go to the Tree of Life home page
Under Construction
This is an archived version of a Tree of Life page. For up-to-date information, please refer to the current version of this page.


Stylianos Chatzimanolis and James S. Ashe
taxon links [down<--]Xanthopygina Interpreting the tree
close box

This tree diagram shows the relationships between several groups of organisms.

The root of the current tree connects the organisms featured in this tree to their containing group and the rest of the Tree of Life. The basal branching point in the tree represents the ancestor of the other groups in the tree. This ancestor diversified over time into several descendent subgroups, which are represented as internal nodes and terminal taxa to the right.

example of a tree diagram

You can click on the root to travel down the Tree of Life all the way to the root of all Life, and you can click on the names of descendent subgroups to travel up the Tree of Life all the way to individual species.

For more information on ToL tree formatting, please see Interpreting the Tree or Classification. To learn more about phylogenetic trees, please visit our Phylogenetic Biology pages.

close box
phylogeny from Ashe and Chatzimanolis (2003).
Containing group: Xanthopygina


Sharp (1876) described the first known species of Elmas, E. modesta from Nicaragua, in his new genus Selma Sharp. Later, Bernhauer (1915) described E. strigella from Brazil, also in Selma. Blackwelder (1952) recognized that Selma Sharp 1876 was a junior homonym of Selma Adams 1863, and he proposed the replacement name Elmas Blackwelder 1952. The remainder of the known species of Elmas was described by Ashe and Chatzimanolis (2003). Species of Elmas are Neotropical; they are distributed from Nicaragua to Bolivia, from 20 to 700 meters in wet tropical lowland forests (most specimens from 200 meters or below), except in Bolivia where they have been collected in Yungas forests at 1000 and 1450 meters.


These large black staphylinids are among the most distinctive among the subtribe Xanthopygina. Species of Elmas are medium to large, 11-23 mm in total length, with body uniformly black; body luster in most dull due to very fine and dense punctuation, though a few species have the integument shining between more distant punctures. They may be recognized by the combination of:

 image info  image info  image info  image info

From left to right, left mandible dorsal aspect, right mandible dorsal aspect, labium and maxilla of E. hanleyi.

 image info

Labrum of E. hanleyi.

Discussion of Phylogenetic Relationships

The phylogeny above is the strict consensus tree. The lineages of Elmas species are only weakly resolved by the available dataset (Ashe and Chatzimanolis 2003). Few well-supported conclusions can be drawn. Elmas is strongly supported to be a monophyletic lineage, and E. strigella is probably the most basal known species. Elmas spinosus + E. falini + E. gigas are strongly supported to be a monophyletic group; among known species they are unique in having a strong spine medially on the submentum and a longitudinally depressed area between the antennae. Elmas hibbsi is more weakly supported to be the sister group to these three species. The E. windsoriE. patillas lineage, consisting of 2 Panamanian and 2 Costa Rican species, is found in all trees, but is not strongly supported. It is interesting that within this lineage, the Panamanian and Costa Rican species are sister species in all reconstructions (E. windsori + E. costaricensis and E. panamaensis + E. patillas).


Ashe, J. S. and S. Chatzimanolis. 2003. A revision of the genus Elmas Blackwelder, 1952 (Coleoptera: Staphylinidae: Staphylininae: Xanthopygina), with a preliminary reconstructed phylogeny of the species. Scientific Papers of the Natural History Museum of the University of Kansas. 28: 1-41.

Bernhauer, M. 1915. Zur Staphyliniden-Fauna von Südamerika Zeitung 76: 291-301.

Blackwelder, R. E. 1952. The Generic names of the beetle family Staphylinidae. United States National Museum Bulletin 200: 1-483.

Sharp, D. 1876. Description of a new genus and some new species of Staphylinidae from Mexico and Central America. Transactions of the Entomological Society of London. 1876: 425-432.

Title Illustrations
Scientific Name Elmas hanleyi
Location Costa Rica
Size 14 mm
Copyright © 1997 James S. Ashe
Scientific Name Elmas gigas
Location Peru
Size 23 mm
Copyright © 1997 James S. Ashe
About This Page

Development of this page made possible by National Science Foundation PEET grants DEB 95-21755 and DEB 99-78110 to James S. Ashe.

All images on this page copyright © 2003 James S. Ashe.

Stylianos Chatzimanolis

Santa Barbara Museum of Natural History, 2559 Puesta del Sol Rd, Santa Barbara, CA, 93105, U.S.A.

James S. Ashe

Division of Entomology, Natural History Museum, University of Kansas, Lawrence, KS 66054, U.S.A.

Citing this page:

Chatzimanolis, Stylianos and Ashe, James S. 2003. Elmas. Version 01 January 2003 (under construction). http://tolweb.org/Elmas/10267/2003.01.01 in The Tree of Life Web Project, http://tolweb.org/

close box

This page is a Tree of Life Branch Page.

Each ToL branch page provides a synopsis of the characteristics of a group of organisms representing a branch of the Tree of Life. The major distinction between a branch and a leaf of the Tree of Life is that each branch can be further subdivided into descendent branches, that is, subgroups representing distinct genetic lineages.

For a more detailed explanation of the different ToL page types, have a look at the Structure of the Tree of Life page.

close box


Page Content



Explore Other Groups

random page