Roberta Engel

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Doctoral Student

campsite at Mt. Marshall

E-mail: roberta.engel@uconn.edu Voice: (860) 486-6215 Fax: (860) 486-6364
Mailing address:
75 N. Eagleville Road, Unit 3043
Storrs, CT 06269-3043, U.S.A.


Contents

Pseudoscorpions

Pseudoscorpions, also known as Chelonethida or False Scorpions, are an understudied order of arachnids. While not well known, Aristotle made note of pseudoscorpions as did the luminaries Linnaeus and Hooke (Micrographia 1665), and today they star on YouTube. Pseudoscorpions are found throughout the world in a wide range of microhabitats including leaf litter, animal nests, under rocks (even in the intertidal zone), beneath bark, and among the pages of books. One reason many are unfamiliar with pseudoscorpions is their size, most measuring less than 5 mm. This ancient lineage, the fossil record dates to the Middle Devonian (380MYA), currently comprises 25 families, 439 genera, and 3385 species.

Dissertation Research

Mt. Caroline, southwestern Australia

Synsphyronus (Arachnida: Pseudoscorpiones: Garypidae) is a genus of pseudoscorpions found throughout Australia, New Zealand and New Caledonia (Harvey 1987). Currently, there are 24 described species but the diversity is much greater (unpublished data). This group has been collected beneath bark, in leaf litter, and under rocks in mesic and xeric regions. Specifically, I am interested in the origin and diversification of lineages that are endemic to the granite outcrops in southwestern Australia. Only one species, Synsphyronus elegans, has been described from the outcrops, and until recently it was known only from its type locality.
My research objectives include:
• to assess the diversity of Synsphyronus on the granite outcrops of southwestern Australia
• to describe species discovered on the outcrops
• to infer phylogenetic relationships among the rock-restricted lineages in southwestern Australia
• to estimate a species level phylogeny

I have been fortunate to have had three field seasons since starting my dissertation. During my 2004 and 2006 field seasons, I visited over 100 outcrops in southwestern Australia, sampling from the ~70 populations discovered. My sampling suggests that the diversity of Synsphyronus in southwestern Australia is greater than previously recorded. I traveled across Australia to localities recorded for twelve of the 22 Australian species of Synsphyronus during the Australian winter of 2008.

Ultrastructures of the Chelicera

chelicera

Ultrastructures of the chelicera, including the serrula exterior, serrula interior, and flagellum blades, are taxonomically informative characters; I imaged these structures using scanning electron microscopy (SEM). The serrula exterior and interior teeth are heteromorphous. I have discovered papilla-like structures on the tips of the serrula exterior teeth. The serrula exterior is thought to be a grooming organ and the function of these ultrastructures warrants further exploration. Garypids typically have three spinose flagellum blades; the distal-most blade being the longest. The Synsphyronus samples I imaged had three blades (the flagellum shown is abnormal with only two blades). Many of the blades had structures that were more peg-like than spinose.

Pseudoscorpion Molecular Toolkit

Nuclear Genes
I have successfully isolated four nuclear genes (elongation factor 1- subunit α, wingless, actin 5C, and Internal Transcribed Spacer regions 1 and 2) from pseudoscorpions. I have designed new primers and modified published primers.


wingless, (wg)
The wingless primers used, wg1MP_F3 and wg1MP_R3, are modifications of those designed by Brower & DeSalle (1998) for use in beetles (pers. comm. M. Richmond).
wg1MP_F3 5’ GAR TGY AAR TGY CAY GGC ATG TCS GG 3’
wg1MP_R3 5’ ACY ICG CAR CAC CAR TGG AAI GTG CA 3’

Internal Transcribed Spacer regions 1 and 2 (ITS1, ITS2)
The ITS universal primers I used are found in Ji et al. (2003). I modified CAS28sB1 for use in pseudoscorpions.
CAS18sF1 5’ TAC ACA CCG CCC GTC GCT ACT A 3’
CAS28sB1mod 5’ TTT CCT CCG CTT ATT TAT ATG CTT AA 3’


Mitochondrial Genes
I recommend you visit Susan Masta's webpage Arachnid Mitochondrial Primers at http://web.pdx.edu/~smasta/primer_pages/Primer_front.html. Two other sources for mitochondrial primers are the classic paper Evolution, weighting, and phylogenetic utility of mitochondrial gene sequences and a compilation of conserved polymerase chain reaction primers (Simon et al. 1994) and the more recent publication Incorporating molecular evolution into phylogenetic analysis, and a new compilation of conserved polymerase chain reaction primers for animal mitochondrial DNA (Simon et al. 2006).

Pseudoscorpion Projects

Microbisium sp.
Chthonius sp.
I have started to collect, image, and database the local fauna with the help of Evelize Codero (‘09), Elizabeth Riggles ('12) and Ashley Bonet ('12). Evelize imaged specimens collected by Dr. Raymond Pupedis, Senior Collections Manager, Division of Entomology, Yale Peabody Museum of Natural History. Chthonius and Microbisium are two genera found in Connecticut.

The image of Chthonius was featured on UConn's Year of Science 2009 home page in the "What is it?" column .

Science for All

Recommended Reading
NOTE: reading suggestions will continue in September
May 2011: The Diversity of Life E. O. Wilson
April 2011: Reading the Forested Landscape: A Natural History of New England T. Wessels
March 2011: A Sand County Almanac; and sketches here and there A. Leopold
February 2011: The Immortal LIfe of Henrietta Lacks R. Skloot
January 2011: The Botany of Desire M. Pollan
December 2010: Why Evolution Is True J. Coyne

Children's Literature
As an evolutionary biologist and a former elementary school teacher, I am interested in the literature that is available to school age children. I have started a collection of books and a goal for the fall is to review a book each month. Titles I have collected include,

Jackson, Ellen The Tree of Life, The Wonders of Evolution
Lasky, Kathryn One Beetle Too Many, The Extraordinary Adventures of Charles Darwin
Markle, Sandra Animals Charles Darwin Saw, An Around-the-World Adventure
Manning & Granstrom What Mr. Darwin Saw
Peters, Lisa W. Our Family Tree, An Evolution Story
Schanzer, Rosalyn What Darwin Saw, The Journey that Changed the World
Sis, Peter The Tree of Life


Pay your books forward. Consider donating books to groups such as Books Through Bars [www.booksthroughbars.org/]. I have accumulated several used biology textbooks and found a local group that will put them to use!

Instructor

Field Entomology

Teaching Assistantships

Entomology Teaching Collection Assistant
General Entomology
Medical Entomology
Evolutionary Biology
General Ecology
Principles of Biology I & II (majors)
Foundations of Biology (non-majors)

Connecticut Entomological Society

http://www.insectsingers.com/ces/ces.html

2009-2010 President
2008-2009 Vice President
2007-2008 Vice President
2009-2010 Speaker Series
May: K. Zyko (CTDEP), L. Saucier (CTDEP), M. Thomas (CAES) & C. Maier (CAES); The Natural Diversity Database (DEP) and Status Update on Connecticut State-listed Insects
April: Kathy Hill & David Marshall, UConn; A Cicada Travelogue
March: Jan Conn, Wadsworth Center; Recent divergence or deep population structure? Complexities of the primary neotropical malaria vector Anopheles darlingi (Diptera: Culicidae)
February:Jadranka Rota, Smithsonian Institution; Systematics and defensive behaviors of metalmark moths (Lepidoptera: Choreutidae)
January: Kentwood Wells, Dept. Chair, EEB, UConn; Beetles, Bees, and Butterflies: Charles Darwin and the Study of Insects
November: Patrick Getty, UConn; Fossil Trackways of Modern Basal Insects
October: Andrew Stoehr, Yale; Variation in Melanism in Pierid Butterflies
September: Kirby Stafford III, CAES; Asian Longhorned Beetle: A Threat to our Trees

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