Lazarus effect and Lazarus taxa

The discovery of a new naraoiid nektaspid in the Upper Silurian (Pridolian) of southeastern Ontario significantly extends the range of this unusual group. Nektaspids are nonmineralized arthropods typical of Early and Middle Cambrian soft-bottom communities, but were thought to have become extinct in the Late Ordovician. The unique holotype specimen of Naraoia bertiensis n. sp. comes from a Konservat–Lagerstätte deposit renowned for its eurypterid fauna (the Williamsville Member of the Bertie Formation). Naraoia bertiensis lacks thoracic segments and is morphologically similar to Naraoia compacta from the Middle Cambrian Burgess Shale, save for the presence of a long ventral cephalic doublure and a subtly pointed posterior shield. To examine the phylogenetic relationships of the new naraoiid, we coded characters of the holotype specimen and of nine previously described nektaspids. The results confirm a sister taxon relationship between Naraoia compacta and Naraoia bertiensis and the monophyly of nektaspid forms lacking thoracic segments (family Naraoiidae). This latter group may have arisen from an ancestral segment-bearing form through heterochronic loss of thoracic segments early in the Cambrian. The disjunct occurrence of a naraoiid nektaspid in the Late Silurian resembles the reappearance of other “Lazarus taxa” that were thought to have been eliminated during mass extinction events. The naraoiid lineage survived the Late Ordovician biotic crisis, but in this case the “Lazarus effect” seems likely to be taphonomic in origin.

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Prompt Recanalizaton of Basilar Artery (Lazarus Effect) in Patient with Acute Ischemic Cardioembolic Stroke in Spite of Relatively Late Start of Fibrinolytic Therapy

Journal of Vascular Medicine & Surgery ◽

10.4172/2329-6925.1000179 ◽

2015 ◽

Vol 03 (01) ◽

Author(s):

Yarovinsky N Eran A

Keyword(s):

Basilar Artery ◽

Fibrinolytic Therapy ◽

Cardioembolic Stroke ◽

Late Start ◽

Lazarus Effect

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The Lazarus Effect: Rejuvenation of Leaf-senescent Seedlings in a Rare Grassland Perennial

The American Midland Naturalist ◽

10.1674/0003-0031(1999)141[0212:tlerol]2.0.co;2 ◽

1999 ◽

Vol 141 (1) ◽

pp. 212-214 ◽

Cited By ~ 2

Author(s):

PETER D. VICKERY ◽

ANDREA M. SULZER ◽

SHARON KELLY

Keyword(s):

Lazarus Effect

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Laonastes and the "Lazarus Effect" in Recent Mammals

Science ◽

10.1126/science.1124187 ◽

2006 ◽

Vol 311 (5766) ◽

pp. 1456-1458 ◽

Cited By ~ 63

Author(s):

M. R. Dawson

Keyword(s):

Lazarus Effect

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Presence of iguanid lizards in the European Oligocene Lazarus taxa and fossil abundance

BSGF - Earth Sciences Bulletin ◽

10.2113/gssgfbull.183.6.653 ◽

2012 ◽

Vol 183 (6) ◽

pp. 653-660 ◽

Cited By ~ 5

Author(s):

Marc Augé ◽

Daniel Pouit

Keyword(s):

Late Oligocene ◽

Lazarus Effect

Abstract During the Eocene, iguanid lizards were a diverse and widespread group in Europe. Prior to this study, no iguanid was known in Europe after the Eocene-Oligocene boundary. Some specimens from the locality of Pech-du-Fraysse (late Oligocene, MP28, France, Phosphorites du Quercy) are described. They belong to the Iguanidae, more precisely to the genus Geiseltaliellus, demonstrating that iguanid lizards survived the Eocene-Oligocene extinctions in Europe, only to disappear in the aftermath, certainly during the latest Oligocene. Thus, Geiseltaliellus is recognized as a Lazarus taxa. Explanations pertaining to the Lazarus effect are examined.

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