The Dromiusina Bonelli, 1810 of southwestern Saudi Arabia with description of a new species (Coleoptera, Carabidae, Lebiini)

Abstract In this paper, species of the subtribe Dromiusina Bonelli, 1810 from southwestern Saudi Arabia are revised. Eleven species in six genera (Calodromius, Dromius, Mesolestes, Metadromius, Microlestes, and Zolotarevskyella) are recognized. Dromius saudiarabicus Rasool, Abdel-Dayem and Felix, sp. n. is newly described species from Rayda Nature Reserve Asir province. The presence of Metadromius ephippiatus in Saudi Arabia is doubtful. A key is also provided to genera and species level for Dromiusina of Saudi Arabia.


Introduction
The Dromiusina Bonelli, 1810 is the third largest subtribe in the tribe Lebiini of the subfamily Lebiinae, encompassing approximately 735 described species (Lorenz 2005). Its members can be recognized by the fused mentum and prementum. Other important characters of these ground beetles are epipleurae incomplete, not passing the text are the National Museum of Natural History, Paris, France (MNHN) and the Museum of Natural History, Hungary (MNH).
For collection of species, light trap (LT), hand Picking (HP), pit fall trap (PT) and sticky trap (ST) were used. Male specimens of freshly collected species were dissected for aedeagus, which is boiled in 70 % KOH for 1-2 minutes to eliminate additional tissues and kept in clove oil for 24 hours. The aedeagus were glued on cards or preserved inside a glycerin vial pinned under specimen.
All the species and aedeagus were photographed by Q-imaging Micro Publisher 5.0 RTV camera, attached with a trinocular stereomicroscope (LEICA MZ125). Taken images were joined by software Zerene Staker 1.04. FEI Inspect S50 model (Scanning Electron Microscope) was used to take scanned images.
Total body length (TBL) was measured from the anterior margin of labrum to terminating margin of abdomen along midline; head length (HL) was taken from anterior margin of labrum to anterior margin of pronotum along middle line, while pronotum length (PL) and elytra length (EL) was taken from anterior to posterior margin along the middle line of pronotum and elytra respectively; head width including eyes (HW), pronotum width (PW) and elytra width (EW) were measured at their widest points. Aedeagus length (AL) was measured along its body mass. All the measurements were taken with an ocular micrometer in a stereo-binocular microscope (МБС-9).
Verbatim label data cited for the type specimens of the newly described species have label breaks indicated by a slash ("/"). The chorotypes of species were designated by following the classification of Taglianti et al. (1999). For synonymy and species distribution, Kabak (2003Kabak ( , 2017, Bousquet (2012), Anichtchenko (2017) (http:// carabidae.org), and available literature are followed.
Ecological notes. This species was collected in the natural habitat of mountains and valleys covered with variety of vegetation, sand, and stones. Species was distributed in elevation ranging from 892-1611 m (Fig. 49). Adult beetles were attracted to UV-light. In winters this species appears in low elevation while in summers it appears in high elevation.
Geographical distribution. This species is recorded from Iran, Libya, Morocco, Saudi Arabia, Tunisia, UAE (Kabak 2003, Felix 2009). In current study it is collected from Al Baha and Asir regions of Saudi Arabia. It is a Mediterranean species that exemplifies Mediterranean-Sindian chorotype.
The genus Dromius is type genus of subtribe Dromiusina, representing 105 species in the world (Lorenz 2005) distributed in four subgenera (Anichtchenko 2017). These species are distributed in almost all zoogeographical regions, Nearctic, Neotropical, Australian, Oriental, Afrotropical, and Palaearctic regions. In the Palaearctic it is represented by 53 species (Bousquet 2012). This genus can be differentiated from other genera in the subtribe Dromiusina by elongate and parallel sided elytra; head small and with constricted neck; labrum semirounded, mentum without tooth; antennae long and cylindrical, pubescence starts from antennomeres IV; base of pronotum straightly truncate, and pronotum sometimes slightly sinuate posteriorly; tarsomeres I-III dilated in fore legs, basal tarsomere of hind legs as long as last, claws dentate; elytra usually with pale macula, apical margins of elytra obliquely truncate (Lindroth 1974, Bousquet 2010. Only D. buettikeri Mateu, 1990  Specific epithet. The specific epithet is a Latinized adjective in the masculine form based on country Saudi Arabia, from which the new species is described.
Diagnosis. Adults of Dromius saudiarabicus sp. n. have all the features of other members of subgenus Dromius Bonelli, 1810 and can be distinguished from them by the following combination of external features: dorsum of head and pronotum rufous to rufo-testaceous, Elytra dark brown, with testaceous maculae, antennae, mandibles, palpi, and legs; head without microlines, but with mesh pattern isodiametric on the vertex, frons smooth; head longer than wide; tempora long with strongly constricted neck; pronotum not strongly transverse, narrowed and sinuate posteriorly before angles.
Description. Habitus: Body form ( Fig. 21) elongate subparallel sized species, TBL Holotype 6.90 mm, male 6.80-7.30 mm, female 7.00-8.00 mm. Color: Dorsum of head and pronotum rufous to rufo-testaceous; antennae, mandibles, palpi and legs testaceous. Elytra dark brown, with testaceous macula suture below scutellum with different expending range, but never reaching middle or lateral border of elytra; epipleurae testaceous anteriorly and dark brown posteriorly; ventrum of thorax testaceous, abdominal sternites dark brown laterally and testaceous medially, sometimes sternites III-V completely dark brown. Microsculpture: Head without microlines, but with mesh pattern isodiametric on the vertex, frons smooth; pronotum with distinct transverse wrinkles medially along the median longitudinal impression, smooth laterally; elytra with mesh pattern isodiametric, microlines absent; thoracic ventrum smooth; abdomen with microlines. Luster: Head, pronotum and ventrum glossy, elytra moderately dull. Head: Small and obtuse (Fig. 12), Holotype HL 1.36 mm and HW 1.16 mm; tempora long with strongly constricted neck; surface smooth with two pairs of supraorbital setae; clypeus smooth, larger than labrum, with a pair of setae; labrum almost as long as wide, rounded laterally, with anterior margins slightly convex; last segments of maxillary and labial palpi pointed; mentum without median tooth; antennae long filiform, extending beyond base of pronotum by three antennomeres; antennomeres I, III and IV equal in length and longer than the rest; antennomeres II shortest; antennomeres V-IX subequal; pubescence starts from antennomere IV. Pronotum: more or less transverse, (Fig. 12) Holotype PL 1.05 mm and PW 1.24 mm; median longitudinal impression deep; narrowed posteriorly, slightly sinuate before basal angles; provided with two pairs of lateral setae; anterior margins of pronotum concave with rounded angles and basal margins straight with almost right angles. Elytra: subparallel sided, Holotype WL 4.10 mm and EW 2.50 mm, broadened in the posterior third; humeri broadly rounded; striae clear; apices of elytra slightly obliquely truncate; epipleurae ends before apical angles of elytra. Legs: Long and slender; protarsomeres I-III dilated in male; tarsomeres I shorter than V in fore legs, tarsomeres I as long as V in median and hind legs; claws with 2-3 tooth in the middle. Abdomen: abdominal sternite smooth, laterally pubescent; suture between III and IV sternite not complete; margins of last two sternite with lateral setae, last sternum emarginated medially in males and rounded in females; males and females with 8 anal setiferous punctures at the apical margin of the last sternum, 4 inner setiferous punctures shorter than outer in females. Aedeagus: Shape of aedeagus (Fig. 38), AL of Holotype 1.50 mm; in lateral view it is narrowed at both ends, broad in the middle, curved dorsally; apical lamina long, narrowed and depressed, rounded apically; basal side rounded and cylindrical.
Affinities. Externally, Dromius saudiarabicus sp. n. is similar to D. buettikeri Mateu, 1990 and D. meridionalis Dejean, 1825, but it can be differentiated from both species by its dull surface, constricted neck, and shape and internal sac of aedeagus. It can also be separated from D. buettikeri by its comparatively less transverse pronotum, sinuate lateral margin of pronotum and tempora long. It is also separated from D. meridionalis by its slightly sinuate lateral margin of pronotum and absence of two ridges near eyes.  Mateu, 1990: 40 Figures 13, 24, 39, 50 Dromius buettikeri Mateu, 1990: 40. Description. Elongate and parallel sized species (Fig. 24), 5.50-6.30 mm. Color: Head, pronotum and basal four sternite light brown in the middle; mouth parts, antennae, legs, anterior 3/4 of epipleurae testaceous; humeri with pale or testaceous macula may extend to middle of elytra; rest of elytra, apical fourth of epipleurae and lateral boarders of elytra, last two abdominal sternite dark brown. Microsculpture: Head, pronotum, elytra with isodiametric mesh pattern; abdomen with depressed microlines. Head: Wider than long, HL 0.92-1.06 mm, HW 1.05-1.12 mm, narrower than pronotum; tempora short and curved (Fig 13). Pronotum: Broad, transverse, PL 0.99-0.92 mm, PW 1.23-1.34 mm, lateral margins almost straight, basal angles right with straight base (Fig. 13). Elytra: Elongate and parallel sized, WL 3.25-3.75 mm, EW 1.87-2.12 mm. Claws with 2-3 teeth in the middle. Abdomen: last two sternite with 8 setiferous setae in females and 4 in males; lateral margins with fine scattered pubescence. Aedeagus: narrowed at both ends, AL 1.09 mm. In lateral view, it is incised in the middle from ventral sides and hump like from dorsal sides, broad in the middle. Tip of apical lamina short and rounded, weakly incised near dorsal margin of apical lamella (Fig. 39).

Dromius buettikeri
Ecological notes. Adult beetles were collected by UV-light from elevation ranges from 1474-1851 m on steep sloop mountains (Fig. 50), characterized by surface vegetation, stones, gravels and small shrubs and trees, this species was collected in December to February in winter season.
Geographical distribution. Endemic to the Saudi Arabia and only found in nature reserve of Rayda mountains in Abha, Asir (Mateu 1990, Kabak 2017.

Metadromius arabicus
Affinities. This species is very close to Metadromius spec. (see below) in general appearance, body form, shape of head, pronotum, and elytra, but can be easily distinguished by its testaceous pronotum, smooth head, transverse band on elytra, and short apical lamina of aedeagus, with an elongate endophallus armature.
Ecological notes. It is collected from low lands to high lands in diverse habitats within 402-2387 m range of altitude (Fig. 51). It is found under stones among vegetation and in sandy ranges, which are influenced by rain water. The species was collected during all months of the year except July.
Geographical distribution. This species is described from Saudi Arabia (Mateu 1979) and distributed in southwest Saudi Arabia, also reported from Iran and United Arab Emirates (Felix 2009, Kabak 2017. It is W-Palaearctic element that exemplifies SW-Asiatic chorotype. elytra, anterior half of epipleurea and antennae testaceous; legs, ventrum of thorax and abdominal sternite pale testaceous; elytra with dark brown pattern covering the posterior half of elytra, leaving the testaceous round spots near apex and suture, suture dark brown throughout. Microsculpture: head, clypeus, labrum, pronotum, and elytra with mesh isodiametric pattern; last abdominal sternum with transverse microlines, rest of the sternites with depressed microlines. Head: As long as wide, narrower than pronotum; HL 0.45-0.52 mm and HW 0.46-0.52 mm; dorsum densely and coarsely punctate (Fig. 15). Pronotum: Transverse, PW 0.55-0.58 mm and PL 0.40-0.44 mm, pronotum narrowed posteriorly with sharp basal angles, base lobate at middle, incised near the angles; dorsum of pronotum densely and coarsely punctate (Fig. 15). Elytra: Subparallel, slightly widened posteriorly, EL 1.34 mm EW 0.95 mm apical margin obliquely truncate, sparsely punctuate, claws dentate. Abdomen: All visible sternite sparsely and finely punctate; last sternum Tetra-setose, incised in males and rounded in females. Aedeagus: It is elongate (Fig. 41), AL 0.45 mm; in lateral view flat throughout, very thin and equally broadened from base to apical end; apical lamina broadened, end strongly rounded.

Metadromius brittoni (Basilewsky, 1948)
Affinities. This species is similar to M. arabicus and M. ephippiatus in general from but it can be differentiated by: densely punctated head and pronotum, presence of microsculptures on whole body, Tetra-setose apical margin of abdominal sternum in male, and apical lamina of aedeagus broad.
Ecological notes. This species is attracted to UV-light. Living from low to high elevated areas from 402-2761 m (Fig. 51). It is collected from various kind of habitats, sand dunes covered with light vegetation, near the water streams and under the shade of small shrubs where it lives with variety of arthropods (Hemipetra, Collembola, Staphylinidae, and spiders), while in valleys of mountains, it is hidden under leaves and stones.
Geographical distribution. It was described from Yemen (Basilewsky 1948), then recorded from Jordan and Saudi Arabia (Mateu 1979, Kabak 2003, Anichtchenko 2017. Metadromius brittoni is Arabian element that exemplifies Arabian chorotype. Notes. These specimens (Figs. 28) are similar to specimens identified by Mateu (1986) from Saudi Arabia as M. ephippiatus (Fairmaire, 1884). However, the specimens of M. ephippiatus known from Algeria are quite different and identification of Mateu, 1986 is doubtful. Most probably the specimens from Saudi Arabia are a new species. As Metadromius in the Middle East is under revision, a species name is not designated here.

Microlestes discoidalis (Fairmaire, 1892)
Affinities. This species is very similar to M. glabrellus (Reitter 1901) in body size, shape of pronotum, large eyes, and short tempora, but can be differentiated by the two large and elongated pale testaceous discal maculae on the elytra and suppressed transverse microlines on the elytra. Endophallus armature of aedeagus elongate and slender.
Ecological notes. The species was attracted to UV-light at low elevated areas to high mountainous areas at 75-1770 m range of altitude (Fig. 52). In day time, it remains hidden under gravels and leaf litter below the shade of small shrubs and vegetation; and can be easily collected by aspirator.

Microlestes glabrellus
Affinities. This species is similar to M. discoidalis in general appearance, elongate and slender, antennae, eyes large with short temples, but can be distinguished by black color of whole body (except tibiae and tarsomeres), strong transverse microlines on elytra, and endophallus armature of aedeagus broad and flat.
Ecological notes. Members of this species were found in steep slopes in Rayda Nature Reserve (Asir Provence). They were collected from 1614-1897 m of elevation (Fig. 52), adult beetles were fly to UV-light. The adults were collected from places covered by different vegetation that dominated by Cactus shrubs Opuntiaficus indica.
Affinities. This species is very close to Microlestes vittipennis J.R Sahlberg, 1908 in general appearance, color, body size and pattern of elytra, but it can be distinguished by: antennomere II as long as III, eyes small with large temples, strongly curved, apical margin and lamina narrow and long; apical end small rounded; internal sacs leaf-like.
Ecological notes. The species was collected from low lands and mountainous areas with 648-2285 m elevation range (Fig. 52). Adults were found under gravels and leaf litter in humid and moist places among mixed vegetation and shrubs. Also, they are attracted to UV-light.
Geographical distribution. This species was described by Matue (1956) from southwestern Saudi Arabia and also reported from Afghanistan and Yemen (Mateu 1979, Kabak 2003. This range exemplifies Afrotropico-Indo-Mediterranean.
Pseudomesolestes Mateu, 1956 Type species. Mesolestes brittoni Mateu, 1956 The genus Pseudomesolestes is a small genus that contains only seven species, distributed in Palaearctic, Oriental, and Afrotropical regions (Anichtchenko 2017). Three species have been recorded from Palaearctic region, two of which are documented from Arabian Peninsula (Kabak 2003(Kabak , 2017. This genus can be distinguished from other genera in subtribe Dromiusina by the following combination of characters: antennae stout, antennomeres II as long as III; pubescence starts from antennomeres II; mentum without median tooth; labrum rounded at anterior margins; maxillary palpi fusiform; pronotum constricted and sinuate posteriorly, base of pronotum straight in the middle, making 45° angle to hind angles; elytra broadened posteriorly, apex of elytra transversally truncates; basal boarder of elytra is complete up to scutellum (Mateu 1956(Mateu , 1984. In Arabian Peninsula, this genus is represented by two species P. brittoni Mateu, 1956 described from Yemen and also recorded from Saudi Arabia, and P. quadriguttatus Matue, 1979 is endemic to Saudi Arabia only. Mateu, 1956 Figures 19, 33, 45, 53 Mesolestes brittoni Mateu, 1956: 66. Type locality. Yemen, Kamaran Island.
Description. Small beetle (Fig. 33) 2.55 mm. Color: frons and vertex black; clypeus, labrum, dorsum and ventrum of head and thorax, mouthparts, elytra, antennomeres I and femora -dark brown; rest of the antennomeres dark brown; elytra with two pale testaceous elongate spots, one after humeri covering intervals IV-VI and second round small spot near apex of elytra, covering intervals IV and V; tibiae and tarsomeres pale testaceous. Microsculpture: Head, pronotum and elytra with granulated microsculptures, clypeus and labrum with transverse lines. Head: as long as wide HL 0.56 mm and HW 0.58 mm as wide as pronotum; tempora short (Fig. 19). Pronotum: Transverse, PL 0.42 mm and PW 0.58 mm, narrowed posteriorly, sinuate before the basal angles, base straight in the middle with weak angles (Fig. 19). Elytra: Widened posteriorly, apical margins transversally truncate; striae II with fine punctures. Claws smooth. Aedeagus: Small (Fig. 45) AL 0.61 mm, in lateral view, aedeagus slightly curved dorsally and ventrally; thick from base to apical lamina; apical lamina narrowed, short and slightly curved before end with a small tooth dorsally; base of aedeagus also with a small tooth.
Affinities. Pseudomesolestes quadriguttatus is the only other specie recorded from Saudi Arabia which is close to P. brittoni in shape of head and pronotum, but can be distinguished by granulated microsculptures on head, pronotum and elytra, wrinkles on dorsum of pronotum along the medial impression; shape of testaceous spots; dark brown femora, aedeagus with single elongate endophallus armature and short apical lamina.

Pseudomesolestes quadriguttatus
Affinities. Pseudomesolestes brittoni is the only other species recorded from Saudi Arabia and is close to P. quadriguttatus in shape of head and pronotum, but can be distinguished by elytra of P. quadriguttatus considerably widened posteriorly with pale testaceous inverted spot at humeri and round spot after middle, legs completely pale testaceous, aedeagus with three elongate endophallus armatures.
Ecological notes. This species was collected from hilly and mountainous zones of 892-2761 m elevation range (Fig. 53). It was collected during day time from root zones of superficial vegetation and small shrubs, while during night it fly to UV-light. The species was collected during January, February, March, September, and December.