chunb 00468 , type - locality : rosário oeste , mato grosso , brazil ( 14°50 ' s , 56°25 ' w , sad69 ) , not examined ) .
( a ) importance of meristic counts in predicting individual assignments to four species of tupinambis lizards based on mean decrease in gini accuracy as revealed by 100 replicates of 10 - fold cross - validation of guided regularized random forests ( grrf ) . the higher the mean decrease in gini accuracy , the higher the predictor importance . ( b ) prediction error of grrf models based on reducing number of predictors ranked by importance , as revealed by 100 replicates of 10 - fold cross - validation . ( c ) variation in vertebral rows and scales around midbody , the two best predictors of differences among four species of tupinambis lizards .
tupinambis quadrilineatus manzani & abe , 1997 : 2 ( adult male holotype deposited in the museu de zoologia of the universidade estadual de campinas , zuec 1963 , type - locality : fazenda bandeirantes , municipalty of baliza , goiás , brazil ( 16°13 ' s , 51°25 ' w , sad69 ) , not examined ) .
seps marmoratus laurenti is most likely based upon zmb 849 [ 23 ] a juvenile specimen ( fig 3 ) . the name has long been considered a junior synonym of tupinambis teguixin . the dorsal pattern is composed of wide dark bands separated by narrow light bands and four rows of white spots on the dorsum . it has five supraoculars , first is the longest , the second is the largest in area and the last one contacts two ciliaries . also , it has 115 or 116 vertebral rows . all are in agreement with our clade two . here we retain this name as a junior synonym of tupinambis teguixin based upon the data we have .
moraes carvalho , andréa de ; ayrton klier péres júnior , maria auxiliadora andrade , and valéria de sá jayme 2013 . prevalence of enterobacteriaceae in tupinambis merianae ( squamata : teiidae ) from a captive facility in central brazil , with a profile of antimicrobial drug resistance in salmonella enterica . phyllomedusa 12 ( 1 ) : 57 - 67
adult male tupinambis quadrilineatus . a specimen collected in the palmares national forest , altos , piauí ( chnufpi 0036 ; scale 5cm ) b specimen collected with pit - fall traps at guadalupe , piauí ( chnufpi 0038 ) c lateral view of the head and d dorsal view of the anterior region of the body ( chnufpi 0036 ) .
tupinambis nigropunctatus spix was based upon five syntypes and all are extant . hoogmoed and gruber [ 20 ] designated zma 629 the lectotype , making zma 627 , 628 , 630 , 3208 paralectotypes . they note spix was unsure of his own classification when it came to distinguishing it from t . teguixin , and thought it to be either a different species or a female t . teguixin . vanzolini [ 25 ] interpreted the spix type locality to be belém , para , brazil . photos of zma 627 ( a male ) illustrate morphology that agrees relatively well with our clade two ( fig 4 ) . here we retain tupinambis nigropunctatus spix as a junior synonym of t . teguixin .
citation : murphy jc , jowers mj , lehtinen rm , charles sp , colli gr , peres ak jr , et al . ( 2016 ) cryptic , sympatric diversity in tegu lizards of the tupinambis teguixin group ( squamata , sauria , teiidae ) and the description of three new species . plos one 11 ( 8 ) : e0158542 . urltoken
species illustrated : top - tupinambis cuzcoensis sp . n . , clade 1 . photo credit mike pingleton . second from top t . teguixin , clade 2 . photo credit armida madngisa . bottom photo t . cryptus ( clade 4 ) . photo credit jcm . nodes with bayesian posterior probabilities ≥ 95 are represented by asterisks ( * ) .
there is considerable pattern variation in tupinambis cryptus . mainland venezuelan specimens tend to have bands that are indistinct and short longitudinal stripes that beebe [ 2 ] termed “dashes . ” a few are almost uniform in coloration . none of the adults from trinidad and tobago have this pattern , although we have seen a few individuals in the field with indistinct bands .
distribution . tupinambis cryptus is known from trinidad and tobago , venezuela , the guianas , and as far south as the confluence of the rio negro and rio branco in brazil , but its range may be more extensive . it ranges as far west as falcon , venezuela , and appears to range into the andes in the vicinity of bucaramango , colombia .
tupinambis quadrilineatus is endemic to the cerrado savannas of central brazil . the species was described in 1997 , based on four specimens from goiás , mato grosso , and tocantins ( manzani and abe 1997 , silveira 2009 ) . almost simultaneously , colli et al . ( 1998 ) described the same form under the junior - synonym tupinambis cerradensis . a number of other specimens were collected subsequently in the brazilian states of goiás , minas gerais , mato grosso , maranhão , tocantins , piauí , pará and the distrito federal ( barreto et al . 2007 , ferreira et al . 2009 , silveira 2009 , dal vechio et al . 2013 ) . the geographic range of the species is extended further in the present study .
chiarello , adriano g . ; srbek - araujo , ana c . ; del - duque jr . , hermano j . ; coelho , eduardo de r . ; rocha , carlos f . d . 2010 . abundance of tegu lizards ( tupinambis merianae ) in a remnant of the brazilian atlantic forest . amphibia - reptilia 31 ( 4 ) : 563 - 570 - get paper here
the emergence period and winter aggregations of a population of tupinambis merianae from southern brazil as well as some behavioural aspects from its post‐emergence period are examined . fifty‐six individuals were captured and marked in 64 days ( 640 h ) of field study . most of the hibernacula identified were beneath human constructions . the first individuals emerged in august and the last active . . . [ show full abstract ]
tupinambis is distributed from the chocó of colombia eastward to northern venezuela , ( including the isla de margarita , trinidad and tobago ) and the guianas southward into amazonia , and the cerrados of eastern bolivia [ 8 ] . three of the four species , tupinambis longilineus [ 10 ] , t . palustris [ 11 ] , and t . quadrilineatus [ 12 ] have poorly understood distributions centered in brazil . one species , t . longilineus , is known to use open , sub - montane tropical rainforest along rivers as well as disturbed areas . another , t . palustris is apparently restricted to wetlands in the vicinity of the type locality at usina hidréletrica três irmãos , in the lower tiete river , between aracatuba and pereira barreto in the state of são paulo , brazil . tupinambis quadrilineatus is endemic to the savannas of central brazil [ 13 , 14 , 15 ] , however langstroth [ 16 ] suggested it may also occur in bolivia . these three species have all been described since 1995 . the range of t . teguixin is thought to overlap the distribution of all three congeners , and has a range that encompasses that of the entire genus , or nearly so [ 8 ] .
passos , d . c . ; f . lima - araujo ; a . c . b . melo ; d . m . borges - nojosa . 2013 . new state record and distribution extension of the golden tegu tupinambis teguixin ( linnaeus , 1758 ) ( squamata : teiidae ) to the caatinga biome , northeastern brazil . check list 9 ( 6 ) : 1524 - 1526 - get paper here
fig 1 illustrates some of the varied patterns and coloration present in the tupinambis teguixin group . here , we present a range - wide analysis of molecular and morphological data , strongly supporting the existence of four species - level taxa within what is currently considered t . teguixin . morphological data suggest the potential presence of additional species . we discuss the phenomenon and impact of cryptic , widespread species , and offer perspectives for future research .
tupinambis quadrilineatus ; taylor 2003 : 44 , langstroth 2005 : 106 , silva jr . et al . 2005 : 81 , vitt et al . 2005 : 8 , werneck and colli 2006 : 1987 , guimarães et al . 2007 : 353 , recoder and nogueira 2007 : 270 , silveira 2009 : 442 , ferreira et al . 2009 : 355 , moreira et al . 2009 : 187 , recoder et al . 2011 : 275 .
the genus tupinambis contained seven species until harvey et al . [ 8 ] revalidated salvator duméril and bibron for s . duseni , s . merianae , and s . rufescens . the generic split was subsequently supported by molecular work [ 9 ] . salvator inhabits much of south america east of the andes , and they share a suite of traits ( a complete row of supraocular granules , divided caudal annuli alternating with complete annuli , a round pupil , keeled proximal subcaudals , and usually a divided loreal ) distinguishing them from the sometimes sympatric tupinambis . thus , four species , t . longilineus , t . palustris , t . quadrilineatus , and t . teguixin , remain in daudin’s genus . one of these , t . palustris , is poorly known and its status seems uncertain . two of us ( grc , ap ) are currently working to clarify its relationship to the other species in the genus .
natural history . because this species has been long confused with other species of the t . teguixin group comments on its natural history are difficult to make because they are deeply entangled in the literature with the other cryptic species in the group as well as members of the genus salvator . considering that tupinambis teguixin and t . cryptus sp . n . have been collected within 3 km of each other further investigation of these taxa would be of ecological interest .
tupinambis quadrilineatus : maranhão : mpeg 16817 ( rio matões , right bank tributary of the rio balsas , balsas ) , mpeg 30140 ( são raimundo das mangabeiras ) , piauí : chnufpi 0036 ( palmares national forest , altos ) , chnufpi 0037 ( monsenhor gil ) , chnufpi 0038 ( fazenda são pedro , guadalupe ) , mpeg 16845 ( lagoa alegre ) , mpeg 30139 ( ribeiro gonçalves ) , mpeg 30141 ( estação ecológica de uruçuí - una , uruçuí ) .
comparisons . tupinambis zuliensis sp . n . can be distinguished from t . teguixin and t . cryptus by having the second supraocular the longest and the largest in area ( the other two species have the first supraocular the longest and the second is largest in area ) . it can be distinguished from t . cuzcoensis by having the post mental longer than the first pair of chin shields ( it is shorter than the first pair of chin shields in t . cuzcoensis ) .
with a maximum body length of 400 mm [ 8 ] , tupinambis teguixin is one of the largest terrestrial , and as previously noted one of the most exploited , neotropical lizards . yet , its systematics and nomenclature remain poorly resolved , with some authors [ 3 ] describing the taxonomy as “tortuous . ” discussing genetic data fitzgerald et al . [ 3 ] wrote , “…the split among t . teguixin from cuyabeno , ecuador and roraima , brazil was comparable to differences between t . teguixin and t . longilineus and even to that between t . rufescens and t . merianae . ” this would be expected in species composed of multiple lineages and given the two localities are separated by more than 1500 km . however , tupinambis teguixin has been used in hundreds of phylogenetic , ecological , morphological , and physiological studies given its abundance , size , and availability in museum collections and the pet trade , without the systematic work to clarify the status of various populations .
we gathered tissue samples from existing museum collections from 40 tupinambis and salvator , including 31 t . teguixin . using standard pcr and sanger - sequencing methods , we sequenced fragments of three mitochondrial genes ; the 12s rdna using primers 12sa 5′ - aaactgggattagataccccactat - 3′ and 12sb 5′ - gagggtgacgggcggtgtgt - 3′ from kocher et al . [ 26 ] , 16s rdna using primers 16sl : 5′ - gcctgtttatcaaaaacat - 3′ and 16sh 5′ - ccggtctgaactcagatcacgt - 3′ from palumbi et al . [ 27 ] , and nd4 using primers nd4 5’ cac cta tga cta cca aaa gct cat gta gaa gc 3’ and leu 5’ cat tac ttt tac ttg gaa ttt gca cca 3’ from arévalo et al . [ 28 ] . these data were combined with all available , vouchered individuals from genbank for those genes for crocodilurus , dracaena , tupinambis , and salvator , representing the subfamily tupinambinae , with callopistes representing callopistinae , following harvey et al . [ 8 ] and ameiva ameiva as the outgroup .
anecdotally , an internet search for photographs of tupinambis teguixin produces nearly as many photographs of salvator merianae labeled t . teguixin as it does t . teguixin photographs . websites such as the encyclopedia of life , i - naturalist , and the reptile database have photographs of both s . merianae and the t . teguixin group labeled t . teguixin . the confusion of these two tegu lizards has been on - going for centuries and carries into their life history descriptions and ultimately into conservation polices .
the bayesian inferences ( bi ) analyses converged very quickly , with psrf ~ 1 . 0 and ess > 200 for all parameters . our results are similar to previous phylogenies of tupinambinae [ 3 , 9 , 41 ] . the subfamily is strongly supported as monophyletic ( pp = 100 ) , as are the genera callopistes ( 100 ) , salvator ( 100 ) and tupinambis ( 98 ) . the placement of the genera dracaena and crocodilurus is not strongly supported , likely due to the small amount of mitochondrial data available for those species . we find weak support for a clade consisting of , respectively , dracaena , crocodilurus , and tupinambis . we also find strong support for all sampled species , with possible paraphyly of s . rufescens , which includes two specimens of s . duseni [ 3 ] , though this could potentially be specimen mis - identification . multi - locus nuclear datasets and deeper phylogeographic investigation will be needed to resolve deeper relationships in tupinambinae and species limits in salvator .
tupinambis teguixin has been given two common names , the golden tegu ( t . teguixin and t . cryptus ) and the black and white tegu . salvator merianae is also mostly black and white [ 18 ] . the two species of golden tegus , t . teguixin and t . cryptus , both have adult patterns of black , brown and gold / yellow / white , with adult male t . teguixin tending to be darker than t . cryptus males based upon our relatively small sample of live specimens .
natural history . the co - occurrence of this species with t . teguixin on the guiana shield suggests the previous natural history accounts [ 2 ] are likely a mixture of these two species . however , t . teguixin is unknown from trinidad and tobago and natural history descriptions from the islands’ populations can be attributed to t . cryptus alone . our observations of this lizard suggest they use secondary forest , savannas , and human modified habitats . we have not observed them in primary forests proper , but at the forest edge . it may avoid dense forest because of the reduced number of basking sites . like other species of tupinambis , t . cryptus is a dietary generalist . we have observed this lizard investigating caiman nests , foraging along streams on the floor of secondary forests and in mangroves . usually their tongue is flicking and they are probing the leaf litter with their head . tupinambis cryptus is most readily observed foraging under the bird feeders at the asa wright nature center ( trinidad ) were they scavenge pieces of fruit .
tupinambis teguixin and t . cryptus eggs incubate until the first heavy rains in june or july . incubation time is thus on the order of 150–180 days compared to incubation times of about 60 days in salvator merianae which places its nests in the ground [ 57 ] . there is some anecdotal evidence that female t . teguixin group members may use communal nests and that the incubation time of eggs laid in captivity may be as long as 170 days which supports the 150–180 incubation period suspected in nature [ 10 ] .
five tupinambis quadrilineatus specimens were examined in the collection of the goeldi museum . in 1993 , specimen mpeg 16817 was collected in balsas , maranhão ( reported by barreto et al . 2007 ) , and specimen mpeg 16845 was captured in the municipality of lagoa alegre , piauí . in 2009 , three specimens were collected during the parnaiba project in ribeiro gonçalves ( mpeg 30139 ) , and uruçuí ( mpeg 30141 ) , in the state of piauí , and são raimundo das mangabeiras ( mpeg 30140 ) , in maranhão .
the two species have been long confused in the literature . both specimens were in the pet trade and are from unknown localities . diagnostic characters are obvious . a . tupinambis teguixin lacks granular scales separating the supraoculars from the ciliaries , it has a single loreal scale , and the head is slightly compressed ( dorsoventrally ) . b . salvator merianae has granular scales between the supraocualars and the cillaries , a divided loreal , and a deep head . also note the tall and horizontally divided lower labials . photographs by jcm .
the grrf analyses indicated that prediction accuracy ranged from 13 % , when using the single most important predictor , to 7 % , when using all predictors ( fig 9a ) . vertebral rows and scales around midbody were the best predictors of the four species , with a prediction accuracy around 87 % based on 100 replicates of 10 - fold cross - validation ( fig 9b ) . with the exception of tupinambis zuliensis , which was represented by only four individuals , these two variables permit a fairly good separation of the three other species ( fig 9c ) .
tegu lizard ( tupinambis merianae ) belongs to the teiidae family . it is distributed throughout the americas , with many species , including brazilian ones . they are from the tupinambis genus , the largest representatives of the teiidae family . for this study three animals ( run over ) coming from donation were used . the dissected lizards were fixed in 10 % , formaldehyde , and the macroscopic analysis was carried out in a detailed and photo documented way , keeping the selected structures “in situ” . this paper had as its main aim contributing to the macroscopic description of the chest myology , as well as the thoracic and pelvic limbs of the lizard t . merianae . the results obtained from this research were compared to authors who have studied animals from the same reptilia class . thus , we conclude that our macroscopic results are similar to those already described by the researchers hildebrand ( 1995 ) , moro and abdala ( 2004 ) and abdala and diogo ( 2010 ) . we should highlight that the knowledge on anatomy has importance and applications to various areas within biology , contributing in a substantial way to the areas of human health and technology .
tupinambis cuzcoensis is the most basal clade and its andean foothills—western amazon distribution suggests the andean uplift may have been involved in its origin . the rise of the mérida andes likely isolated t . zuliensis from the other populations and the eastward shifts of the orinoco river are likely to have influenced the evolution of the t . cryptus and t . teguixin . the absence of t . teguixin in venezuela may suggest that the orinoco or a marine incursion separated the eastern and western populations and allowed speciation with the subsequent eastward dispersal of t . cryptus to the guyanas and brazil .
known localities for tupinambis quadrilineatus in brazil . distrito federal ( df ) : brasília , gama ( 1 ) . goiás ( go ) : iaciara ( 2 ) minaçu ( 3 ) mara rosa ( 4 ) santa terezinha de goiás ( 5 ) pirenópolis ( 6 ) aragarças ( 7 ) baliza ( 8 ) . maranhão ( ma ) : balsas ( 9 ) são raimundo das mangabeiras ( 10 ) . mato grosso ( mt ) : primavera do leste ( 11 ) chapada dos guimarães ( 12 ) rosário oeste ( 13 ) cáceres ( 14 ) . minas gerais ( mg ) : chapada gaúcha ( 15 ) joão pinheiro ( 16 ) . piauí ( pi ) : guadalupe ( 17 ) lagoa alegre ( 18 ) altos ( 19 ) monsenhor gil ( 20 ) amarante ( 21 ) , ribeiro gonçalves ( 22 ) uruçuí ( 23 ) . pará ( pa ) : santa maria das barreiras and redenção ( 24 ) . tocantins ( to ) : gurupi ( 25 ) mateiros ( 26 ) . the localities recorded in the present study are represented by red squares . the type - locality of tupinambis quadrilineatus is shown as an asterisk , the type - locality of its junior - synonym ( tupinambis cerradensis ) is shown as a star and remaining records from the literature are shown as blue circles ( manzani and abe 1997 ; colli et al . 1998 ; guimarães et al . 2007 ; silva jr . et al . 2005 ; vitt et al . 2005 ; mesquita et al . 2006 ; recoder and nogueira 2007 ; ferreira et al . 2009 ; silveira 2009 ; recoder et al . 2011 ; dal vechio et al . 2013 ) . the cerrado savanna biome is highlighted in gray .
distribution . tupinambis cuzcoensis appears to be relatively widespread in the foothills of the andes and the western amazon . in peru it is known from quincemil ( the type locality ) , cuzco at about 750 m and goes to at least 827 m ( fmnh 81378 is from villa carmen , peru ) . in ecuador it occurs in the vicinity of canelos , near the rio bobanasa at about 200 m and , at zancudo , napo , ecuador at about 600 m . it ranges westward into the amazon basin as far as humaita , amazonas , brazil and cuiaba , mato grosso , brazil .
after convincing flor to expand her research into freshwater fishes , she has enjoyed working with me on our byu - stri collaborative project with alda and bermingham on the phylogeny , species delimitation , and phylogeography of the poecilia sphenops species complex ( see above ) ! ! we are also collaborating on comparative phylogeography projects , including a project testing for shared evolutionary responses and predicted patterns of genetic diversity among one species of toad ( rhinella schneideri ) and two species of lizards ( iguana iguana and tupinambis merianae ) codistributed across the “arc of deforestation” ecotone at the interface of the amazon and cerrado biomes .
recently , gols - ripoll et al . [ 42 ] examined the genetic structure of venezuelan tupinambis in different bioregions using nucleotide diversity , haplotype diversity and number of polymorphic sites . they found genetic structuring with all three measures and suggest it is the result of historic biogeographic events , the mérida andes orogeny and the shifts in orinoco river ( which accounted for 71 . 2 % of the molecular variance ) as barriers . they considered the zulia population ( now tupinambis zuliensis ) an evolutionary significant unit . since we have not found evidence of t . teguixin in venezuela , all of their comments likely apply t . cryptus ( and t . zuliensis ) . we did find morphological differences between several of the venezuela t . cryptus populations which supports the genetic structure found by gols - ripoll et al . [ 42 ] . specimens from amazonas tended to be dark , almost melanistic with very little yellow pigmentation , and differed from other t . cryptus populations in having three occipitals contacting the interparietal and a complete fold at the interangular sulcus . the orinoco populations tend to have a dorsal pattern of distinct transverse bands interrupted by longitudinal lines . however , both populations share the other traits typical of t . cryptus .
on the positive side , many of the genera they recognize are monophyletic and are not nested in other genera in our tree , including their ameivula ( cnemidophorus ocellifer ) , aspidoscelis ( unchanged from previous definitions ) , cnemidophorus ( excluding c . ocellifer , c . lacertoides , and c . longicaudus ) , holcosus ( ameiva undulata , a . festiva , and a . quadrilineatus ) , kentropyx ( unchanged from previous definitions ) , salvator ( tupinambis rufescens , t . duseni , and t . merianae ) , and teius ( unchanged from previous definitions ) . we did not sample ameiva edracantha ( their medopheos ) .
. . . nesta sentença , a espécie popularmente conhecida como
tejo
( provavelmente , tupinambis merianae , duméril & bibron , 1839 ) é referida como de hábitos noturnos . entretanto , isto não condiz com a bibliografia científica , uma vez que esta espécie é diurna , realizando suas atividades durante as horas mais quentes do dia ( van sluys ; rocha , 1999 ; vitt , 1995 ; winck ; blanco ; cechin , 2011 ) . quanto aos aspectos comportamentais , também houve registro de equívocos de cunho biológico :
quando o lagarto perde o rabo , ele só tem três dias de vida
. . . .
. . . nesta sentença , a espécie popularmente conhecida como
tejo
( provavelmente , tupinambis merianae , duméril & bibron , 1839 ) é referida como de hábitos noturnos . entretanto , isto não condiz com a bibliografia científica , uma vez que esta espécie é diurna , realizando suas atividades durante as horas mais quentes do dia ( van sluys ; rocha , 1999 ; vitt , 1995 ; winck ; blanco ; cechin , 2011 ) . quanto aos aspectos comportamentais , também houve registro de equívocos de cunho biológico :
quando o lagarto perde o rabo , ele só tem três dias de vida
. . . .
imagine , however , that one of these species , tupinambis teguixin , was in reality a collection of cryptic species some of which are living in sympatry at some locations . by definition , cryptic species are morphologically similar to the human eye , but genetically distinct . such populations have commonly been historically classified as a single species . the phenomena of cryptic species is well known and frequently encountered when detailed studies involving morphology , genetics and ecology are undertaken [ 7 ] . therefore their discovery should not be unexpected , except perhaps for the fact that these lizards are extensively used by humans and have been the subject of hundreds of scientific studies .
size . the largest tupinambis cryptus sp . n . measured was a male 391 mm svl with a 530 mm tail . the smallest was a neonate that was 85 mm svl and a 42 mm tail . fourteen males svl 216–391 mm , x = 281 . 71 mm , sd = 41 . 11 ; seven had undamaged tails 463–635 , x = 448 . 56 mm , sd = 60 . 62 . eleven female svls 183–284 mm , x = 231 . 0 mm , sd = 39 . 73 ; only three had unbroken tails 384–605 , x = 481 . 0 mm , sd = 79 . 87 . smallest individual measured 85 mm svl .
we reviewed the literature and examined illustrations and specimens said to be tupinambis teguixin and t . nigropunctatus in an attempt to understand the characters various authors have attributed to each name . we also consulted researchers with extensive taxonomic knowledge for their opinions on the status of some names . taxonomic decisions are best made on the basis of recognizable morphological characters and concordant molecular evidence [ 33 ] . thus , we reconcile geographic genetic variation with meristic and mensural characters from specimens to produce a robust taxonomic estimate with diagnostic evidence from both molecular and morphological data . this integrates all available data , using the general lineage species concept to delimit evolutionarily distinct clades as independent species [ 34 ] .
large circular markers denote the localities of specimens sampled for dna . smaller circular markers denote localities of specimens identified using morphology : green is clade 1 ( t . cuzcoensis sp . n . ) , blue is clade 2 ( t . teguixin ) , purple is clade 3 , ( t . zuliensis sp . n . ) , and red is clade 4 ( t . cryptus sp . n . ) . the two most northern red circles represent the islands of tobago and trinidad respectively . the other markers denote other species of tupinambis not in the teguixin group . red x = t . palustris . black x = t . longilineus . aqua blue circles = t . quadrilineatus .


attercopus is an extinct genus of arachnids , containing one species attercopus fimbriunguis , known from a devonian-aged fossil .

it is placed in the extinct order uraraneida , spider-like animals able to produce silk , but which lacked true spinnerets and retained a segmented abdomen bearing a flagellum-like tail resembling that of a whip scorpion .

they are thought to be close to the origins of spiders .

an important early devonian ( about 390 million years ago ) fossil example from gilboa , new york , was originally described as a member of the extinct order trigonotarbida and named gelasinotarbus ? fimbriunguis .

it was later assigned to a new genus attercopus and reinterpreted as the oldest , and most primitive , example of a true spider ( araneae ) .

this hypothesis was based on the supposed presence of unique spider features such as silk-producing spinnerets and the opening of a venom gland on the fang of the chelicera .

further study – based on new fossils from a comparable devonian locality called south mountain – and comparison with other material from the permian of russia , i.e. , of permarachne , indicates that attercopus does not actually have spinnerets .

the feature which looked like a tubular spinneret is actually a folded sheet of cuticle .

it would , however , have produced silk from a series of silk gland openings , or spigots , located across plates on the underside of the abdomen .

the opening for the venom gland is also a misinterpretation .

a segmented tail , or flagellum , also belonged to this animal .

it seems unlikely that attercopus spun webs , but it may have used its silk to wrap eggs , lay draglines or construct burrow walls .

attercopus fimbriunguis is not a spider , but it is probably close to the type of animals which did give rise to modern spiders today .

its name is taken from the english dialect word attercop ( " spider " ) , which came from old english attorcoppa ( " poison-head " ) , from ator ( " poison " ) , itself drawn from the proto-germanic * aitra - ( " poisonous ulcer " ) and kopp - ( " head " ) .

attercopus

attercopus was spider - like ,  but was not a true spider .  attercopus had a segmented tail and silk producing organs ,  but probably only used silk for constructing shelters and wrapping eggs ,  rather than constructing elaborate webs .
in the original description of attercopus , several chelicerae were illustrated and described . in at least one of these specimens ( 329 . 22 . ar9 ; fig . 1 f ) , a hole near the tip of the fang was interpreted as a poison gland pore . revisiting this specimen raises uncertainty because other apparent holes on the same fang appear to be artefacts of preservation and none of the chelicera specimens show this pore clearly . mesothele spiders lack poison glands ( 16 ) , and to infer their existence in attercopus would require their loss and reacquisition ( by opithotheles ) in araneae . because the preponderance of the evidence now suggests that poison glands were also absent in attercopus , it is more parsimonious to assume that they were acquired only once , in the spider suborder opisthothelae , and are synapomorphic for that taxon , not for spiders as a whole .
because of the different preservational styles of attercopus and permarachne , it is not clear whether the apomorphies of attercopus ( palpal femur spinules , fimbriate tarsal claws , lack of emargination at distal joint of leg patella ) are shared by permarachne . it is possible that the flagellum was uniquely derived and not homologous with that of the pedipalp orders . although we do not presently have evidence of any synapomorphies for this lineage , we wish to draw attention to its distinctiveness and so establish the ordinal name uraraneida selden & shear ord . nov . ( etymology : greek oura , tail , and latin , aranea , spider ; included taxa : attercopus and permarachne ) . uraraneida and araneae are distinguished from the pedipalp orders by 2 characters : the naked ( seta - less ) cheliceral fang and the presence of opisthosomal silk glands and spigots . the existence of permarachne alongside mesotheles in the fossil record indicates that uraraneida was a persistent lineage that only became extinct ( if , indeed , it is ) some time after the late permian .
silk production from opisthosomal glands is a defining characteristic of spiders ( araneae ) . silk emerges from spigots ( modified setae ) borne on spinnerets ( modified appendages ) . spigots from attercopus fimbriunguis , from middle devonian ( 386 ma ) strata of gilboa , new york , were described in 1989 as evidence for the oldest spider and the first use of silk by animals . slightly younger ( 374 ma ) material from south mountain , new york , conspecific with a . fimbriunguis , includes spigots and other evidence that elucidate the evolution of early araneae and the origin of spider silk . no known attercopus spigots , including the original specimen , occur on true spinnerets but are arranged along the edges of plates . spinnerets originated from biramous appendages of opisthosomal somites 4 and 5 ; although present in limulus , no other arachnids have opisthosomal appendage homologues on these segments . the spigot arrangement in attercopus shows a primitive state before the reexpression of the dormant genetic mechanism that gave rise to spinnerets in later spiders . enigmatic flagellar structures originally described as arachnida incertae sedis , are shown to be attercopus anal flagella , as found in permarachne , also originally described as a spider . an arachnid order , uraraneida , is erected for a plesion , including these two genera , based on this combination of characters . the inability of uraraneida precisely to control silk weaving suggests its original use as a wrapping , lining , or homing material .
the oldest known silk - producing spigots are from the middle devonian of gilboa , new york ( 1 ) . this specimen ( slide 334 . 1b . ar34 , fig . 1 a ) , was described as a nearly complete , fusiform spinneret , consisting of a single article , bearing ≈20 spigots arrayed along the presumed medial surface but more clustered distally . on the basis of the single , simple spigot type and the lack of tartipores ( vestigial spigots from earlier instars ) , the fossil spinneret was compared most closely with posterior median spinnerets of the primitive spider suborder mesothelae . the distinctiveness of the cuticle enabled us to associate the spinneret with remains previously referred tentatively to a trigonotarbid arachnid ( 2 ) . restudy of this material resulted in a fuller description of the animal as the oldest known spider , attercopus fimbriunguis ( 3 ) . the appendicular morphology of attercopus , but little of the body , is now known in great detail . in this article , morphological information on attercopus is described , which significantly alters these earlier interpretations , and provides insights into the evolution of the spider silk system .
specimen sm 1 . 11 . 3b ( fig . 2 b ) shows overlapping layers of undoubted attercopus cuticle with both small setal and large macrosetal follicles but no silk spigots . slightly darker and lighter bands of cuticle are interpreted , as in sm 1 . 11 . 3a , as plate edges and interplate membrane , respectively . the few macrosetal follicles are interpreted as those present at the posterior edges of plates ( and the largest of these occurs adjacent to a darker plate edge ) . the plates taper and become narrower to one side ; the widest plate is torn along most of its width and laterally , whereas the narrower ones are more complete . setae on the specimen point toward the side of the specimen with narrower plates , and ≈3 plates are present . we interpret this specimen as the posterior end of the opisthosoma where the plates narrow . both tergite and sternite remains could be present on this specimen , but the posteriormost , at least , appears to be a complete ring . the importance of this specimen is that emerging from the posterior end are two annular segments with thickened posterior collars that bear a row of ≈12 prominent setal follicles . these are clearly part of the same flagellar organ found in association , but hitherto not in direct organic connection , with attercopus ( 2 ) . despite the virtually identical cuticle pattern , including slit sensilla , between these flagella and attercopus , we described them as arachnida incertae sedis because no flagella are known from spiders . the evidence provided by specimen sm 1 . 11 . 3b shows unequivocally that attercopus did , indeed , bear a postanal flagellum of at least 12 segments . in two of the attercopus specimens ( e . g . , fig . 1 e ) , a distinctive terminal article appears that is 2–3 times as long as the more proximal articles and densely set with setal sockets .
attercopus fimbriunguis , devonian of south mountain , new york , macerated from matrix with hf and slide - mounted . ( a ) part of opisthosoma with rows of spigots , sm 1 . 11 . 3a . ( b ) two flagellar segments emerging from posterior part of opisthosoma , sm 1 . 11 . 3b . ( scale bars : 0 . 5 mm . )
spiders probably evolved about 400 million years ago from thick - waisted arachnid ancestors that were not long emerged from life in water . the first definite spiders , thin - waisted arachnids with abdominal segmentation and silk producing spinnerets , are known from fossils like attercopus fimbriungus . this spider lived 380 million years ago during the devonian period , more than 150 million years before the dinosaurs .
it seems unlikely that the spigot - bearing plates in attercopus are tergites , and much more probable that they represent ventral plates , because in spiders the spinnerets are invariably ventral . if the ventral plates are appendage - derived , the reactivation of genes ( such as distalless ) that would extend these plates once more into segmented appendages would carry along with them the spigots observed in attercopus to be distributed along the posterior margins of those plates . we suggest that developmental genetic studies to determine the homologies of the ventral plates in the pedipalp orders could provide evidence to resolve this question . further evidence that silk spigots are associated with appendages comes from the recent finding that at least one species of mygalomorph spider has silk spigots on its leg tarsi that produce threads that help the spider cling to smooth surfaces ( 10 ) .
the advantage of spigots on spinnerets is that silk production can be controlled to produce complex linear structures , rather than simple , sheet - like masses of threads . our interpretation of spigot location in attercopus suggests that the original use of silk in protospiders was to produce such sheets , perhaps used as burrow linings , to cover egg masses ( 17 ) , or as trails that would allow hunting animals to return to the safety of a retreat ( 18 ) .
name : attercopus . phonetic : at - ter - coe - pus . named by : p .  a .  selden & w .  a .  shear  -  1991 . classification : arthropoda ,  chelicerata ,  arachnida ,  uraraneida . species : a .  fimbriunguis ( type )  . diet : insectivore . size : unavailable . known locations : usa ,  new york .  time period : mid devonian . fossil representation : almost complete .
from our reevaluation of 334 . 1b . ar34 we conclude that the original description is essentially correct , but note that the specimen consists of a sheet of cuticle folded over twice ; thus , the resemblance of the piece of cuticle bearing spigots to a “semifusiform” spinneret ( 3 ) is fortuitous . in summary , the specimens of attercopus bearing spigots are plate - like in morphology , with 2 rows of spigots along the presumed posterior edge . the spigots are not borne on appendage - like spinnerets .
taking the evidence from attercopus and permarachne together , we conclude that both lacked spinnerets but possessed rows of spigots along the margins of sclerotized ventral plates , and a long , multiarticled postanal flagellum . these characters , while evidently plesiomorphic , would exclude attercopus and permarachne from the order araneae as presently defined . removal of permarachne from the mesothelae leaves only one other described mesothele in the fossil record : palaeothele montceauensis from the late carboniferous of france ( 20 ) . a number of other paleozoic fossils have been referred to araneae ; some of these are not spiders at all ( 21 ) , whereas others can be referred to mesothelae with confidence ( p . a . s . , unpublished observations ) . the external mold of the london specimen of palaeothele shows an anal tubercle , and to ascertain whether this continued into a flagellum ( which could place palaeothele as an intermediate between araneae and the order ) , an x - ray computed tomography ( ct ) scan was performed on the specimen by m . d . s . ( fig . 3 d ) . this showed without doubt that there is no flagellum , and therefore palaeothele remains the earliest and only described fossil mesothele spider to date .
a . fimbriunguis specimens were recovered from the rock matrix by digestion in concentrated hydrofluoric acid followed by washing in dilute hydrochloric acid and mounted on plain microscope slides in clearcol mountant . the specimens were studied by using a leica dm2500 m microscope and photographed with a leica dfc420 digital camera attachment . images of the attercopus specimens were captured by using leica firecam software on an apple macbook pro computer and manipulated by using adobe photoshop cs3 software . drawings were made by using a drawing tube attached to the microscope and also by tracing photographic images in adobe illustrator cs3 . all specimens are deposited in the department of invertebrates , american museum of natural history , new york .
many other characters demonstrate that both attercopus and permarachne are spider - like in their morphology , without features of other known pulmonate arachnids ( 3 , 11 ) . among pulmonate orders , only uropygids and schizomids have a postanal flagellum , and only in uropygids is the flagellum long and multisegmented . in other pulmonate orders ( amblypygids , trigonotarbids , and spiders ) , the pygidium is a 1 - to 3 - segmented preanal structure with a postanal tubercle . the multisegmented flagellum may be a plesiomorphy of pantetrapulmonata ( 13 ) that has been retained in uropygi ( where it appears to function as a sensory structure used for aiming shots of the acetic / caprylic acid repugnatorial secretion ) , and in our proposed order where the function is unknown , or it could be a homoplasy .
in permarachne , from the permian of russia , a series of 6 opisthosomal plates are clearly seen ( 11 ) ( fig . 3 a and b ) . in the original description these were interpreted as tergites ( as seen in mesotheles ) even though all other visible structures in the fossil are ventral , a fact originally accounted for by assuming that the specimen represented a molt from which the carapace had been displaced , thus revealing ventral structures in the prosoma . however , these structures are in ventral , not dorsal , view . it now seems more parsimonious to interpret the series of plates as ventral plates , conforming to the ventral view of the rest of the fossil . thus , there is a real probability that , unlike spiders , both attercopus and permarachne bore a series of ventral plates .
a flagellar structure was described in permarachne ( 11 ) , but because such a structure was previously unknown in spiders , yet all other morphological features suggested that permarachne was a mesothele , the structure was interpreted as an elongate , multiarticled spinneret . however , close examination of the specimen shows a complete absence of spigots ; the structure appears to emerge from the posterior of the opisthosoma along the median line ( fig . 3 a and b ) , not laterally as would be expected for a spinneret , and is not matched by any corresponding paired structure on the specimen . spider spinnerets are always paired , except where the anterior median spinnerets are fused into a single cribellar plate or nonfunctional colulus ( 12 ) . in permarachne the flagellum shows setal whorls ( fig . 3 c ) , but only a few segment collars are distinct , because of the poor preservation ; those preserved are similar to the segments of attercopus . extrapolation from the lengths of the more distinct segments , ≈12 articles appear to be present , but the distal end is not preserved .
sm 1 . 11 . 3a ( fig . 2 a ) consists of a subrectangular mass of overlapping layers of cuticle with ≈33 spigots arrayed in an approximate double row along one long edge and an area of unsculptured cuticle along the opposite edge . the folds have their long axes parallel to the shorter edges . these features , together with the setal arrangement , suggest that the preferred orientation is : unsculptured cuticle anterior , spigots posterior , shorter edges lateral . seven macrosetae and / or their sockets are present on sm 1 . 11 . 3a . one posterolateral corner is missing ; spigots are most numerous at the opposite posterolateral corner . because of the presence of spigots , we interpret sm 1 . 11 . 3a as part of the opisthosoma . living and fossil mesotheles have macrosetae at the rear of each large tergite ( 5 ) , and other spiders that lack tergites commonly bear large setae on the opisthosoma that reflect original segmentation ; thus , the macrosetae on attercopus sm 1 . 11 . 3a could also reflect at least 4 sclerotized plates and the transverse lines could represent plate boundaries ( note : both dorsal and ventral surfaces are present ) .
attercopus fimbriunguis , devonian of new york ( localities : g , gilboa ; sm , south mountain ) , macerated from matrix with hf and slide - mounted . ( a ) first - described “spinneret , ” g 334 . 1b . 34 ; darkness of cuticle reflects number of layers , so this fragment is folded over twice . ( b ) palpal femur , sm 1 . 11 . 12 ; arrow indicates patch of distinctive spinules . ( c ) piece of cuticle from corner of opisthosomal ventral plate showing setae , spigots , and possible silk strand , sm 1 . 11 . 4 . ( d ) close - up of e showing possible silk strand emerging from spigot shaft , sm 1 . 11 . 4 . ( e ) flagellar structure with 12 segments ( including possible distalmost ) from original gilboa locality ; segments show distal collars and setae , g 334 . 1a . 4 . ( f ) close - up of cheliceral fang showing a number of holes ( arrowed ) , the most distal of which had been interpreted as a venom - gland opening , g 329 . 22 . 9 . ( scale bars : 0 . 5 mm , except f , 0 . 25 mm . )
sm 1 . 11 . 4 ( fig . 1 c and d ) is a smaller piece of cuticle than sm 1 . 11 . 3a . the distribution of setae and spigots enables orientation of the piece . at one lateral side is an even fold that conforms to the curved outline of the posterolateral margin ; this is interpreted as a doublure along the margin of the plate . it is folded at the lateral side and bears ≈15 spigots in an approximate double row along the posterior edge ; the anterior and opposite lateral edges are torn . if sm 1 . 11 . 4 were once joined to sm 1 . 11 . 3a , then it is likely that it is the missing posterolateral corner of sm 1 . 11 . 3a , with its posterolateral concentration of spigots . of especial interest on sm 1 . 11 . 4 is the long , winding filament emerging from the distal end of one spigot ( fig . 1 e ) . detailed study shows that this is a single strand that is inseparable microscopically from the tip of the spigot , thus leading us to hypothesize that this is a strand of silk . no other silk strands have been seen in attercopus material , but silk from modern spiders is identical in size and appearance under the light microscope .
amptes & attircoppes & suche oþer þat ben euere bisy ben maide to schewe man ensaumple of stodye & labour . [ elucidarium of honorius of autun ( wycliffite version ) c . 1400 ]
it lingered in northern england dialect in the sense
peevish , ill - natured person
( c . 1500 ) .
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further reading -  new terrestrial arachnids from the devonian of gilboa ,  new york .   -  american museum novitates 2901 :  1–74 .   -  william a .  shear ,  paul a .  selden ,  w .  d .  i .  rolfe ,  patricia m .  bonamo & james d .  grierson  -  1987 . -  a spider and other arachnids from the devonian of new york ,  and reinterpretations of devonian araneae .   -  palaeontology 34 :  241–281 .   -  paul a .  selden ,  william a .  shear & patricia m .  bonamo  -  1991 . -  taxonomic names ,  in a spider and other arachnids from the devonian of new york ,  and reinterpretations of devonian araneae .   -  palaeontology 34 : 241 - 281 .   -  p .  a .  selden & w .  a .  shear  -  1991 .
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full reference : w . a . shear , p . a . selden , and w . d . i . rolfe . 1987 . systematic paleontology , in new terrestrial arachnids from the devonian of gilboa , new york ( arachnida , trigonotarbida ) . american museum novitates 2901 : 1 - 74
edited by may r . berenbaum , university of illinois at urbana–champaign , urbana , il , and approved november 14 , 2008 ( received for review september 14 , 2008 )
the defining adaptation of spiders is the production of silk from highly modified appendages called spinnerets , located on the posterior division of the body ( opisthosoma ) . silk emerges from spigots ( modified setae ) arrayed on the spinnerets and connected to internal silk glands capable of producing , in the most advanced spiders , several kinds of chemically and physically distinct fibers . silk is used not only to create webs of various types , but also to produce egg - sac material , for prey wrapping , lining burrows , and to aid in navigation and communication , among other uses . because of the importance of silk and spinnerets in the lives of spiders , clues to the origins of the spinning apparatus are of great importance in understanding the evolution of the group . although silk is important in other animals ( e . g . , moth cocoons ) , no other arthropod group relies so heavily on its use in so many ways . here , we reinterpret old and assess recent fossil evidence , and combine our analysis with developmental genetic studies , to clarify how silk use may have evolved . an unexpected result of the study was the discovery that some paleozoic fossils thought to be spiders represent a hitherto undiagnosed order of arachnida .
collections made in 1993 and 1996 in middle devonian strata [ lower frasnian , lowermost onteora formation , 374 ma ( 4 ) ] at south mountain , schoharie county , new york ( 74°16′30″e / 42°23′55″n ) yielded material that is indistinguishable from a . fimbriunguis from gilboa , and thus presumed to be conspecific . this material includes 3 pairs of chelicerae ( therefore , at least 3 individuals ) , numerous podomeres including a palpal femur showing the distinctive patch of spinules on the inferoanterior surface ( fig . 1 b ) , and two slides with specimens showing spigots . the last are numbered sequentially ( sm 1 . 11 . 3 and sm 1 . 11 . 4 ) , which means they were extracted from the same acid - macerate residue and slide - mounted one after another , and so could be parts of the same animal .
although mesothele spiders and a few mygalomorphs have opisthosomal tergites that can be attributed to the original segmentation of the opisthosoma , no spiders living or fossil have ventral opisthosomal plates . however , these plates are present in all other arachnid orders , including the pedipalpi ( orders amblypygi , uropygi , and schizomida ) , sister group to spiders . there is no evidence for the origin of these plates from genetic studies ; the patterns of expression of hox genes has only been studied in some spiders and mites [ in the latter , with focus on head segmentation , not expression of appendage - determining genes ( 6 ) ] . it has been suggested , on the basis of paleontological and developmental evidence ( 7 ) , that , in scorpions , these plates are not true sternites but are the fused remnants of paired opisthosomal appendages , as indeed seems to be the case for the epigastric plate and book - lung covers of spiders , and the homologous anterior opisthosomal opercula in uropygi ( 8 ) and amblypygi ( 9 ) . in mesotheles the first 2 pairs of book - lung covers are part of continuous sclerotization across the opisthosoma , with distinct posterior margins .
paleozoic araneae and uraraneida . ( a–c ) permarachne novokshonovi , permian of russia , pin 4909 / 12 . ( a ) holotype part in rock matrix . ( b ) explanatory drawing of a . ( c ) close - up of flagellum showing whorls of setae . ch , chelicera ; cx , coxa ; fe , femur ; mt , metatarsus ; pa , patella ; pl , ventral plate ; st , sternum ; ta , tarsus ; ti , tibia . ( d ) palaeothele montceauensis , carboniferous of france , in 62050a , x - ray ct scan showing appendages buried in the rock matrix ; note , anal tubercle ( arrowed ) is not a flagellum . ( scale bars : b , 1 mm ; c and d , 0 . 1 mm . )
spider spinnerets are homologs of biramous opisthosomal appendages , still present in the primitive chelicerate limulus , as demonstrated by expression of the developmental genes pdm / nubbin and apterous in embryos of spiders and limulus ( 14 ) . in limulus these appendages consist of a segmented median branch and a lateral branch with a plate covering lamellate gills . in spider embryos , distalless gene expression shows 4 pairs of spinnerets ( anterior and posterior median and lateral pairs ) represented by 2 pairs of appendage buds on opisthosomal somites 4 and 5 ( 15 ) . the appendage buds each later divide in 2 to produce potentially 4 pairs of spinnerets , although in nearly all spiders some of these buds do not develop into functional postembryonic spinnerets . the full complement of 8 spinnerets is today seen only in the primitive mesotheles liphistius and heptathela ( even in these animals the anterior median pair bears no silk - producing spigots ) ( 16 ) . other homologs of opisthosomal appendages in spiders are the book - lung opercula ( 2 pairs in mesotheles and mygalomorphs , on somites 2 and 3 ) and tracheae derived from appendage apodemes in araneomorph spiders on somite 3 . in other arachnids , homologs of opisthosomal appendages can be seen in the gonopods , book - lung opercula , and ventral sacs of pantetrapulmonates , and other organs in diverse groups ( 13 ) . only spiders show expression of appendage homologs on somites 4 and 5 [ although structures in other orders could be silk gland homologs , such as the fusules in female palpigrades ( 17 ) ] . silk glands also occur in many adult male spiders along the anterior edge of the epigastric furrow ( somite 2 ) . these are termed epiandrous or epigastric glands ( 12 ) , and open through simple spigots ( fusules ) . because of their medial position in relation to the more lateral book - lung opercula , epigastric fusules could be serial homologs of the median spinnerets of somites 4 and 5 .
loss and reappearance of wings in stick insects suggests that genes for appendage development can be suppressed , perhaps by a single disabling mutation , and later reactivated , again perhaps by a reversal of the original mutation or an offsetting mutation that restores gene function ( 19 ) . once these genes were reactivated in the ancestors of spiders , it would be a clear advantage to have the spigots on them as this would confer significantly more control over the use and distribution of silk , as seen in the orb - weaving orbiculariae of today in the construction of their architecturally precise webs .
the holotype and only known specimen of permarachne novokshonovi , pin 4909 / 12 , part and counterpart , comes from the koshelevka formation , kungurian stage , cisuralian series ( permian ) , at the krutaya katushka outcrop , left bank of the barda river , upstream of matveyevka , russia , and is deposited in the palaeontological institute of the russian academy of sciences , moscow . the specimen was studied , under ethanol to enhance contrast , by using a wild m7s stereomicroscope , drawn by using a drawing tube , and photographed with a nikon d1x digital camera attached to the microscope .
a specimen of palaeothele montceauensis , in 62050a housed in the natural history museum , london , was submitted to x - ray ct analyses . these were performed on a phoenix v | tome | x “s” x - ray tomography system in the engineering faculty , imperial college , london . x - ray source energy was 160 kv ; the detector was a 16 - bit flat panel 512 × 512 pixel - direct digital detector using a stepping mode to double initial resolution . analysis and reconstruction of tomographic slices was performed by using the custom spiers software suite ; visualizations are ray - traced isosurfaces of data , manually prepared to remove artefacts and extraneous material .
we thank linda hernick ( new york state museum ) and the new york department of forestry for help in field work at south mountain , and kirill eskov ( paleontological institute , moscow ) for discussions on permarachne .
author contributions : p . a . s . and w . a . s . designed research ; p . a . s . and w . a . s . performed research ; m . d . s . contributed new reagents / analytic tools ; p . a . s . and w . a . s . analyzed data ; and p . a . s . and w . a . s . wrote the paper .
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first report of amber with spider webs and microbial inclusions from the earliest cretaceous ( c . 140 ma ) of hastings , sussex
researchers used field data from 2012 to 2015 to study mortality and allele frequency changes in the sea star pisaster ochraceus during a mass mortality event in northcentral california , and found that surviving adult and juvenile sea stars experienced 81 % mortality and allele shifts , according to the authors .
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a study of cognitive ability in norwegian males born from 1962 to 1991 suggests that environmental factors rather than changing genetic composition of families likely account for most of the change in norwegian population iq .
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spiders were among the earliest animals to live on land , probably evolving about 400 million years ago .
most of the early segmented fossil spiders belonged to the mesothelae , a group of primitive spiders with the spinnerets placed underneath the middle of the abdomen ( rather than at the end as in ' modern ' spiders ) . they were probably ground dwelling predators , living in the giant clubmoss and fern forests of the mid - late palaeozoic , where they were presumably predators of other primitive arthropods ( like cockroaches , giant silverfish , slaters and millipedes ) . silk may have been used simply as a protective covering for the eggs , a lining for a retreat hole , and later perhaps for simple ground sheet web and trapdoor construction .
as plant and insect life diversified so also did the spider ' s use of silk . spiders with spinnerets at the end of the abdomen ( opisthothelae ) appeared more than 250 million years ago , presumably promoting the development of more elaborate sheet and maze webs for prey capture both on ground and foliage , as well as the development of the safety dragline .
by the jurassic period ( 191 - 136 million years ago ) , when dinosaurs roamed the earth , the sophisticated aerial webs of the orb weaving spiders had developed to trap the rapidly diversifying hordes of flying insects . similarly , the diversification of hunting spiders in litter , bark and foliage niches would have progressed in response to new prey - capture and habitat opportunities .
despite this the spider fossil record is relatively poor . during the tertiary period the rich record of amber spider fossils - complete spiders trapped in clear , sticky , tree resins - show us that a spider fauna basically similar to that of the present day existed more than 30 million years ago .
amazingly , segmented mesothelid spiders have survived in eastern asia ( china to indonesia ) from late palaeozoic times to the present day . these large , impressive spiders live in soil burrows with trapdoors in forested areas and caves . segmented spiders are very similar to their ancestors and have virtually remained unchanged . they are not found in australia .
a 300 million year old , half metre long , fossil arachnid , megarachne servinei , was originally described as a spider , but is now thought more likely to represent another type of spider - like ancient arachnid . its unique features include the enormous size , massive shovel - like jaws and ribbed , shield - like covering over the abdomen . an arachnid of this size must have fed on large prey like cockroaches and giant millipedes . but why did this massive predator need such an impressively armoured body - were there even bigger arachnid predators about ?
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