comment on this calibration


 node name
Phasmatodea     Look for this name in NCBI   Wikipedia   Animal Diversity Web
  recommended citations
Wolfe et al. 2016
  node minimum age
98.17 Ma
This fossil is sourced from amber mines in the Hukawng Valley of Kachin State, northern Myanmar (formerly Burma). The depositional age of Burmese amber was estimated from U-Pb dating of zircons from the volcaniclastic matrix surrounding the amber (Shi et al.,2012). Shi et al. (2012) argue the amber is not older than its associated sediments, as burial and preservation would have to be rapid for survival of organic material, so the amber was probably formed at, but not earlier than the U-Pb date: at 98.79 Ma±0.62 Myr. Therefore, a minimum age for any fossil from Burmese amber deposits is 98.17 Ma.
  node maximum age
411 Ma
A soft maximum age is estimated from R. praecursor, the oldest hexapod, from the Early Devonian (Pragian) Rhynie Chert of Aberdeenshire, Scotland. Spore assemblages of the Windyfield and stratigraphically underlying Rhynie Chert are dated to the early but not earliest Pragian to early (earliest?) Emsian (polygonalis-emsiensis Spore Assemblage Biozone) (Parry et al., 2011). Radiometric dating of the underlying Milton of Noth Andesite at ca. 411 Ma (Parry et al., 2011, 2013) has been subject to a dispute over its temporal relationship to hot spring activity associated with the cherts (Mark et al., 2011, 2013) and predates the biostratigraphic dating of the Rhynie Chert relative to the global dating of the base of the Pragian Stage. Therefore, a soft maximum constraint may be defined at 411 Ma for the Rhynie Chert.
 primary fossil used to date this node 
NIGP 163536
Echinosomiscus primoticus, Engel et al. 2016
Location relative to the calibrated node: Crown

[show fossil details]
     Locality: Hukawng Valley
     Geological age: Cretaceous, Mesozoic

More information in Fossilworks   PaleoBioDB

  phylogenetic justification
Until recently, no Mesozoic fossil qualified for membership in the crown group of Phasmatodea (Bradler and Buckley, 2011). E. primoticus bears morphological characters shared with extant members of Euphasmatodea, in particular Heteropterygidae and Aschiphasmatidae, but lack the area apicalis on the tibiae (Engel et al., 2016). It also shares characters with Lonchodinae, such as absent areole on all tibiae, comparatively long antennae, the absence of wings, and the division of the tenth abdominal tergum into moveable hemitergites (Engel et al., 2016). Although a new family was erected to accommodate the unique character combination for E. primoticus, it is very clearly within Euphasmatodea (Phasmatidae s.l.), and thus a member of crown Phasmatodea (Engel et al., 2016).
  phylogenetic reference(s)
Engel,M.S.,Wang, B., Alqarni, A.S., 2016. A thorny, ‘anareolate’ stick-insect (Phasmatidae s.l.) in Upper Cretaceous amber from Myanmar, with remarks on diversification times among Phasmatodea. Cretac. Res. 63, 45–53.
 tree image (click image for full size) 
tree image
Figure 19 from Wolfe et al. (2016).