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University of Nebraska - Lincoln DigitalCommons@University of Nebraska - Lincoln Faculty Publications from the Harold W. Manter Laboratory of Parasitology Parasitology, Harold W. Manter Laboratory of 4-1997 A Guideline for the Preparation of Species Descriptions in the Eimeriidae Donald Duszynski University of New Mexico, [email protected] Patricia G. Wilber University of New Mexico Follow this and additional works at: https://digitalcommons.unl.edu/parasitologyfacpubs Part of the Parasitology Commons Duszynski, Donald and Wilber, Patricia G., "A Guideline for the Preparation of Species Descriptions in the Eimeriidae" (1997). Faculty Publications from the Harold W. Manter Laboratory of Parasitology. 156. https://digitalcommons.unl.edu/parasitologyfacpubs/156 This Article is brought to you for free and open access by the Parasitology, Harold W. Manter Laboratory of at DigitalCommons@University of Nebraska - Lincoln. It has been accepted for inclusion in Faculty Publications from the Harold W. Manter Laboratory of Parasitology by an authorized administrator of DigitalCommons@University of Nebraska - Lincoln. A Guideline for the Preparation of Species Descriptions in the Eimeriidae Author(s): Donald W. Duszynski and Patricia G. Wilber Source: The Journal of Parasitology, Vol. 83, No. 2 (Apr., 1997), pp. 333-336 Published by: The American Society of Parasitologists Stable URL: http://www.jstor.org/stable/3284470 Accessed: 20/04/2010 00:03 Your use of the JSTOR archive indicates your acceptance of JSTOR's Terms and Conditions of Use, available at http://www.jstor.org/page/info/about/policies/terms.jsp. JSTOR's Terms and Conditions of Use provides, in part, that unless you have obtained prior permission, you may not download an entire issue of a journal or multiple copies of articles, and you may use content in the JSTOR archive only for your personal, non-commercial use. Please contact the publisher regarding any further use of this work. Publisher contact information may be obtained at http://www.jstor.org/action/showPublisher?publisherCode=asp. Each copy of any part of a JSTOR transmission must contain the same copyright notice that appears on the screen or printed page of such transmission. JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact [email protected]. The American Society of Parasitologists is collaborating with JSTOR to digitize, preserve and extend access to The Journal of Parasitology. http://www.jstor.org J. Parasitol., 83(2), 1997 p. 333-336 ? American Society of Parasitologists 1997 CRITICALCOMMENT... A GUIDELINEFOR THE PREPARATIONOF SPECIES DESCRIPTIONSIN THE EIMERIIDAE Donald W. Duszynski and Patricia G. Wilber Departmentof Biology,The Universityof New Mexico,Albuquerque, New Mexico87131 ABSTRACT: Membersof the suborderEimeriina (phylum Apicomplexa: class Sporozoea:order Eucoccidiorida) have complex 1 or 2 host life cycles thatinvolve endogenousdevelopment in the tissues of vertebratesor invertebratesand exogenous development in an oocyst, usually outside the host(s). Because tissue stages are logistically difficult or even impossible to obtain in natural (wild) host-parasitesystems, the vast majority(>98%) of species in this parasitecomplex are known only from the structureof their sporulatedoocyst. Unfortunately,the qualityof these species descriptionsis uneven because no guidelinesare availablefor workersin the field to follow. Here we proposea specific set of guidelinesfor the preparationof species descriptionsof coccidia based predominentlyon the structureof the sporulatedoocyst, because the oocyst is the most readily availablestage in the life cycle. In addition,we emphasizethat ancillarydata be incorporatedwhenever possible with the species description;these data may include,but are not limitedto, ecological parameters,prevalence, seasonal data, and the depositionof both host symbiotypes and parasitehepantotypes (=phototypes) into accreditedmuseums so thataccurate identification of both host and parasitematerial can be assured in perpetuity.And finally, if oocysts are collected in pure suspension, that is, if only one coccidian species (morphotype)is presentin the sample,then some oocysts should be saved in 70% ethanoland archivedin an accreditedmuseum in the event that futureworkers might wish to amplify and, later,sequence the parasite'sDNA. Ultimately, the value and robustness of any classification by published descriptions of poor quality and emphasized that scheme, from the species to all higher taxonomic categories, such practice, "ridicules taxonomic research in this group in rests on the foundation of the species description. Within the the eyes of other parasitologists." The same also can be said protozoan phylum Apicomplexa Levine, 1970, about one-third for the taxonomy of species within the Eimeriidae. of the approximately 5,000 described species reside in a single Therefore, our objectives in this paper are to emphasize and family, Eimeriidae, and about 98% of these species are known encourage greater precision in the description of new coccidian only from 1 life-cycle stage, the sporulated oocyst, which has species when only the sporulated oocyst is available, and es- a limited number of structural characters. Unfortunately, the tablish certain minimal guidelines for proper description of fewer the number of morphological characteristics in a group these oocysts in the hope these guidelines will be followed both of parasites, the more bothersome the species problem becomes, by those describing and naming new coccidians and by the and within the Eimeriidae it is not possible to delimit what is editors of the journals who consider these papers for publica- a species to everyone's satisfaction. Thus, if the taxonomy of tion. this group is to be useful for higher level examination (system- atic, phylogenetic, zoogeographic, host specificity, and other SAVING, STORING, AND PREPARING studies), the taxonomic followed in the procedure documenting OOCYSTS FOR OBSERVATION existence of new eimeriid species must not only be consistent, but it should follow the intent, if not the letter, of the Interna- Before oocysts can be studied critically, they must be prop- tional Code of Zoological Nomenclature. As Ernst Mayr (1957) erly maintained to keep them viable so that their structural in- clearly pointed out, "It is unrewarding to pursue the problem tegrity remains intact. In our experience, oocysts from different of host specificity" (or other biological problems) "unless one's vertebrate host species fall into two groups, which, of necessity, conclusions are based on sound systematics and reliable host need to be handled differently when collected under field con- records." ditions. After working on the taxonomy of coccidia over the past 2 decades, it has become painfully clear that procedures used by Oocysts from birds, mammals, and terrestrial those who describe new species, in the past and up to the pres- invertebrates and reptiles ent, are not consistent in many ways with the International Code. For the Code recommends the des- example, explicitly These oocysts keep best when fresh feces are placed directly of for new but a tradition ignation type specimens species, type into 2-2.5% aqueous (w/v) potassium dichromate (K2Cr207) in had been lacking among taxonomists working with the Eimer- a ratio of 1 volume of feces: >5 volumes K2Cr207. In field iidae until Bandoni and Duszynski (1988) a frame- provided collections, either snap-cap or screw-cap 16-25-ml vials work work to help resolve this problem. Lom and Arthur (1989) rec- well, but one should not fill the vial all the way to the top; ognized a similar deficiency in the way myxosporean species leave a layer of air between the top of the feces-dichromate were described and they published, "A guideline for the prep- mixture and the cap to allow the oocysts some atmospheric aration of species descriptions in Myxosporea." In their paper, oxygen. Unfortunately, other solutions for feces, for example, they pointed out the many difficulties created for later workers 2% (v/v) aqueous sulfuric acid (see Wash et al., 1985) or com- mon laboratory fixatives for oocysts (see Duszynski and Gard- Received 15 July 1996; revised 21 October 1996; accepted21 Oc- ner, 1991), have proven unsatisfactory either for keeping oo- tober 1996. cysts viable or for preserving them as types. 333 334 THEJOURNAL OF PARASITOLOGY,VOL. 83, NO. 2, APRIL1997 Oocysts from amphibians, fish, and aquatic invertebrates GUIDELINES FOR DESCRIPTIONS AND and reptiles SPECIES DIFFERENTIATION These oocysts often are very thin walled and fragile and some- We strongly suggest that the following criteria be presented times prove difficult to sporulate. When examining hosts from to allow accurate evaluation of a proposed new species descrip- freshwater environments, fresh mucus and feces from the intes- tion for coccidians (family Eimeriidae). In the list of features tinal tract should be placed in vials with tap water or with filtered below, we have followed the example of Lorn and Arthur river water at room temperature. Likewise, mucus and gut con- (1989) by marking those features that are indispensable with a tents of marine animals should be placed in containers with fil- solid circle (*), while those recommended for inclusion