Orphilus aegeanus, Holloway & Herrmann, 2023

Holloway, Graham J. & Herrmann, Andreas, 2023, Orphilus aegeanus (Coleoptera, Dermestidae, Orphilinae): a new species from Greece and Turkey, Zootaxa 5244 (2), pp. 197-200 : 197-199

Orphilus aegeanus sp. nov.

Specimen examined. Holotype: Orphilus aegeanus sp. nov. Greece, Larissa , Thessalia (39.63N, 22.42E) 8 July 2002 A. Herrmann leg. Holotype male BNHM . Paratypes 9 males: Turkey, Kemer (36.60N, 30.56E) 19 May 1996, Lars O. Hansen leg. (3 specimens), Greece, Peloponnese, Menalo (37.54N, 22.31E), 11 June 2001, Josef Louda leg. (1 specimen), Greece, Thessalia (39.63N, 22.42E), 8 July 2002, A. Herrmann leg. (4 specimen), 10 July 2002 A. Herrmann (1 specimen),

External characteristics. Mean BL = 3.45± 0.37mm (holotype = 3.25mm), mean BW = 2.17± 0.21mm (holotype = 2.1mm) ( Fig. 1A ). Holotype description: head with one median ocellus on vertex. Cuticle black. Surface of body glabrous and covered in punctures. Distance between punctures on elytra = width of punctures. Punctures on thorax slightly smaller, distance between punctures = 1.5 times width of punctures. Microstructure on cuticle between punctures. Scutellum triangular and black with punctures on anterior central part of scutellum with lateral margins to posterior tip unpunctured and shining. Elytra with pronounced humeral calli. Legs black. Antennae and palps red. Antenna with 11 antennomeres, and with well-defined three-segmented club ( Fig 1B ).

Internal characteristics. Aedeagus shown in Fig 2A . Parameres broad. Outer margins of parameres almost parallel for majority of length before angling in sharply to paramere tips. Tips of parameres pale contrasting with otherwise chestnut brown coloration. Tips of parameres almost totally glabrous on ventral surface, at most a few small, scattered setae ( Fig 2B ). Tip of median lobe ( Fig. 2B ) carrying a small, upturned, sharp tooth on ventral surface. Median lobe narrowing to rounded tip that extends well beyond tooth such that the angle between the median lobe and the tooth is 90 o or less.

The Palaearctic Orphilus spp. are similar externally so require dissection for definitive identification. The male genitalia of O. niger and O. beali are described elsewhere ( Zhantiev 2001) and will not be confused with O. aegeanus . The likely confusion species on dissection is O. africanus . Fig 3A shows an aedeagus of O. africanus . The parameres are narrower and the outer margins of the parameres bulge outwards slightly about halfway before curving smoothly inwards towards the tips. There is no clear angle in the outer margins of the parameres as shown by O. aegeanus . In addition, the paler coloration at the tips of O. africanus parameres extends further back than O. aegeanus parameres. The tips of the parameres carry obvious setae on the ventral surface ( Fig 3B ). Orphilus africanus median lobe is shown in Fig 3B . The median lobe does not narrow to the rounded tip and is blunter than in O. aegeanus . The tooth is joined to the median lobe very close to the tip such that the angle between the tip of the median lobe and the tooth is greater than 90 o.

This study focusses on male genitalia. More work is required to definitively allocate variation in ovipositor structure to the different species. Orphilus africanus is currently known only from Spain and Morocco, whilst O. aegeanus have been collected from Greece and Turkey. It is possible that O. africanus has a western Mediterranean distribution and O. aegeanus only occurs in eastern Mediterranean. Although the aedeagi of the two species described here differ substantially in structure, geographic distribution might be a very easy way of allocating species.

The tooth on the ventral side at the end of the median lobe in both O. africanus and O. aegeanus has not been noted before as far as we are aware. Researchers have worked with Orphilus in the past but usually remove soft tissue from the genitalia using aggressive cleaners such as KOH, or pepsin which targets proteinaceous structures. The tooth on the median lobe is soft and most likely protein which would not survive treatment with KOH or pepsin. In this study we only used weak acetic acid to soften specimens for dissection which is the most likely reason why the tooth survived intact on the median lobe.

The discovery of O. aegeanus brings the number of known Orphilus species to seven.

Etymology: the species name aegeanus refers to the location of discovery in the proximity of the Aegean Sea.

Figures

FIGURE 1. Orphilus aegeanus holotype A: habitus dorsal aspect, male, scale bar = 1mm, B: antennal club, scale bar = 0.2mm

FIGURE 2. Orphilus aegeanus holotype A: aedeagus dorsal surface, B: median lobe lateral aspect illustrating shape of tip of lobe, position of ‘tooth’ on ventral surface of lobe, and lack of setae on ventral surface of paramere tips, scale bars = 0.2 mm

FIGURE 3. Orphilus africanus A: aedeagus dorsal surface, B: median lobe lateral aspect illustrating shape of tip of lobe, position of ‘tooth’ on ventral surface of lobe, and setae on ventral surface of paramere tips, scale bars = 0.2 mm