Acinopus (Acinopus) brittoni, W & M, 2016

W, David & M, Boris, 2016, Four new species of genus Acinopus DEJEAN, 1821, subgenus Acinopus from southern Iran, from Sinai, and from western Saudi Arabia, and faunistic and taxonomic notes on species previously described (Coleoptera, Carabidae, Harpalini, Harpalina), Linzer biologische Beiträge 48 (2), pp. 1783-1806 : 1797-1800

publication ID	https://doi.org/ 10.5281/zenodo.5356276
persistent identifier	https://treatment.plazi.org/id/A31A87A7-0D13-FFF1-52C5-EBF7FC4E3830
treatment provided by	Marcus
scientific name	Acinopus (Acinopus) brittoni
status	sp. nov.

Treatment

Acinopus (Acinopus) brittoni View in CoL nov.sp. ( Figs 3 View Figs 1-4 , 9, 10 View Figs 9-12 , 15 View Figs 13-16 )

Acinopus sabulosus (FABRICIUS, 1792) View in CoL : BRITTON 1948: 109

T y p e m a t e r i a l: Holotype 6, labelled: "El Hahaz / Milliger [sic]", "El Hedjaz. / Millingen. /1915-38" (both labels black print on white labels), "El Hedjaz." yellow underlined) " Acinopus View in CoL / sp." (handwritten), " Acinopus View in CoL / sabulosus F / Determined from / description. E.B.B." (species’ name handwritten in black by Britton, rest black printed) ( BMNH) . Paratypes: 16, 1♀ with the same first two labels as the holotype, the female additionally with a handwritten label " Acinopus (A.) sabulosus BM View in CoL 313"(subsequently added) ( ZIN, BMNH) ; 366: " Hedjaz " (handwritten in black) and "BMNH" (handwritten, subsequently added) ( BMNH, cWR) ; 1 female with " Hedjaz. Millingen " (handwritten in black) and "BMNH" (handwritten, subsequently added) ( BMNH) ; 1♀: " Hedjaz " (handwritten in black), " Kiesenwetter ", " Sammlung / Cl. Müller " (both labels black print on white label) ( ZSM) .

E t y m o l o g y: The species name is a latinized patronym based on the surname of Everard B. Britton (1912-2004), who made a substantial contribution to our overall knowledge on Carabidae of New Zealand, Hawaii and the fauna of Yemen, and who mentioned a species of subgenus Acinopus occurring in the Arabian region for the first time.

D i a g n o s i s: A brachypterous species of medium to large size for Acinopus , with excision of dorsal edge of right mandible (subgenus Acinopus ), black, tarsomeres and antennae dark reddish-brown, labrum deeply incised at anterior margin, clypeus with one setiferous pore puncture at anterior angles, pronotum laterally toward the obtuse-angled posterior angles almost rectilinearly or very weakly convexly narrowed, apicad weakly convex, anterior angles strongly protruding, narrowly rounded at tip, posterior angles widely rounded at tip, elytra short-oval, somewhat flattened on disc, metepisternum transverse, pro- and mesotarsi in males moderately widened, apical lamella of median lobe short, about somewhat elongate-triangular (dorsal view). Habitus see Fig. 3. View Figs 1-4

D e s c r i p t i o n: Body length 13.4-18.1 mm in males, 15.5 mm in holotype, 15.7- 17.8 mm in females; width 5.8-7.1 mm in males, 6.4 mm in holotype; 6.3-6.9 mm in females.

Colour: Black, tarsomeres and antennae reddish-brown.

Head: wide (as normal in Acinopus ), only somewhat narrower than pronotum (PW/HW in males 1.21-1.26, in holotype 1.23; in females 1.21-1.28). Eyes small and relatively flat, tempora oblique, about half to three fourth as long as diameter of eye (dorsally seen), rectilinearly converging to neck. Frontal foveae mostly small and shallow, sometimes elongately prolonged backwards. Disc smooth, sometimes laterad with widely spaced micropunctures. Excision of dorsal lateral edge of right mandible well developed, almost semicircular, in short distance from base of mandible, proximal (basal) angle of excision situated distinctly anterior to level of anterior margin of clypeus (with mandibles closed). Labrum strongly and somewhat angulately incised at anterior margin (about as strong as in A. sabulosus ), clypeus weakly semicircularly incised, with anterior angles with one setiferous pore puncture each. Mentum tooth small, submentum with one long seta laterally on each side.

Pronotum ( Fig. 3 View Figs 1-4 ): Strong transverse (PW/PL in males 1.70 - 1.77, in holotype 1.73; in the two female paratypes 1.76-1.78), widest at about end of anterior third, there or somewhat before lateral seta inserted. Disc convex, area of posterior angles strongly flattened, anterior and posterior transverse impressions very shallow or only indicated, median line weakly impressed, terminated before anterior margin and sometimes reaching basal margin. Basal foveae short, elongate, distinctly converging basad, shallowly or more strongly impressed, some punctures of unequal size in and around fovae, more or less widely spaced and continuing to the area of posterior angles. Anterior margin a little wider than posterior margin, deeply excavate, anterior angles strongly projecting forward, relatively narrowly rounded at tip. Lateral gutter relatively narrow in small specimens, somewhat wider in larger specimens, sometimes somewhat widened toward anterior angles. Sides moderately curved apicad, almost rectilinear or weakly convexly narrowed from widest point basad. Posterior angles somewhat obtuse-angled, widely rounded at tip. Base almost rectilinear between basal foveae, posterior angles very weakly deflexed backwards.

Elytra ( Fig. 3 View Figs 1-4 ): short-oval (EL/EW in males 1.26-1.32, in holotype 1.30; in the two female paratypes 1.36 and 1.37), only somewhat wider than pronotum (EW/PW in males 1.07-1.14, in holotype 1.08; in the two female paratypes 1.08 and 1.09). On disc only moderately convex, humeri distinctly developed, somewhat angled, rounded at tip, without humeral tooth, not fused at suture, somewhat convexly enlarged toward behind, widest about in middle. Basal bead weakly sinuate, arcuately curving inside humerus and weakly angled or round towards lateral margin. Scutellar pore puncture present, scutellar stria long. Striae fine, smooth, intervals flat on disc, becoming convex toward elytral declivity, interval 3 without pore puncture (holotype, four paratypes), or with a pore puncture at about beginning of apical fourth close to stria 2 (two paratypes). Interval 5 with one or two pore punctures apically, or such lacking on one or both elytra, interval 7 with one to three pore punctures apically, often in different numbers on both elytra. Preapical sinuation weak in males, only suggested in females.

Hindwings: Strongly reduced to small scales.

Ventral surface: Prosternum with short setae, apex of prosternal process with long setae, proepisternum and anterior part of mesepisternum with sparse, fine setae, metepisternum and metasternum (laterally) with sparse, coarse seta-bearing punctures. Metepisternum very short, ratio of anterior margin/internal margin (visible parts) about 1.07, moderately narrowed behind. Abdominal sternites III-V with scattered setae of unequal length. Last sternite, beside some fine scattered setae with two pore punctures bearing a long seta on each side at apical margin in both sexes.

Legs: Normal for Acinopus species. Pro- and mesotarsi moderately widened in males (somewhat weaker than in A. laevigatus ), pro- and mesotarsomere 1 with two small adhesive scales apically, pro- and mesotarsomere 2-4 with biseriate adhesive vestiture. Ventroapical tubercle of protibia with five to eight spines, arranged in a transverse row. Eight to nine spines on lower surface of protibia arranged in one row, sometimes single spines out of the line. Outer distal margin of fore tibia with five to nine spines. Tarsi smooth on superior surface except obligatory setae.

Microsculpture of surface: Head and pronotum in males with slightly transverse meshes weakly engraved and somewhat irregular, elytra with the same kind of meshes but somewhat more strongly engraved than on the forebody, surface very shiny, in females meshes somewhat stronger engraved, surface less shiny.

Median lobe of aedeagus ( Figs 9, 10 View Figs 9-12 ): Of normal construction for Acinopus species. Middle and apical part somewhat bent to the left, terminal lamella wide and flat, somewhat short-triangular, and apically widely rounded (dorsal view), apicad almost rectilinear (lateral view), internal sac with an elongate group of about 20 medium-sized and small spines.

Female genitalia ( Fig. 15 View Figs 13-16 ): Hemisternite asymmetrical, with numerous scattered setae in its internal, somewhat hyaline part. Gonocoxite 1 elongate, apically with numerous setae, gonocoxite 2 scoop-shaped, apically somewhat blunt, with a double-sensilla in a furrow, and with numerous fine long setae at concave side.

I n t r a s p e c i f i c v a r i a b i l i t y The material is too small to make an extended statement on this item. Concerning the eight specimens examined it can be noted that the body size can vary considerably and that the elytra can have or have not one pore puncture in interval 3, with the possibility that only one elytron has this puncture, also the number of pore punctures in interval 5 and 7 can vary.

C o m p a r i s o n s Acinopus brittoni nov.sp. is similar in general habitus to A. sabulosus (FABRICIUS, 1792) . Comparisons of more than 60 specimens of A. sabulosus from Morocco, Algeria, and Tunisia with the specimens of the new species from the Hedjaz region showed that both species have the same number of clypeal setae, a labrum also strongly and somewhat angulately incised at anterior margin, the same position of the excision of the right mandible, a metepisternum very short (in A. sabulosus ratio of anterior margin/internal margin about 1.04 to 1.12), a similar construction of the male pro- and mesotarsomeres, and also a similar external construction of the median lobe of the aedeagus, but revealed some significant differences. A. sabulosus has the pronotal posterior angles more widely rounded, the area of the posterior angles is not or at most weakly flattened, the pronotum and the elytra are much more convex (contour distinctly broken at junction of pronotum and elytra, laterally seen), the hindwings are reduced to small scales, the elytra are fused at suture, and the elongate group of spines of the internal sac of the median lobe consists of more spines (about 20 to 30, rarely less numerous). In A. brittoni spec.nov. the pronotal posterior angles are obtuse-angled, though widely rounded at apex, the body is relatively flat (contour hardly broken at junction of pronotum and elytra, laterally seen), the hindwings are longer (about one third as long as elytral length), the elytra are not fused at suture, and the elongate group of spines of the internal sac of the median lobe consists of spines less numerous (about 20). For differences to A. arabicus nov.sp. see below under A. arabicus nov.sp.

The new species has in common with A. laevigatus , a species extremely variable, the same body colour, the clypeal anterior angles with only one setiferous pore puncture each, the pro- and mesotarsomeres in males are widened about to the same extent, but differs by a larger, shorter and flatter body, by the position of the lateral excision of the dorsal edge of the right mandible (basal angle of excision anterior to level of anterior margin of clypeus) which is situated in about the basal third, the pronotum shorter, by the short-oval elytra with mostly weakly angulate humeri, reduced hindwings and shorter metepisterna, finally also by a somewhat different construction of the median lobe of the male genitalia which is stouter, with an apical lamella shorter, apicad almost rectilinear (lateral view), the internal sac with only one elongate group of about 20 medium-sized and small spines. A. laevigatus has the excision of the dorsal edge of the right mandible somewhat anterior to somewhat behind the middle of the mandible (basal angle of excision behind level of anterior margin of clypeus, but very variable in this aspect), the pronotum as a rule is longer with posterior angles with a suggested angle, though rounded at tip. The elytra are more or less cylindrical and widest behind the middle, the hindwings are fully developed and the metepisterna long (ratio of visible parts of anterior margin/internal margin about 0.71) and strongly narrowed towards behind. The median lobe of the male genitalia is slender, with an apical lamella distinctly longer and distinctly reflext dorsad, the internal sac has a higher number of spines (about 30 to 50, rarely fewer) arranged mostly in two more or less distinct elongate groups.

Acinopus picipes , a macropterous species similar to A. laevigatus in its habitus, differs from A. brittoni nov.sp. by a more convex body, the possession of clypeal anterior angles as a rule with two setiferous pore puncture each, by the position of the excision of the dorsal edge of the right mandible which is inserted shortly behind the base, by the elytra more or less cylindrical and as a rule widest behind the middle, the hindwings are fully developed and the metepisterna long (ratio of anterior margin/internal margin (visible parts) about 0.77) and strongly narrowed towards behind.

H a b i t a t: Nothing is known about the exact localities, biotope, and circumstances of collecting. The Hedjaz region as the northern part of the Sarawat Mountains rises about 2100 meters. It is likely (as in the case of A. arabicus nov.sp., described below) the species lives in higher altitudes with enough moisture, which makes plant growth possible.

D i s t r i b u t i o n: Likely to be endemic to the Hedjaz Mountains in Saudi Arabia. See also the remarks to A. arabicus nov.sp. below.

R e m a r k s: This new species was firstly mentioned as Acinopus sabulosus (FABRICIUS, 1792) from the "Hejaz" ("HEJAZ: 7 ex without detailed record (Millingen)") by BRITTON (1948: 109) in his paper on Cicindelidae and Carabidae collected during the British Museum expedition to South-West Arabia. The name "Hejaz" refers to the modern Al-Hejaz, Hijaz, or al-Ḥiǧāz, a region in the west of present-day Saudi Arabia, forming the northern part of the Sarawat mountain range, which runs parallel to the western coast of the Arabian Peninsula, starting from the border of Jordan in the north to the Gulf of Aden in the south, running through Saudi Arabia and Yemen. The record of A. sabulosus from Yemen ( KATAEV et al. 2003: 368) is based on this erroneous record from the Hejas region made by Britton because it was mistakenly not designated as belonging to the present-day Saudi Arabia but to Yemen. Therefore the distribution of A. sabulosus seems to be restricted only to northern Africa from Morocco, Algeria, and Tunisia to Libya. This species is very variable, it concerns an extreme variability within members of one population as well as geographical variability. There are several names, partly interpreted as synonyms, or as subspecies ( KATAEV et al. 2003: 368), or distinct species (KATAEV & WRASE 2015), a revision is badly needed.