DOI: 10.15468/kqtg2w
title: A Revision of the Genus Diastolinus Mulsant and Rey (Coleoptera: Tenebrionidae)

description: This dataset contains the digitized treatments in Plazi based on the original journal article Hart, Charles J., Ivie, Michael A. (2016): A Revision of the Genus Diastolinus Mulsant and Rey (Coleoptera: Tenebrionidae). The Coleopterists Bulletin 70 (3): 485-540, DOI: 10.1649/0010-065X-70.3.485, URL: http://dx.doi.org/10.1649/0010-065x-70.3.485ABSTRACTThe West Indian genus Diastolinus Mulsant and Rey, 1859 (type species: Blaps clathratus Fabricius) is revised. The genus now includes 18 species divided among three species-groups, eight of which are described as new species herein: Diastolinus chalumeaui Hart and Ivie, new species (Guadeloupe Archipelago); Diastolinus leewardensis Hart and Ivie, new species (Leeward Islands); Diastolinus shieli Hart and Ivie, new species (Redonda); Diastolinus azuaensis Hart and Ivie, new species (Hispaniola); Diastolinus desecheo Hart and Ivie, new species (Desecheo Island); Diastolinus doyeni Hart and Ivie, new species (Puerto Rico); Diastolinus vaderi Hart and Ivie, new species (Hispaniola); and Diastolinus hoppae Hart and Ivie, new species (St. Lucia). The following new synonymies are proposed: Diastolinus hummelincki Marcuzzi, 1962 = Diastolinus clavatus Mulsant and Rey, 1859, new synonymy; Diastolinus mulsanti Marcuzzi and D’ Aguilar, 1971 = Diastolinus clavatus Mulsant and Rey, 1859, new synonymy; and Diastolinus estebani Garrido, 2004 = Diastolinus coarctatus (Mulsant and Rey, 1859), new synonymy. A lectotype and paralectotypes are designated for Diastolinus hummelincki Marcuzzi, 1962 (not Marcuzzi, 1949 nor 1950), Blaps clathrata Fabricius, 1792, Ctesicles insularis Champion, 1896, and Ctesicles maritimus Champion, 1896. All species are keyed, illustrated, and redescribed, and extensive corrections of misidentifications are reviewed. All 18 species are readily distinguished by both morphological and biogeographical attributes. Newly revised distributions demonstrate that most species distributions can be closely tied to Pleistocene eustastic minima.Key Words: West Indies, Caribbean, taxonomy, darkling beetles, xerophiles, Pleistocene eustastic minimaDiastolinus Mulsant and Rey are small to moderate-sized (∼ 4.8–10.6 mm) blapstinoid beetles distributed in the eastern Greater Antilles (Hispaniola, Puerto Rico, and the Virgin Islands), and the Lesser Antilles. Ivie and Hart (2016) defined the West Indian blapstinoid group as members of the Opatrina sensu Iwan (2001) with a laterally divided eye, the division being made up of the epistomal canthus extending front-to-back so that the eye is divided into upper and lower lobes (e.g., Figs. 25, 52, 57), and having the male foretarsus expanded (e.g., Figs. 25, 51, 63). Among the blapstinoids, Diastolinus is characterized by diverse body forms sharing the flightless syndrome discussed by Ivie and Hart (2016; see also Hopp and Ivie 2009), i.e., rounded humeral angles (e.g., Figs. 4, 8, 12), short metasternum (Fig. 57), absent or reduced flight wings; intercoxal process of ventrite 1 broad and truncate anteriorly (e.g., Figs. 5, 9, 13, 28); fused elytra; ventrite 1 with a series of strong punctures at the anterior margin, immediately behind the metacoxa (e.g., Figs. 5, 9, 13, 28); and, most diagnostically, the elytron with a particular modification of the striae so that the anterior end of stria 8 is displaced laterad and cut off from base of elytra by stria 7, which also curves laterad and ends either at the humeral angle or the lateral stria (Figs. 2, 27, 88; Ivie and Hart 2016, fig. 52).On islands, there may be strong selective pressures to become flightless (Darlington 1943; Hopp and Ivie 2009). We hypothesize that Diastolinus represents a clade of blapstinoids that had a common winged ancestor similar to a modern Blapstinus Dejean. This wingless condition seems to have freed the epipleuron and humeral structures to be radically different in form, possibly explaining the diversity of forms and shapes exhibited in Diastolinus.As redefined by Ivie and Hart (2016), Diastolinus includes 13 currently recognized species, of which three are synonymized herein and another eight newly described. This flightless group is common in xerophytic habitats within its range (Hispaniola to Grenada), although details of its biology are unknown. Diastolinus now includes the genera Sellio Mulsant and Rey and Ctesicles Champion, but excludes many former Diastolinus that Ivie and Hart (2016) removed to Xerolinus Ivie and Hart, Blapstinus, Goajiria Ivie and Hart, and Nevisia Marcuzzi.Ivie and Hart (2016) review the broader taxonomic history of the West Indian blapstinoids and the resulting redefinition of Diastolinus used herein. For purposes of zoological nomenclature, that paper has priority over this, under the principle of First Revisor. The taxonomic history of this redefined genus began in 1792 when Fabricius named the earliest recorded Diastolinus species, Blaps clathratus Fabricius, from St. Croix. The type species of Sellio was named a little over ten years later with the Swedish worker Quensel describing Blaps tibidens Quensel from Puerto Rico (Quensel in Schönherr 1806). In that same volume, Schönherr (1806) first used the name “ Opat. perforatum ” as a nomen nudum attributed to Gyllenhal, placed in synonymy with Fabricius’ (1792) valid name Blaps punctata (B. punctatus is now the type species of Blapstinus). Two years later, Sahlberg (1823) made the name available when he first applied a description to the name Opatrum perforatum. For a full discussion of the availability of this name and its authorship, see the Discussion under Diastolinus perforatum (Schönherr, 1806).It was not until 1859 that Diastolinus and Sellio were separated from Blaps and Opatrum and described in Mulsant and Rey’ s (1859) revisionary work. That work yielded the new combinations Diastolinus clathratus (Fabricius), Diastolinus perforatus (Schönherr), and Sellio tibidens (Quensel), as well as two new species: Diastolinus clavatus Mulsant and Rey and Sellio coarctatus Mulsant and Rey.The genus Ctesicles Champion, 1896 was originally said to be distantly allied to Diastolinus, but no direct comparison was made between the two genera (Champion 1896). In that paper, Champion named two species: Ctesicles insularis and Ctesicles maritimus.Diastolinus as now defined was largely untouched besides species lists (Leng and Mutchler 1914; Gebien 1938; Blackwelder 1945) for more than 50 years until Marcuzzi began working on the group in the late 1940s. His initial works on the group were mostly focused on the South American fauna (Marcuzzi 1949, 1950, 1954, 1959), now placed in Goajiria. It was not until 1962 that he described any new West Indian species of true Diastolinus – Diastolinus hummelincki Marcuzzi, 1962. Unfortunately, he apparently forgot that he had already named a completely different species Diastolinus hummelincki Marcuzzi, 1949 (now in Goajiria) from South America. He replaced his own primary homonym in 1971 with the name Diastolinus mulsanti Marcuzzi, 1971. A few years later, he described Diastolinus elongatus Marcuzzi, 1977 from Puerto Rico. However, this was also a self-made primary homonym of Diastolinus elongatus Marcuzzi, 1976 from Cuba (now in Xerolinus). Diastolinus elongatus Marcuzzi, 1977 (not 1976) from Puerto Rico was replaced by Garrido (2002) with the new replacement name Diastolinus victori Garrido, 2002 for the Puerto Rican species. In addition to naming species, Marcuzzi (1984, 1998, 2001, 2002) added many new island records to the point that it seemed most species were widespread and sympatic.The next author that named West Indian Diastolinus was Garrido (2004a, b, 2007), who described Diastolinus estebani Garrido, 2004 and Sellio gladiator Garrido, 2004 from Hispaniola. The most recently named species was Diastolinus espoloni Garrido, 2007 from Hispaniola.In spite of a long taxonomic history, the group has not been given a proper revisionary treatment since Mulsant and Rey (1859). As a result, species definitions are difficult to interpret, relationships between species are not well understood, and mistakes in the recorded distributions are rampant. Ivie and Hart (2016) give a long and detailed discussion of the resulting confusion.