1✉ Retired, currently, 22, route de la Côte, CH-1615 Bossonnens, Switzerland & Musée royal de l’Afrique centrale, B-3080 Tervuren, Belgium & Université Catholique de Louvain, B-1348 Louvain-la-Neuve, Belgium.
2021 - Volume: 61 Issue: 4 pages: 1023-1035https://doi.org/10.24349/6yc5-1lxw
To Prof. G. W. Krantz
Naming as an ontological process is an old practice known in Western and Middle East cultures (cf. the introduction of the Enûma Eliš, the Babylonian epic composed roughly in the 18th to 16th centuries BCE) and in early Chinese perspective (cf. the beginning of the Tao Te Ching dating back two millennia). Naming species is not supposed any longer to be an ontological process for modern biologists and naming conventions are now regulated by codes (the International Code of Zoological Nomenclature (ICZN) for animals).
Names of mites are recorded in impressive catalogs published, in the past or recently, on paper (e.g. Araújo et al. 2020; Barros et al. 2020; Bolland et al. 1998; Camicas et al. 1998; Fan et al. 2016; Lin & Zhang, 2002; Moraes et al. 2004, 2016; Mesa et al. 2009; Castilho et al. 2012, 2016; Prasad, 2013; Niedbała and Liu, 2018). Some groups are treated such as the Tydeidae (Silva et al. 2016) but others, as the Ereynetidae, are neglected.
Recently, online databases are becoming a standard tool to study taxonomy. The Tree of Life Web project (ToL) was launched around 1995. However, ToL is limited to large assemblage of mites (family or superfamily as Tydeoidea) and the site has not been updated since 2011. Other online databases on mite species are currently in use as those published by Migeon et al. (2011, 2021) for Tetranychidae, by Castro et al. (2020, 2021) for Tenuipalpidae, by Demite et al. (2014, 2021) for Phytoseiidae, by Santos et al. (2018, 2021a, b, c) for Ascidae, Blattisociidae and Melicharidae.
Another online project is proposed by Wikispecies, a project supported by the Wikimedia Foundation. Its aim is to create a comprehensive free content catalogue of all species; the project is directed at scientists, rather than at the general public (Anonym, 2005). Currently, it contains more than 750.000 articles.
The new database is part of this project and concerns the Tydeoidea as defined by André & Fain (2000), a taxon recognized by Walter et al. (2009: 244–245) and Zhang (2011: 130). The superfamily consists of 4 families, the Ereynetidae, the Iolinidae, the Triophtydeidae and the Tydeidae. On 21 November 2021, the database consisted of 1 324 records or pages related to the Tydeoidea. The distribution was 724 records for the Tydeidae, 334 for the Ereynetidae, 203 for the Iolinidae and 63 for the Triophtydeidae. It ran from Calotydeus croceus (L., 1758) sensu Oudemans (1928) to the Lorryia described by Bizarro et al. (2020).
The database began on paper when the author was a student under Prof. G.W. Krantz. An electronic database ensued and was based on two layers, the names (the signifier of linguists, the ''symbol'' or ''name'' of Remsen, 2016) and the ''real'' species and its biology (the signified of linguists, the ''referent'' of Remsen, 2016). Only the first part was transferred into a public database, name by name. Inputs are essentially based on personal data and bibliographical references (books, articles, reviews and previous catalogs) on Tydeoidea taxonomy. The transfer began in November 2015.
The database may be consulted at the following address: https://species.wikimedia.org/wiki/Tydeoidea and is open access. This article (electronic version) provides direct links to the database for tydeoid taxa.
Describing Wikispecies philosophy is beyond the scope of this paper. Briefly, Wikispecies involves several user groups with different access rights. The author is an autopatroller (currently, 298 persons enjoy this status). The right to create or edit records is granted to experienced users who have demonstrated an understanding of Wikispecies policies and guidelines. This means that such a user can be trusted not to submit inappropriate material, deliberately or otherwise, and that the user submits new material often enough that it is more efficient to mark it all as approved preemptively.
In agreement with ICZN, Tydeoidea https://species.wikimedia.org/wiki/Tydeoidea is usually attributed to Kramer (1877) who advanced the term ''Tydidae'' for this taxon. The very term ''Tydeoidea'' was, however, first used in print by Cunliffe (1955) who is responsible for designating and naming this taxon that encompasses the Tydeidae. The superfamily was proposed to accommodate the families Tydeidae https://species.wikimedia.org/wiki/Tydeidae , Speleognathidae https://species.wikimedia.org/wiki/Speleognathidae , Ereynetidae https://species.wikimedia.org/wiki/Ereynetidae , and Paratydeidae https://species.wikimedia.org/wiki/Paratydeidae (figure 1).
The modern concept of Tydeidae as detailed by André & Fain (2000) is quite different of the Tydeidae treated by Thor (1933) or by Baker (1965). In contrast, the modern concept of Ereynetidae was already fixed by Fain (1957), except the Pseudotydeinae erected later by Baker & Delfinado (1974) and synonymized to Ereynetinae by André & Fain (2000: 437).
The family Speleognathidae erected by Womersley (1936) was lowered in the hierarchy and included in the Ereynetidae by Fain (1957: 251). Similarly, the superfamily Iolinoidea erected by Pritchard (1956) was lowered in the hierarchy and included in the Tydeoidea by Krantz (1978: 237). In contrast, some families, such as the Paratydeidae and the Nematalycidae, were temporarily integrated into the Tydeoidea but are currently excluded from the superfamily.
A page or record concerns a taxon and is divided into sections (Figure 2). At the top, the taxonavigation section presents the systematic hierarchy. It is followed by the name section, the notes and the references. At the bottom are found the external links and various categories. An image free from copyright may illustrate the taxon.
The taxonavigation section begins with names that link to taxa located immediately up and down in the hierarchy (families, subfamilies, tribes, genera, subgenera, species and subspecies) and helps users to move up and down in the hierarchy.
Each taxon dealt with on the page is marked in bold, has one parent taxon and an unlimited number of child taxa which are listed. The nec subsection lists names of child taxa that are not recommended. Such lists result from synonymies (Homeotydeus is a junior synonym of Calotydeus), homonymies (Tydides), and new combinations (Boydaia angelae is the original combination of Lawrencarus angelae).
All names recorded in the literature have been included, even the misspelling and ''old'' names. For instance, the Microereunetidae, the replacement name proposed by Botazzi (1950), is reported under the record ''Ereneytidae''. Australotydeinae, another misspelling for Australotydaeinae used by André (1979: 199, 200) and Silva et al. (2016: 6), is included. Similarly, the idiosyncratic misspelling used by Vandel (1965), Spelaeognathopsis instead of Speleognathopsis, is cited. Another idiosyncratic misspelling concerns the genus Speleomys: the genus Spelaeomys erected by Hooijer (1957) for a giant prehistoric rat is misspelled Speleomys by Geer et al. (2010: plate 21), hence a false homonymy, i.e. a homonymy resulting from a misspelling.
Otherwise, the correct and current name is given in full, e. g. Boydaia cyanerpes hylocichla Fain & Hyland, 1975 or Trispeleognathus striatus (Crossley, 1952), the combination used by Skoracki et al. (2018: 420) after 5 subsequent combinations.
Fossil species are also included, for instance Palaeotydeus devonicus, even if they are not assigned to a specific subfamily.
The name of each taxon is followed by the author(s). Encoded authors are in blue. Clicking on an author name in blue will display the authority page. Then click on ''Taxon names authored'' to see a list of taxa he described.
It is thus possible to track the activity of acarologists: Baker (129 tydeoid taxa), Kaźmierski (88 taxa), Kuznetsov (78 taxa), André (60 taxa), Momen (49 taxa) and Ueckermann (43 taxa). Alex Fain deserves special mention in describing 154 taxa. Figure 3 illustrates the number of species he described by decade and his influence on ereynetid taxonomy.
The second part of a specific name is the species epithet, its ending must agree in gender with the name of the genus. This requirement is much debated among taxonomists of various taxa, for instance by lepidepterologists (Sommerer, 2002; Nieukerken et al. 2019).
For mites, the French oribatologist Grandjean (1936: 36) already listed arguments against such an obligation. He was probably the first acarologist to adopt the principle of original orthography. Nowadays, the rule of ICZN is not helpful when applying modern electronic tools in taxonomy and systematic zoology. An entry in a database should remain unmodified as long as possible so that easy retrieval and exchange with other systems are safeguarded. Recent publications do not respect the rule such as the world catalog of Silva et al. (2016). Others do the reverse as in the paper review of Kaźmierski (1998a, Tydeus reticulatus but Lorryia reticulata) or the electronic database on Tetranychidae (Monoceronychus californicus, the original combination, followed by Tetranychina californica, Migeon et al. 2021).
The new database follows the gender agreement. The gender of genera is thus provided and some names are even corrected. For example, Lorryia crucifera, the original combination used by Karg (1973), is named Brachytydeus cruciferus and not Brachytydeus crucifera, the subsequent combination used by Silva et al. (2016: 9) and corrected under art. 34.2 of ICZN.
The type locality with the habitat is briefly detailed. Possibly, there is a link to the host: for instance, Boydaia pheucticola is linked to the host of the holotype, Pheucticus melanocephalus, a bird assigned to the Cardinalidae.
Follow the abbreviation of the repository, for example KMMA or MRAC for the Royal Museum for Central Africa to get the full data of the institution housing the name-bearing type. The stadium of the name-bearing type is also indicated.
The chaetotaxy of many species was not given in old original descriptions. In the absence of modern redescription, these ''ancient'' species, as called by Kaźmierski (1998), are considered species inquirendae.
For instance, if the user selects ''Tydeus foliorum'', he gets, in the name section, a question mark symbol followed by the message ''Species inquirenda. The status, affinity, scope or nomenclature of this taxon is unclear. Please see discussion on the talk page.'' The user is thus invited to consult, complete or create the corresponding talk page. This concerns about 68 tydeid species (14% of Tydeidae, among which 50 species inquirendae assigned to ''Tydeus'') and 16 ereynetid species (6% of Ereynetidae).
Nomina nuda are not rare in Tydeoidea. Phoenicopteriella womersleyi was formally described by Fain (1956: 33–36) after a first citation by Fain (1955: 696). The latter use is thus a nomen nudum and the description date is 1956. Similarly, there are 13 other cases of ''preliminary descriptions'' or undue citations.
Another exemple is offered by the species described by Dugès (1834) and named caudatus. The name Tydeus caudatus does not conform to the rules of the International Code of Zoological Nomenclature and does not mean anything, it is a nomen nudum (André 2011). The user gets, in the name section, a hazard symbol followed by the message ''The name of this taxon appears to be invalid under the relevant nomenclatural code. It is a nomen nudum''. Two other nomina nuda used in Tydeidae result from mispellings.
Some taxa give raise to different interpretations. This was the case for the genus Tydeus where two nomenclatural systems coexisted (André & Kaźmierski, 2006) until the decision by ICZN (2008). Nowadays, this is the case for the genera Lorryia and Brachytydeus. If these genera are consulted, the user gets a question mark symbol followed by the message ''The status, affinity, scope or nomenclature of this taxon is unclear. Please see the discussion below or comments on the talk page''. The user is thus invited to read the discussion ending the notes section or to consult, complete or create the corresponding talk page. The same message is displayed for the genus Afrotydeus and its type species, Tydeus munsteri.
Up to 10 synonyms are displayed for the genus Tydeus. Where both types of synonyms coexist in the subsection, the distinction between objective and subjective synonyms is made.
Each of two or more synonyms that denote nominal taxa with the same name-bearing type, or (in the cases of family-group and genus-group taxa) that denote nominal taxa with name-bearing types whose own names are themselves objectively synonymous (ICZN, 1999).
A nice example is the subfamily Pseudotydeinae that was erected to receive a genus'somewhat atypical of the Tydeidae' and assigned to the Tydeidae (Baker & Delfinado, 1974). The subfamily was transferred to Ereynetidae and synonymized with Ereynetinae by André & Fain (2000: 437).
Another example is given by a species dedicated to Womersley: Speleognathus womersleyi, the original combination, has been followed by 5 different genus/subgenus/species combinations, Speleognathus (Trispeleognathus) womersleyi, Trispeleognathus womersleyi, Trispeleognathus (Trispeleognathus) womersleyi, Ophthalmognathus womersleyi and Phoenicopteriella womersleyi.
A secondary synonym is produced in Paratydaeolus clavatus, the species described by Momen & Lundqvist (1996) after Paratydaeolus was considered a junior synonym of Coccalicus, the genus erected by Willmann (André & Uusitalo, 2006). The subsequent combination, Coccalicus clavatus, gives rise to a preoccupied name and is replaced by Coccalicus clavamomen (nomen novum).
The successive combinations involving Brachytydeus, Lorryia or Tydeus appears in 81 tydein species (17% of Tydeinae).
Each of two or more names whose synonymy is only a matter of individual opinion, i.e. it is not objective (ICZN, 1999) and does not relate to nominal taxa with the same name-bearing type. For instance, if the user selects ''Pseudotydeinae'', he gets, in the name section, a hazard symbol followed by the message ''The name of this taxon appears to be invalid under the relevant nomenclatural code, as it is a redundant synonym of Ereynetinae''. The name of the senior synonym is a link to the appropriate record, to Ereynetinae in this example.
There are however exceptions to this basic approach. According to Koch (1838), his Tetranychus viburni is ''humeris inermibus'' (there is no ''Schulterborsten'', no setae on shoulders) as indicated in his drawing reproduced in Figure 4. The difference from Tetranychus urticae is emphasized by Koch (1842: 59-60) who placed T. urticae in a species-group with ''Drei lange Schulterborsten'' (easy to see even with a dissecting microscope, Fig. 4A) and T. viburni in another group with ''Schulterborsten entweder fehlend oder ungemein kurz''. The former character concerns only the second and last species of the group, T. salicis, and does not involve T. viburni. Koch's statement and his division in 2 groups are repeated by Oudemans (1937: 1017). The absence of setae on shoulders is also noticed by Thor (1933: 31). However sketchy the leg chaetotaxy drawn by Koch is, it also differs between urticae and viburni. ''Die Beine ziemlich kurzborstig'' (''The legs are rather short-bristle'') noticed Koch (1838) in his description of T. viburni. Consequently, the synonymy advanced by Pritchard & Baker (1955: 437) who did not refer to Koch's publication is not followed in the database. Tetranychus viburni is resurrected from synonymy and considered a tydeid species as proposed by Thor (1933: 31)
Another exception is provided by Coboydaia crassipes described in the genus Ereynetes by Berlese & Trouessart (1889). According to Domrow (1969: 386), the species nigra described by Fain (1956b) is a junior synonym of crassipes. Although Domrow's synonymy is reported, Skoracki et al. (2018: 430) used the combination Coboydaia nigra, a combination also used in the database and Coboydaia crassipes is treated as a separate species, at least temporarily.
Homonymy results from the principle that, in zoology, the name of each taxon must be unique. Consequently a name that is a junior homonym of another name must not be used as a valid name. Primary homonyms are those with the same genus and same species in their original combination. Genera or other monolectic term (one-word term) are homonyms only if exactly the same — a one-letter difference is enough to distinguish them. Secondary homonyms can be produced if taxa with the same specific name but different original genus are later classified in the same genus (Art. 57.3, 59). True homonyms with replacement names are listed in Table 1.
The genus Oriola was unnecessarily given the replacement name Oriolella by Baker (1969) on the false assumption that Oriola was preoccupied by the name of the golden oriole (Aves). The name was revalidated by André (2004) but the replacement name was previously used, e.g. by Kaźmierski (1998b: 36). The same remark applies to Microereunetidae, a replacement name proposed by Botazzi (1950) for the family Ereneytidae.
Homonymy is associated with disambiguation pages listing pages that would otherwise share the same title (plants and animals included). Indeed, the genus name Meyerella may refer to green algae, sponges or mites.
Notes consider historical aspects of the past studies. For instance, the genus Ereynetes erected by Berlese in 1883 was divided in four subgenera by Fain (1964: 104) and, subsequently, in five subgenera in the same publication (Fain, 1964: addenda 110; 1985: 257–258).
Notes relate peculiar difficulties too. For instance, the systematics of Proctotydaeus (nominal subgenus) is made uncertain due to the presence of two male forms, homeomorphic and heteromorphic males (Kaźmierski 1998a: 43). Similarly, species identification of Coboydaia crassipes is made difficult according to Fain (1957: 253-254).
The notes also report presence or absence in lists published in previous catalogs (e.g. Silva et al. 2016) or reviews (e.g. André, 1985; Kaźmierski, 1998b).
Lastly, hypotheses and deliberation on the use of scientific names are advanced in the discussion subsection. Tydeus viburni might be the old name of Tydeus goetzi since both mites are frequent on Viburnum (see figure 4). Koch (1838) even noticed, at the posterior end of the idiosoma, the presence of ''very short, capillary setae, mostly pasted with debris'' (''Am Hinterrande sehr kurze, feine, meistens mit Unrath beklebte Borstchen'').
Another hypothesis concerns the real identification of Tydeus caudatus auctorum. Tydeus goetzi was first identified as T. caudatus by Akyazi et al. (2017) and might replace the nomen nudum at least in some cases.
The reference section details the works cited in the main text.
Anywhere in the record, a hyperlink in blue points to an author (e.g. Berlese), to another taxon, or to the host. Links to external sites are provided in the link section (for the Ereynetidae, there are links to the distribution in Africa, ION and Nomenclator Zoologicus).
A record ends up with various categories (specialized layout), such as the author(s) of taxa, disputed taxa, the repository.
On every page there is a search box entitled ''Search Wikispecies'' (Figure 2). Enter key words and phrases and press Enter or Return on your keyboard. Or click the magnifying glass icon, Search, or Go button. If a page has the same title as what you entered you will be directed to that page. Otherwise, it searches all pages on the database, and presents a list of articles that matched your search terms, or a message informing you that no page has all the key words and phrase.
Acarologists have compiled catalogs, handbooks, or checklists that attempt to sort out the classification and nomenclature of mites, but such works are invariably outdated soon after publication. New species are discovered and other revisions are made. On the contrary, an electronic database as that described above may be completed with missing data, corrected, amended and updated with newly described species.
Nowadays, electronic mite databases refer to host plants, distribution and current classification after an initial search procedure. Only Spider Mites Web gives an overview of successive nomenclatural acts under the heading ''Nomenclature''.
The new database intends to be exhaustive and comprehensive as far as all tydeoid taxa are covered, ''ancient'' as well as fossil species. It is focused on the current nomenclature and all nomenclatural acts associated with a taxon (be it a superfamily, family, subfamily, tribe, genus, subgenus, species or subspecies). This way, it is possible to figure out the history of the taxon. Another advantage of this electronic database is the hyperlink (text in blue) that allows the users to directly jump to an author, to another taxon or to the host even if it is not a mite. Furthermore, all pages are completed by a search procedure available anytime.
Lastly, the new database pertains to the public domain and is open access. Data can be consulted by anyone, and anyone, contrarily to other online databases, can edit nearly any page and improve it immediately. Discussions are even possible for disputed taxa via the talk pages. However, created files and edits by IP-addresses and users who have not yet been given autopatrolled user rights, will to be patrolled and checked that they follow Wikispecies rules and standard.
As summarized by Godfray et al. (2009: 949), the wiki model has both strengths and weaknesses. The strengths are its democratic and open nature and the harnessing of many scientists. This corresponds to the consensus taxonomy described by Scoble et al. (2007). Next, Wikispecies tends to be a knowledge base with a structured taxonomy: if a genus is moved to another subfamily, all the component species are automatically transferred to the new subfamily even if their name is unchanged. Another advantage of Wikispecies is its perenniality as opposed to personal database (this was the case of ScaleNet, a database on Coccoidea initially launched in 1995 and relaunched in a larger structure by García Morales et al. (2016)). Its weaknesses are its susceptibility to sabotage, and the lack of quality and authoritativeness of some of its entries. Wikispecies would have failed to attract many experts to provide entries, perhaps because of the lack of any editorial moderation. Contrary to other mites, the last failure does not apply to the Tydeoidea, at least as the database currently stands.
This article is dedicated to Prof. G.W. Krantz who introduced the author to practical aspects of acarology. The database or preliminary drafts of this publication were read and criticized by D.A. Crossley Jr., C.H.W. Flechtmann, R. Jocqué, A. Migeon, J. Travé and anonymous referees. The translation of Koch's description is partly from Jörg Spelda. Last but not least, the author wishes to thank his two spouses, Marie-France and Marise, for their successive ''bed and breakfast''.