You are here » home advanced search Xenosaurus fractus


Can you confirm these amateur observations of Xenosaurus fractus?

Add your own observation of
Xenosaurus fractus »

We have no photos, try to find some by Google images search: Google images

Higher TaxaXenosauridae, Diploglossa, Anguimorpha, Sauria, Squamata (lizards)
Common Names 
DistributionMexico (N Puebla)

Type locality: Puebla, Municipality of Huehuetla, approximately 0.7 km N Chilocoyo del Carmen, 20.0862°N, 97.6530°W, 980 m elevation.  
TypesHolotype MZFC 32179, (Figs 1–2). An adult male (field number EPR 1375); collected by Edmundo Pérez Ramos, Itzel Durán Fuentes, and Walter Schmidt Ballardo on 8 June 2003.Paratypes (Fig. 4). Nine; all from Puebla: six topotypes (MZFC 32180–85); one from the Municipality of Huehuetla, Chilocoyo del Carmen, 20.0802°N, 97.6549°W, 880 m (MZFC 9579); one from the Municipality of Huehuetla, “Huehuetla,” 20.1108°N, 97.6529°W, 950 m (approximately 2.8 km W Huehuetla) (MZFC 32187); and one from the Municipality of Xochitlán, “ribera del rio Apulco, near Zacapoaxtla” (approximately 5.6 km SSE Xochitlán), 19.9225°N, 97.6046°W, 1470 m (MZFC 32186). 
DiagnosisDiagnosis: Xenosaurus fractus may be distinguished from all of the other species of Xenosaurus, except X. tzacualtipantecus, by lacking a continuous dark crossband on the nape, or collar; and having instead a funnel-shaped mark on the nape formed by the dorsal color pattern of the head extending posteriorly, gradually narrowing on the nape (while bordered by the posterior extension of a narrow, dark brown stripe on the canthus temporalis, the posterior extension of a broad, cream sub-ocular stripe, and a broad, black stripe on each side), to the frst brown crossband on the trunk (posterior extensions of the subocular stripes remaining narrowly separated medially at their posterior end), versus a mainly uninterrupted dark crossband on the nape enclosed anteriorly by the pale subocular stripes, which extend medially onto the nape producing a pale crossband (often interrupted medially) similar to those on the trunk, and a pale crossband in the scapular region separating the dark crossband on the nape from the frst dark crossband on the trunk in the other species.Xenosaurus fractus may be distinguished from X. tzacualtipantecus by having, on av-erage, more subdigital scales on the fourth toe (26–34, x = 29.9, n = 10; versus 23–28, x = 25.6, n = 8, in X. tzacualtipantecus) and dorsal surface of the limbs barred (black-edged, cream bars on mid upper arm, forearm, thigh, and shank; versus limbs usually not barred in X. tzacualtipantecus [upper arm, forearm, thigh, and shank specked with black; specks usually not forming a distinct pattern; coalescing into narrow lines, bor-dering ill-defned bars and showing a tendency to anastomose, on thigh and shank in one specimen; n = 8]). 
CommentHabitat: rocky outcrop between coffee plantations and cloud forest patches; rock crevices. 
EtymologyTe specifc epithet is an adjective in the nominative case (masculine, singular declension) derived from the Latin verb frangō (“to break”), meaning “broken” or “fragmented.” The name is in reference to the broken dark crossband on the nape in this species. A continuous dark crossband on the nape, or collar, is present in most species of Xenosaurus, and represented in the new species only by black stripes on the sides of the nape, widely separated by posterior extensions of the dark lines on the canthi temporales and the cream subocular stripes. 
  • Kwet, Axel 2018. Neue Höckerechse aus Mexiko. Terraria-Elaphe 2018 (6): 63 - get paper here
  • Nieto-Montes de Oca A, Sánchez-Vega H, Durán-Fuentes I 2018. A new species of knob-scaled lizard (Xenosauridae, Xenosaurus) from the Sierra Madre Oriental of Puebla, Mexico. ZooKeys 737: 141-160 - get paper here
  • Woolrich-Pina, G. A., Smith, G. R., Lemos-Espinal, J. A., Marquez-Guerra, S., Alvarado-Hernandez, A. and Garcia-Montiel, J. C. 2020. Ecology of Xenosaurus fractus (Squamata: Xenosauridae) from Sierra Nororiental, Puebla, Mexico. Current Herpetology 39: 1-12. - get paper here
External links  
Is it interesting? Share with others:

Please submit feedback about this entry to the curator