A description of the male, including illustrations of the male genitalia, and a colour image of the habitus of the extremely rare species Ctenophilothis altus (Lewis, 1885) are provided for the first time. Further support for the monophyly of the genus Ctenophilothis Kryzhanovskij, 1987 is given.

Coleoptera , Histeridae , Saprininae , Ctenophilothis

In 2013 I published a revision of the genus Ctenophilothis Kryzhanovskij, 1987 (Lackner 2013). At the time of that revision this genus consisted of only two psammophilous Saharan species, both very rare. Although C. chobauti (Théry, 1900) has been found several times in the Moroccan and Algerian Sahara (Olexa 1990, Gomy et al. 2014), the other species, C. altus (Lewis, 1885) was known only from the female holotype and another female, collected in upper Egypt (Lackner 2013). During my recent visit to the Zoological Museum of the Humboldt University Berlin, Germany (ZMHUB) I discovered in the collection a male of this species, collected in Asyut, central Egypt.

In this short correspondence I publish the discovery of the third specimen of the extremely rare C. altus, together with the color image and illustration of its hitherto unknown male genitalia. Both Egyptian localities of this species are likewise mapped herein. As already noted by Lackner (2013) the genus Ctenophilothis is most probably monophyletic, sharing e.g. the absence of the antennal cavity, shortened or strongly reduced lateral costa of the antennal groove or the peculiar shape of protibia (Lackner 2013: 281). The comparison of the male genitalia of both species reveals their striking similarities as well (compare figs 2–10 with those of Lackner 2013, figs 11–17) suggesting further support for the genus’ monophyly. The main difference between the male terminalia lies in the shape of spiculum gastrale that in C. chobauti belongs to the most common type found in the Saprininae, having both ‘head’ and ‘stem’ sensu Caterino and Tishechkin (2013). On the other hand, the spiculum gastrale of C. altus is of a rather peculiar type, lacking typical ‘head’ or ‘stem’ (compare figs 7–8 with those of Lackner 2013, figs 14–15). Especially seen from the lateral view, the spiculum gastrale of C. altus is extremely flat, almost without projections (Fig. 8). According to my studies on the morphology of the Saprininae, the shape of the spiculum gastrale is very diverse and it was very difficult to parse this extraordinary diversity into discrete character states (Lackner in press).

Figure 1. 

Ctenophilothis altus (Lewis, 1885) habitus, dorsal view.

Figures 2–10. 

Ctenophilothis altus (Lewis, 1885) 2 – eighth sternite and tergite, ventral view; 3 – ditto, dorsal view; 4 – ditto, lateral view; 5 – ninth and tenth tergites, dorsal view; 6 – ditto, lateral view; 7 – spiculum gastrale, ventral view; 8 – ditto, lateral view; 9 – aedeagus, dorsal view; 10 – ditto, lateral view.

The second known locality of C. altus (Asyut, 27°11’00”N 31°10’00”E) lies more south than the single one published previously (Fig. 11). The presumed rarity of the species can be most likely ascribed by the insufficient collection aimed at the psammophilous Histeridae in Egypt. While efforts aimed at collecting psammophilous Saprininae of the Algerian and Moroccan Sahara yielded remarkable results (see e.g. Olexa 1990 or Gomy et al. 2014), there has been practically no such activity performed in Egypt.

Figure 11. 

Distribution of Ctenophilothis altus (Lewis, 1885) in Egypt.

Thanks are due to the Coleoptera curator of ZMHUB, B. Jaeger for his help and assistance during my visit to the collection as well as to Mahmoud Saleh Saleem (Riyadh, Saudi Arabia) for his help with the Egyptian localities. I would also like to thank the ZMHUB for the help with the open access of my work. This research received support from the SYNTHESYS Project http://www.synthesys.info/, which is financed by the European Community Research Infrastructure Action under the FP7 Integrating Activities Program as well as by the Internal Grant Agency (IGA n.20124364) Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Czech Republic.