A review of the powderpost beetle genus , Xylopertha Guérin-Méneville , 1845 , with a new species and new synonymy ( Coleoptera : Bostrichidae : Bostrichinae : Xyloperthini )

Abstract. We review the three species currently placed in the genus Xylopertha Guérin-Méneville, 1845, and describe a new species, Xylopertha elegans sp. nov., from Turkey. We propose the following new synonymy: Xylopertha Guérin-Méneville, 1845 (= Paraxylogenes Damoiseau, 1968); Xylopertha reflexicauda (Lesne, 1937) (= Paraxylogenes pistaciae Damoiseau, 1968). We give details of the sexual dimorphism, and summarise information on the distribution and biology of all species. A key to the species of Xylopertha is provided.


Introduction
The tribe Xyloperthini Lesne, 1921 is the most species-rich in the Bostrichidae Latreille, 1802, and currently includes 34 genera (Borowski & Węgrzynowicz 2007;Park et al. 2015;Liu et al. 2016a).The tribe has a worldwide distribution, but the individual genera are mostly confi ned to a single zoogeographical region or subregion (Borowski & Węgrzynowicz 2007).
In this paper we review the three species currently included in Xylopertha, and describe one further species, X. elegans sp.nov.We synonymise Paraxylogenes Damoiseau, 1968 with Xylopertha, and Paraxylogenes pistaciae Damoiseau, 1968 with X. refl exicauda.We also provide a key to the four species now included in Xylopertha.

Material and methods
In the course of this study, the senior author has examined all available types, and other specimens of Xyloperthini in the Paris Museum, other European museums, and certain private collections.We have examined type materials or reliably identifi ed specimens of 31 out of 34 genera included in the tribe, and have checked the descriptions of the remaining three genera.
The following abbreviations are used for Museums and other collections: The descriptions of the species are mainly based on Lesne (1901Lesne ( , 1937)), with additional characters obtained from the examination of specimens from the museums and collections listed above, and dissection of specimens in LYL.

Diagnosis
Xylopertha is the type genus of Xyloperthini Lesne (1921).The tribe is characterised by the lamelliform intercoxal process of the fi rst abdominal ventrite, and the mandibles crossed at the tips (Lesne 1921;Fisher 1950;Liu & Schönitzer 2011).The genus is distinguished from all other genera of Xyloperthini by the following combination of characters: frons with upwardly directed hairs (Fig. 2); antenna with nine antennomeres, the funicle with four and the club with three antennomeres, antennomeres of club lacking stiff, erect hairs, with indistinct sensory impressions near the apex of antennomeres 7 and 8, but absent on the last antennomere; pronotum without a lateral carina; elytral suture raised on declivity, but not strongly swollen; last ventrite of male with pleural pieces at sides; last ventrite of female emarginate.
European Journal of Taxonomy 380: 1-22 (2017) strongly impressed in middle; clypeus transverse, fi nely and densely punctured; labrum transverse with a fringe of long hairs along anterior margin.Mandibles subequal, sharply pointed.Eyes small, oval, strongly projecting.Antenna with 9 antennomeres, fi rst antennomere elongate, about twice as long as oval second, antennomeres 3-6 forming a loose funicle, each antennomere transverse, the fi fth widest, together about as long as fi rst antennomere of club, antennomeres 7-9 forming the elongate, compressed club, each antennomere of club with a dense covering of short, recumbent hairs, lacking distinct, clearly defi ned sensory impressions on all segments, antennomeres 7 and 8 subquadrate, subequal in length, last antennomere more elongate, oval.
LEGS.Subequal in length, procoxae contiguous, mesocoxae narrowly separated, protibiae grooved on external face, widened to apex, posterior tibiae with long hairs on outer side.Second and third segments of tarsi usually distinctly wider than the following segments.

Sexual dimorphism
The genus shows strong sexual dimorphism in both the vestiture of the frons, and in the form and sculpture of the elytral declivity (except in X. refl exicauda), as well as in the genitalia.In the female the frons is more densely and fi nely punctured, and the upwardly directed hairs are much longer and denser than in the male.In the male, the elytral declivity is more angularly separated from the disc, and the elytral apices are either conjointly rounded or separated by a small V-shaped emargination.In the female, the disc curves more evenly into the declivity, and the elytral apices are strongly emarginate, the emargination partly fi lled by a pair of ventrally-directed processes (Fig. 3A-C) (except in X. refl exicauda; Fig. 3D).The last abdominal ventrite of the male has pleural pieces which converge posteriorly towards the midline; these are absent, and the last ventrite is emarginate in the female.

Distribution
Southern and central Europe, North Africa and Middle East.

Biology
The adults of Xylopertha are polyphagous, usually attacking a taxonomically wide variety of host trees, although they may appear to show some host preferences.They bore into twigs and branches, where they construct a short gallery, usually consisting of a circumferential and one or more longitudinal branches in which the eggs are laid (Liu et al. 2008).The larvae bore through the wood making extensive galleries fi lled with fi ne wood particles and excreta.The new generation of adults emerges through the bark, but may reattack the same stem, so that the whole of the sapwood is eventually converted into fi ne powder  (Olivier, 1790).B. X. elegans sp.nov.C. X. praeusta (Germar, 1817).D. X. refl exicauda (Lesne, 1937).Scale bar = 1 mm.
LIU L.-Y. & BEAVER R.A., A review of Xylopertha, with a new species (Liu et al. 2008).The development time is variable depending on local conditions, and may vary from a few weeks to over a year (Beeson & Bhatia 1937).

Etymology
The specifi c epithet 'elegans' used by Vrydagh, is from the Latin word for 'elegant' or 'handsome'.

Material examined
Vrydagh selected a holotype, allotype and four paratypes from SNSD, and one paratype from ZMHB.However, the holotype and allotype he selected are in poor condition, and we have accordingly selected a new holotype and allotype in better condition from the same series.

Description
Male BODY.4-5 mm long, about 3.5 times as long as wide.Head, pronotum and ventral side black, elytra dark reddish brown, antennae, mid-and hind-legs paler.
HEAD.Clypeus fi nely punctured, with a pair of small rounded projections on either side of mid-line, slightly emarginate laterally.Fronto-clypeal suture distinct, with a median fovea.Frons simple with sparse, fi ne punctures, each puncture with an upwardly-directed short hair, a pair of very long hairs on each side near the eyes directed towards the midline.Antennae 9-segmented, segments 3-6 together slightly shorter than last segment of club, fi rst and second segments of club slightly wider than long, with small, indistinct areas of dense sensillae, third segment more elongate, and longer than previous segments, without areas of dense sensillae.
PRONOTUM.About 1.1 times wider than long, anterior margin slightly concave, sides quite strongly rounded, widest in basal third, anterior slope quite strongly granulate-punctate in middle above head, without long hairs antero-laterally, disc shining, with very sparse, fi ne punctures bearing very short hairs.
LEG. Anterior tibiae broadly grooved on external face.Second and third segments of tarsi distinctly wider than the following segments.

Female
BODY.Generally similar to male, but differentiated as follows.
HEAD.Clypeus and frons more densely punctured, the punctures with very long yellowish hairs directed towards vertex and partly concealing surface.
PRONOTUM.Anterior face of pronotum wider, very densely, fi nely punctured, above the head the punctures with very fi ne, very long, upwardly directed hairs, discal punctures slightly larger and denser.
ELYTRA.2.6-2.9 times as long as wide, elytral puncturation coarser and denser, disc gradually curving into declivity in apical quarter, declivity very steep, deeply grooved on either side of the raised suture (Fig. 1B), the sides gibbous without a spine or tubercle, the apex of each elytron projecting as a broad approximately rectangular process, its apex with a small pointed tooth next to the suture, the processes separated by a shallow U-shaped emargination, a broad emargination lateral to each process, the edge of the emargination with a fringe of short hairs (Fig. 3C).
ABDOMEN.Abdominal 3 rd ventrite projecting medially over 4 th ventrite, which is only visible at sides, 5 th ventrite very deeply, broadly emarginate, the base of the emargination projecting ventrally as a thin lamina behind the process on the 3 rd ventrite and concealing the middle part of the 4 th ventrite (Fig. 4B).

Xylopertha refl exicauda
We have examined male and female syntypes of Xylopertha refl exicauda from Pakistan (MNHN), the holotype male, allotype female, and three female paratypes of Paraxylogenes pistaciae from Iraq and Pakistan (NHMUK, IRSNB), and further specimens from South Europe and Middle Asia in LYL, NMPC and IRSNB.It is clear that only a single species is represented, and P. pistaciae is here synonymised with X. refl exicauda.Buse et al. (2013) listed P. pistaciae as a synonym of Paraxylogenes refl exicauda [sic] in a paper on the ecology of oak wood-inhabiting beetles in Israel, but made no further comments, and gave no indication that they had examined type material.The synonymy of the only species of Paraxylogenes with X. refl exicauda automatically makes Paraxylogenes a synonym of Xylopertha.
We note below that the male and female genitalia of X. refl exicauda differ in several respects from those of the other species of Xylopertha.However, we do not consider these and other morphological differences suffi cient to retain Paraxylogenes as a distinct genus from Xylopertha.

Diagnosis
Distinguished from Xylopertha elegans sp.nov.and X. retusa (Olivier, 1790) by the presence of a spine on each elytron in both sexes, the spines smaller in the female.Xylopertha refl exicauda differs from X. praeusta in the position of the spines, which are located on the middle of the upper margin of the declivity in X. refl exicauda, whereas in X. praeusta they are located on the dorso-lateral margin of the declivity (Fig. 1E-H).Xylopertha refl exicauda is also distinguished from the other three species of Xylopertha by the absence of any sexual modifi cation of the apical margin of the elytra.The male and female genitalia differ in certain respects from those of the other three species.The posterior margin of the 8th tergite of the male is sclerotised in X. refl exicauda (Fig. 5G), but membraneous in the other three species (Fig. 5A, C, E).The posterior margin of the last ventrite of the male is bidentate without a median lobe in X. refl exicauda (Fig. 5H), but has a median lobe and a process on either side in X. elegans sp.nov.(Fig. 5F) and X. retusa (Fig. 5B).In X. praeusta (Fig. 5D), the posterior margin is bilobed and lateral processes are present.The aedeagus of X. refl exicauda has a pair of long apophyses (Fig. 5H), but the apophyses are absent in the other three species (Fig. 5B, D, F).The last ventrite of the female of X. refl exicauda has a strong median ridge (Fig. 4D), which is absent in the other three species (Fig. 4A-C).

Material examined
For Xylopertha refl exicauda (Lesne, 1934):  The specifi c identity of more than 70 further specimens was checked in the following museums: IRSNB and MAIC under X. refl exicauda; NHMUK and NMPC under Paraxylogenes pistaciae, but detailed locality data were not recorded.All specimens came from the distributional area given below.
HEAD.Above fi nely punctured, with erect, grey or reddish setae (denser and longer in female), eyes moderate, similar in both sexes; antennae 9-segmented, segments 3-6 very small, 7-9 forming the club, biconvex, subglabrous, sensory impressions scarcely visible, penultimate segment slightly transverse.PRONOTUM.Subquadrate, about 1.1 times wider than long, the sides weakly curved, widest at middle, with long hairs antero-laterally, anterior angles armed with small, sharp-edged and pointed teeth, the apex not uncinate; posterior part of disc very fi nely, sparsely punctured.
ABDOMEN.Last ventrite whole, pleural parts very distinct.The posterior margin of the 8 th tergite of the male is sclerotized, margin of the last ventrite of the male is bidentate without a median lobe (Fig. 5H).The aedeagus has a pair of long apophyses (Fig. 5H).

Female
ELYTRA.Apical declivity of elytra with larger punctures in upper part, laterally not marginate, spines on upper margin smaller than in male, apical margin entire.
ABDOMEN.The last ventrite with a deep incision apically, anterior to the incision a very short, high, longitudinal carina, its summit knife-like, its sides with very long, stiff, red setae standing perpendicular to the carina (Fig. 4D), the surface of the sternite with similar hairs.

Diagnosis
The species is easily separable from X. praeusta and X. refl exicauda by the absence of spines on the elytra in both sexes.The male can be separated from X. elegans sp.nov.by the presence of long, erect hairs on the upper margin of the elytral declivity (absent in X. elegans sp.nov.), and by the form of the 8 th tergite and genitalia (Fig. 5A-B: X. retusa; Fig. 5E-F: X. elegans sp.nov.).In the female of X. retusa, the apex of each elytron is strongly emarginate, the emargination fi lled by a pair of ventrally-directed processes with rounded tips next to the suture (Fig. 3A); in X. elegans sp.nov., the apex of each elytron projects as a broad, approximately rectangular process, its apex with a small pointed tooth next to the suture, the processes separated by a shallow U-shaped emargination, a broad emargination lateral to each process (Fig. 3C).In the female of X. retusa, the fourth ventrite is visible across its entire width, and the base of the emargination of the 5 th ventrite does not project ventrally (Fig. 4A); in X. elegans sp.nov., the 3 rd abdominal ventrite projects medially over the 4 th , which is visible only at the sides, and the 5 th ventrite is very deeply, broadly emarginate, the base of the emargination projecting as a thin lamina behind the process on the 3 rd ventrite (Fig. 4B).The specifi c identity of more than 800 further specimens was checked in the following museums: IRSNB, MAIC, MIZPAN, MNB, MTM, NHMUK, NMBS, NMPC, NMS, NMW, SDEI, SNSD, ZNHB and ZSM, but detailed locality data were not recorded.All specimens came from the distributional area given below.

Description
BODY. 3-6 mm long, about 2.8-3.0 times as long as wide, elongate.Black or dark brown, moderately shiny, antennae and tarsi reddish, the posterior part of the elytra often paler.
HEAD.Clypeus fi nely and densely punctured, not convex in front.Frons with puncturation less fi ne and less dense than the clypeus, slightly rough, and covered by fairly long, fi ne pubescence directed upwards.First and second segments of antennal club as wide as long.
PRONOTUM.Slightly wider than long, fairly strongly narrowed in the anterior third, bearing golden, long, erect pubescence on the anterior angles; area above head fi nely and more or less roughly punctured; median and posterior areas shiny with fi ne, sparse puncturation; sides evenly rounded; posterior angles rounded; widest in basal part.
ELYTRA.1.8-2.2times longer than wide, parallel-sided at disc and widest at middle of declivity.Elytral disc moderately dense puncturation, not coarser posteriorly.Upper margin of the elytral declivity bearing reddish, quite long erect pubescence, denser in the male.Elytral suture projecting on declivity, more strongly towards the apex.Elytral declivity without spines on each elytron in both sexes.
LEGS.External face of the anterior tibiae broadly grooved, not narrowed towards the apex.Segments 2 and 3 of anterior tarsi distinctly wider than the others.Male ELYTRA.Widened posteriorly.Upper margin of elytral declivity bearing long, erect pubescence.Elytral suture not raised on disc, strongly raised on declivity.Declivity rather fi nely punctured in the upper half, almost impunctate below, sometimes transversely ridged on much of its surface.Apical declivity larger than in female, more sharply truncate, a little concave, bordered on the lower-lateral side by a carina not extending to the sutural angle, the carina expanded at the sides of the declivity to form a marginal callus.Sutural angles pointed, conjointly projecting or weakly separated at the apex (Fig. 1C-D).
ABDOMEN.Anterior margin of 8 th tergite fringed by long erect outwardly directed hairs.Genitalia strongly sclerotised, with extended lobes laterally, fringed with long hairs at apex and on a small inwardly projecting lobe towards base on each side.Aedeagus simple, without long apophyses (Fig. 5A-B).

Female
HEAD.Frons covered by longer, denser upwardly directed hairs than in male.
ELYTRA.Parallel, suture strongly raised on declivity.Declivity strongly and densely punctured with a truncate raised area at apical third.Lateral margin of declivity sinuate.Apex of each elytron strongly emarginate, the emargination fi lled by a pair of ventrally-directed processes with rounded tips next to suture (Fig. 3A).
European Journal of Taxonomy 380: 1-22 (2017) ABDOMEN.Third abdominal ventrite not projecting medially over 4 th , which is visible across its entire width; 5th segment longer than 2 to 4 together, strongly, longitudinally grooved in the middle, and provided on its posterior margin with two large teeth, contiguous at the base, strongly pointed, and slightly recurved dorsally near the apex; on the outer side of the teeth the posterior margin of the segment is semicircularly emarginate (Fig. 4A).

Distribution
Central and southern Europe, North Africa (except Egypt), Cyprus, Israel, Turkey, Iran, part of Caucasia and Siberia (Liu et al. 2016b).

Biology
The species has been recorded from the wood of trees in the families Fabaceae, Fagaceae, Moraceae, Ulmaceae Mirb.and Vitaceae Juss.(Lesne 1901;Bahillo de la Puebla et al. 2007;Marković & Stojanović 2012;Buse et al. 2013).The species is active from May to July in Southern Europe (Cymorek 1961 as Xylonites retusus; Bahillo de la Puebla et al. 2007), but from October to December in Israel (Buse et al. 2013).In Central Europe, the beetles prefer boring into dry oak branches; the larvae tunnel particularly in the sapwood; they overwinter in diapause and pupate in spring (Cymorek 1961 as Xylonites retusus).Several clerid and a melyrid predators (Coleoptera: Cleridae, Melyridae) are listed by Bahillo de la Puebla et al. (2007).Yu et al. (2012) list three species of braconid Hymenoptera as parasitoids.
Xylopertha praeusta (Germar, 1817) Figs The type material of X. praeusta was not located, but the species is well known in the Mediterranean area.
The senior author has examined numerous specimens determined by Lesne and Vrydagh, and numerous other specimens in IRSNB, LYL, MAIC, MNB, NHMUK, SDEI, SNSD and ZMHB, from various countries in southern Europe and North Africa.Borowski & Singh (2017) examined the type series of Xylopertha dunensis deposited in IFRI, and synonymised X. dunensis with X. praeusta.They state that the specimens in the type series came in fact from Tulon [sic] (correctly Toulon), S-France.It has become apparent that K. Rai falsifi ed the type location of several species that he described (Borowski & Singh 2017).India should, therefore, be excluded from the distribution of X. praeusta.If the species does occur in India, it is almost certainly introduced.

Diagnosis
The species is distinguished from X. elegans sp.nov.and X. retusa by the presence of a spine on each elytron in both sexes (Fig. 1).It is distinguished from X. refl exicauda by the position of the spine, which is on the dorso-lateral margin of the declivity in X. praeusta, but on the middle of the upper margin of the declivity in X. refl exicauda.Differences in the abdomen and genitalia are illustrated in Figs 4 and 5.The specifi c identity of more than 260 further specimens was checked in the following museums: IRSNB, MAIC, MIZPAN, MNB, MTM, NHMUK, NMBS, NMPC, NMS, NMW, SDEI, SNSD, ZNHB and ZSM, but detailed locality data were not recorded.All specimens came from the distributional area given below.
HEAD.Clypeus fi nely and densely punctured, convex along its anterior margin, its median truncation as wide as base of labrum.Frons with puncturation less dense than clypeus, covered by fairly long, upwardly directed hairs.First and second segments of antennal club slightly elongate.Fifth antennal segment often nicked on external side, but this is not constant, nor particular to one sex.Pronotum about 1.1 times wider than long, narrowed in anterior third, without long hairs antero-laterally, area above the head fi nely punctured.
ELYTRA.Puncturation dense and strong on whole of disc; elytral declivity with a tubercle-like spine with a pointed apex located on dorso-lateral margin of declivity of each elytron (Figs 1E-F, 3B); pubescence of apical declivity short, erect, reddish, especially noticeable near upper margin where formed of longer hairs.
LEGS.External face of anterior tibiae narrowly grooved, widened to apex.Second and third segments of anterior tarsi scarcely wider than the following ones.
Male ELYTRA.Apical declivity larger than in female, covered by an exceedingly fi ne and dense puncturation, and often wrinkled in its upper part; elytral spine robust, directed inwardly, strongly bulbous on outer side at base, narrow and very pointed at apex, below it a broad fl ange beginning at sutural angle and extending at sides to about level of lateral spine; sutural angles not projecting, rounded at apex (Fig. 1E).
ABDOMEN.Anterior margin of 8 th tergite wider and fringed by shorter erect hairs than in X. retusa.Genitalia more strongly sclerotised than in X. retusa, with pair of ventrally-directed processes with pointed tips next to inner lobes which are separated by a U-shaped emargination in middle.Aedeagus simple, without long apophyses (Fig. 5C-D).

Female
ELYTRA.Declivity less distinctly truncate than in the male, strongly punctured, the lateral spines smaller, or replaced by tubercles; suture infl ated on the declivity (Fig. 1F).Apical emargination of elytra broad, the emargination largely fi lled by a pair of ventrally-directed, extended processes with rounded tips next to suture (Fig. 3B).
ABDOMEN.Last visible segment of abdomen densely pubescent on sides, not grooved in middle; posterior margin of segment armed by two dorsally recurved large median teeth (Fig. 4C).setae cover the whole frons, and are upwardly directed, the posterior margin of the female elytra is strongly emarginate, and the female fi fth ventrite is variously modifi ed.It seems likely that Enneadesmus, Scobicia and Xylogenes evolved a nine-segmented antenna independently from Xylopertha and Psicula.Here, we compared the characters of Xylopertha, Psicula and two other genera, Xylobosca Lesne, 1901 andXylionulus Lesne, 1901, that appear to be related to Xylopertha, in Table 1.

European Journal of Taxonomy
Xylobosca is distinguished from the other genera considered here by the form of the protibia, which is atypical for Xyloperthini, widest towards the middle rather than at the apex, and lacking a fl at external face.Xylionulus differs from Xylopertha especially in characters of the antennae, the vestiture of the frons and pronotum, and the lack of strong sexual dimorphism.Psicula is the genus most similar to Xylopertha morphologically (Table 1), with very similar characters of the antennae, frons, pronotum and elytra, but the male lacks the pleural pieces on the fi fth abdominal ventrite that are present in Xylopertha.The two genera also have nearly adjacent geographical distributions, Xylopertha extending through the Mediterranean region as far East as Pakistan, and Psicula recorded in North-East India (Sikkim, West Bengal).
The tribe Xyloperthini is greatly in need of revision and further phylogenetic analysis.There are at present no molecular studies of any tribe of Bostrichidae, and much progress may be made in the future using molecular methods.Liu & Schönitzer (2011) suggest that the tribe Xyloperthini is polyphyletic, but their study included only nine genera.A study including as many genera as possible is needed.The geographical distribution of the tribe covers all zoogeographic regions except the Arctic-Siberian, although most species occur in the Palaearctic and Afrotropical regions.A preliminary analysis of the phylogeography of the family suggests that it originated in Gondwana rather than Laurasia (Liu 2016).The genera currently included in the tribe Xyloperthini appear to have multiple geographical origins (Liu, unpublished), again suggesting polyphyly.The present paper is the second in a larger project which will try to resolve some of these problems.
Photographs were taken with a Panasonic Lumix GX8 digital camera, combined using the program CombineZP, and optimized with Adobe Photoshop CS2.
Lesne, 1901inguished by the strong swelling of the suture on the elytral declivity in both sexes, and the last ventrite of the female is entire not emarginate; Psicula Lesne, 1941 is distinguished by the presence of an uncus on the anterior angles of the pronotum in both sexes, and the absence of pleural pieces in the male; Enneadesmus Mulsant, 1851 and XylogenesLesne, 1901have distinctly delimited sensory areas on the fi rst two segments of the antennal club, and the females of Enneadesmus have the last ventrite entire.The synonymy of Paraxylogenes with Xylopertha is discussed later in the paper.