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Department of Invertebrate Zoology

The Department of Invertebrate Zoology is dedicated to the study of invertebrate animals (exclusive of insects) and enhancing the scientific value of the National Collection to understand the natural environment. Among the NMNH biology departments, Invertebrate Zoology spans the greatest phyletic diversity and all major habitats, from the equator to the poles and from the depths of the oceans to the peaks of the tallest mountains.


The Department of Invertebrate Zoology supports original research on all major invertebrate animal groups except insects. Research efforts focus on systematics, phylogeny, morphology, life histories, biogeography, ecology, and genes to genomics. Though the department has a strong marine focus, it also hosts research programs on terrestrial and freshwater mollusks and worms, with important conservation elements. IZ recently became the new home for the US National Parasite Collection (comprised primarily of animal parasites). Department scientists continue to discover and document the wealth of unknown invertebrate diversity. In addition, they increasingly are focused on the nexus of species delimitation and population genetics. Research programs often are collections-oriented and include field components, which can be in terrestrial, freshwater and marine environments, including caves. Marine sites near Smithsonian laboratories on the coasts of Florida, Belize, as well as Caribbean and Pacific Panama have been studied especially extensively. Currently there is a strong focus on southwestern Pacific and Indo-Pacific sites such as French Polynesia, Indonesia and Philippines, among others. Marine specimens are obtained by hand, SCUBA, ship-based trawls, dredges and plankton nets, as well as deep submersibles and underwater remotely operated vehicles. A plot of IZ specimen collection sites outlines all coasts and covers much of the globe. Current department scientists study invertebrates throughout the world, driven by distribution and knowledge gaps for their particular interests.


The approximately 60 million specimens of the U.S. National Invertebrate Collection are organized into collections primarily by traditional phyla, but also as plankton, meiofauna and animal parasites. Included are representatives from all currently recognized invertebrate phyla. The collections are housed on over 18 miles of shelving, in 16,500 drawers with a combined storage area of 2.3 acres, and 70 steel tanks. They include about 70,000 lots of types – specimens of the same species collected at the same time and place – or about 335,000 individual type specimens. Each year approximately 100,000 specimens are loaned to students and researchers around the world and about 15,000 new specimens are added to the collection. About 75% of the specimens in the collection are fluid-stored (alcohol) and 25% dry. The alcohol collections of the Department of Invertebrate Zoology are located in an offsite collection storage facility in the Museum Support Center, Maryland, about 10 miles from downtown Washington, D.C. The facility offers state-of-the-art environmental controls, life safety systems, storage for collections, and labs for Museum and visiting scientists.

Incorporated into the general reference collections are significant holdings originating from federally-funded programmatic studies, including more than 92,000 lots from the US Department of Commerce fishery surveys (NOAA/NMFS and its precursors); more than 192,000 lots from the US Department of the Interior from site surveys for oil and gas leases (BOEM, MMS and USGS), which include more than 76,000 lots of invertebrate collected from the Gulf of Mexico. Also included are more than 40,000 lots of polar invertebrates the majority collected in conjunction with NSF’s US Antarctic Program (USAP). The collections also feature specimens collected from surveys of hydrothermal vents. Collections for Crustacea, Mollusks and Parasites are our largest but most of the department’s other collections rate, among their counterparts, as the most important or among the few most important in the world.


The Crustacean collection is the world’s largest, with more than 600,000 lots and about 25,250 lots of types. Of the approximately 5,200 known genera of Crustacea, 4,800, or 91%, are represented in the collection. The crayfish collection is one of the most extensive in the world.


The mollusk collection holds more than 900,000 lots and over 13,800 types. Special strengths include gastropods and bivalves of North America; Indo-Pacific marine fauna; world-wide Cephalopoda; and Antarctic Ocean fauna. Spring snails in the US and Mexican deserts have been studied extensively to track current and past water-courses.


The United States National Parasite Collection (USNPC) was established in 1892 and acquired by IZ in 2013. It is a cornerstone of global and North American parasitology and one of the most active parasite collections in the world, and had been maintained by scientists and curators of the Agricultural Research Service of the United States Department of Agriculture for the past 70 years. The USNPC holdings include more than 100,000 catalogued lots of animal parasites, focusing on helminthes and to a lesser extent other groups; included are approximately 3,000 holotypes and 7,000 type series.

Other Invertebrates

The collections include over 100,000 lots of Cnidaria including 3,680 types; 70,000 lots of Porifera/Protozoa with 7,312 types; and 30,000 lots of Tunicates, with 305 types. Approximately 98% of the known echinoderm families are represented in the collections. The worm collection totals over 92,000 lots and 9,350 lots of types. Collections for annelids (especially oligochaetes, leeches, branchiobdellids, polychaetes, sipunculans, and vestimentiferans), nematodes and nemerteans are considered world class in size as well as in taxonomic and geographic coverage.


The Department of Invertebrate Zoology has a histology laboratory for traditional anatomical preparations as well as preparing specimens for scanning electron microscopy (SEM). In addition to warming trays and rotary microtomes, an automatic tissue processor and embedding center are available for use. Standard compound and dissecting microscopes are available for examining prepared specimens. Specialized equipment includes two ultramicrotomes for thin sectioning.

Field Work

Field studies are underway throughout the US and the world, especially at marine sites but also in many terrestrial sites.

Education and Outreach

The Department of Invertebrate Zoology participates in several cooperative graduate education programs including formal affiliations with George Washington University; University of Maryland, College Park; American University; George Mason University; University of Louisiana, Lafayette; and the Rosenstiel School of Marine and Atmospheric Sciences at the University of Miami. Department staff serve on graduate committees for a variety of Universities in the United States and throughout the world.


The invertebrate zoology library currently holds over 5,000 volumes and maintains 27 journal subscriptions, focusing on systematics and taxonomy; morphology, anatomy and physiology; ecology and distribution; genetics and evolution; and paleobiology of invertebrates. The Department also houses a superb collection of invertebrate reprints on mollusks, polychaete worms, leeches, oligochaetes, crustaceans, nematodes, and nemerteans. The Wilson Copepod Library contains all known literature for copepods and branchiurans, and a comprehensive database with over 49,000 bibliographic entries (available online at: The Rathbun Library (Crustacea) has approximately 2,100 items, including 6 journal subscriptions. The Mollusks collection incorporates the gift of the William Healy Dall Library and contains about 7,000 volumes and 56 journal subscriptions on recent and fossil malacology, including Bivalvia, Gastropoda and Cephalopoda. There are also comprehensive specialty libraries covering the Echinodermata, Cnidaria, Porifera and Annelida.

Research Staff

CAIRNS, Stephen D., Research Zoologist and Curator of Cnidaria. B.A. (1971) University of New Orleans; M.S. (1973), Ph.D. (1976) University of Miami. Research specialties: Systematics, zoogeography, mineralogy, and phylogeny of Neogene to Recent Scleractinia, Octocorallia and Stylasteridae worldwide.

HERSHLER, Robert, Research Zoologist, Curator of Mollusks. B.A. (1975) State University of New York, Stony Brook; M.A. (1980), Ph.D. (1983) Johns Hopkins University. Research specialties: Systematics, phylogenetics, and biogeography of freshwater mollusks.

LEMAITRE, Rafael, Research Zoologist and Curator of Crustacea. B.A. (1977) Universidad J. Tadeo Lozano; M.S. (1981) Florida International University; Ph.D. (1986) University of Miami. Research specialties: Systematics, biology, and zoogeography of decapod crustaceans, especially hermit crabs, worldwide.

MEYER, Christopher, Research Zoologist and Curator of Mollusks. B.A. (1988) Colgate University; M.A. (1992) University of California, Berkeley; Ph.D. (1998) University of California, Berkeley. Research specialties: Marine speciation, diversification, biogeography and phylogeography history, assembly and maintenance of tropical reef communities; DNA barcoding; phylogeny and systematics of Cypraeidae, Conus, and other diverse, reef-associated gastropod groups.

NORENBURG, Jon, Chair of Invertebrate Zoology, Research Zoologist and Curator of Nemertea. B.A. (1973), M.S. (1976) Acadia University; Ph.D. (1983) Northeastern University. Research specialties: Morphological and molecular phylogeny, phylogeography, biogeography and functional anatomy of nemertean worms, worldwide; biology and zoogeography of soft-bodied marine interstitial fauna, worldwide.

OSBORN, Karen, Research Zoologist and Curator of Annelids and Peracarids. B.S. Zoology (1996) Andrews University, M.S. (1999) Western Washington University, Ph.D. (2007) University of California Berkeley. Research speciality: Evolutionary biology of deep, pelagic invertebrates, specifically Polychaeta and Peracarida.

PHILLIPS, Anna J., Research Zoologist and Curator of Clitellata and Cestoda. B.S. (2006) Appalachian State University, Ph.D. (2011) The City University of New York. Research specialties: Biodiversity, phylogenetic relationships, and evolutionary history of parasitic worms, with emphasis on leeches and tapeworms.

RUETZLER, Klaus, Research Biologist and Curator of Porifera. Matura (1955) Realgymnasium, Vienna; Ph.D. (1963) University of Vienna. Research specialties: Systematics and biology of sponges; marine ecology, especially of Caribbean coral reefs and mangroves.

STRONG, Ellen, Research Zoologist and Curator of Mollusks. B.A. (1991) University of California, Berkeley; Ph.D. (2000) George Washington University. Research specialties: Phylogeny and systematics of the Caenogastropoda based on morphological and molecular data; evolution of feeding biology in the Mollusca (Caenogastropoda; Bivalvia).

Affiliated Research Staff

COLLINS, Allen Gilbert, Adjunct Scientist, Systematics Laboratory, National Marine Fisheries Service, Department of Commerce. B.A. (1987) Amherst College; Ph.D. (1999) University of California, Berkeley. Research specialties: Evolutionary history and systematics of cnidarians and sponges.

HARASEWYCH, M.G., Research Zoologist Emeritus. B.A. (1972) Drexel University; M.S. (1978), Ph.D. (1982) University of Delaware. Research specialties: Systematics, molecular evolution, biogeography and population genetics of gastropod mollusks, worldwide; Deep-sea Mollusca; Cerion, Pleurotomariidae, Neogastropoda.

NIZINSKI, Martha, Adjunct Scientist and Curator of Lobsters, Systematics Laboratory, National Marine Fisheries Service, Department of Commerce. B.S. (1983) West Virginia Wesleyan College; M.S. (1986) University of Maryland; Ph.D. (1998) College of William and Mary. Research specialties: Taxonomy, systematics and biodiversity of decapod crustaceans, especially squat lobsters; biodiversity and community ecology of the invertebrate faunal assemblage associated with deepwater coral habitats.

PAWSON, David L., Senior Scientist Emeritus. B.A. (1960), M.S. (1961), Ph.D. (1964) Victoria University. Research specialties: Systematics and ecology of echinoderms, especially sea cucumbers and sea urchins, worldwide; reproductive biology; hybridization.

ROPER, Clyde, Research Zoologist Emeritus. B.A. (1959) Transylvania University, Lexington, KY; M.S (1962), Ph.D. (1966) Institute of Marine Sciences, University of Miami, Florida. Research specialties: Systematics and biology of cephalopods; giant squid, bioluminescence, deep sea squids.

VECCHIONE, Michael, Adjunct Scientist, Curator of Cephalopod and Pteropod Mollusks, and Systematics Zoologist and Director, National Marine Fisheries Service Systematics Laboratory. B.S. (1972) University of Miami; Ph.D. (1979) College of William and Mary. Research specialties: Systematics, development, biogeography, and ecology of cephalopods.