Apristus dioscoridus, Felix, 2017

Felix, Ron F. F. L., 2017, New species and new distributional data on Carabidae (Coleoptera) from the Socotra Archipelago, Acta Entomologica Musei Nationalis Pragae (Acta. Ent. Mus. Natl. Pragae) 57, pp. 41-54 : 47-49

Apristus dioscoridus sp. nov.

( Figs 8–10 )

Type locality. Yemen, Socotra Island, Wadi Mahabat, 12°38ʹ53.2ʺN, 54°08ʹ56.3ʺE.

Type material. HOLOTYPE: J ( RMNH), Yemen, Socotra Island, Wadi Mahabat , 12°38ʹ53.2ʺN, 54°08ʹ56.3ʺE, 25.ii.2009, R.F.F.L. Felix leg. PARATYPES: 8 JJ 7 ♀♀, same data as holotype ( RMNH, RFBE) ; 1 J 1 ♀, Qalansiyah , 12°41ʹ47.5ʺN, 53°29ʹ02.8ʺE, 28.ii.2009, R.F.F.L. Felix leg. ( RFBE) ; 1 ♀, Wadi Ayaft , 12°36ʹ41.1ʺN, 53°58ʹ05.9ʺE, 171 m, 26.x.2010, R.F.F.L. Felix leg. ( RFBE) ; 1 ♀, Wadi Mômi , 12°32ʹ40.3ʺN, 54°17ʹ41.1ʺE, 24.ii.2009, R.F.F.L. Felix leg. ( RFBE) ; 1 ♀, Wadi di Negehen , 12°38ʹ33.0ʺN, 54°03ʹ18.5ʺE, 20.ii.2009, R.F.F.L. Felix leg. ( RFBE) ; 1 ♀, Wadi Irih , 12°27ʹ05.5ʺN, 54°09ʹ16.6ʺE, 3.iii.2009, R.F.F.L. Felix leg. ( RFBE) ; 6 JJ 1 ♀, Wadi between Firmihin and Shibon, 23.vi.2009, L. Purchart leg. ( NMPC) .

Description. Male holotype. Macropterous. Length 3.2 mm. Pronotum transverse, 1.3× wider than long, strongly sinuate and narrowed towards posterior angles.

Colour. Head and pronotum black with greenish lustre. Palpi and antennae brown, gradually lighter apically. Labrum black with yellow borders. Elytra dark reddish brown with dark metallic lustre, especially along lateral margin and suture ( Fig. 8 ). Epipleura red. Legs with brownish black tibiae, femora red with dark apex, tarsomeres red with somewhat darker apex.

Sculpture and structures. Head with isodiametric microsculpture distinct but suppressed, shiny, with dispersed micropunctures. Pronotum shiny, with rather suppressed isodiametric microsculpture and some micropunctures; base somewhat rugose, front part with few shallow wrinkles and bigger punctures. Elytra shiny, microsculpture consisting of slightly transverse meshes. Scutellum with very distinct isodiametric microsculpture.

Head with two supraocular setae bearing pores, second one posterior to eyes, which are rather flat. Temples oblique. Labrum with six setae, its anterior margin slightly incised. Clypeus with two setae, frons border weakly concave. Antennomeres pubescent from III on, length/width ratio of antennomeres IV–VI = 3.5 each; antennomere I with usual preapical long seta and some additional tiny setae, antennomere II with few additional small setae as well. All maxillary palpomeres and apical labial palpomere multisetose, penultimate labial palpomere with two setae.

Pronotum. Front margin weakly concave, almost straight. Anterior angles very small, weakly but distinctly protruding. Posterior angles small and sharp, clearly protruding. Setae bearing pores in posterior angles and on widest point of pronotum. Base straight till shortly obliquely cutting to posterior angles. Basal furrows absent. Marginal gutter narrow throughout its length, narrower than median furrow which is wide and gutter like, not reaching base nor apex. Pronotum widest in its anterior fourth.

Elytra. Prescutellar pores present. Striae shallow, shallower towards sides, but still visible at apex. Intervals weakly convex, covered with scattered setae, less dense on disc, more towards sides and apex. Two seta bearing pores on interval III, mostly near stria III.

Tarsomeres pilose. Onychium with ventral bristles. Claws smooth. Meso- and metatarsomeres I as long as II and III together, apical meso- and metatarsomere as long as III and IV together. Tooth of mentum absent.

Aedeagus, see Fig. 9 .

Variability. Female stylomeres, see Fig. 10 . Paratypes vary in length from 3.2 mm to 3.5 mm. The greenish lustre on head and pronotum can vary a bit in intensity.

Differential diagnosis. In the adjacent regions, the following four species of Apristus Chaudoir, 1846 are known: A. latipennis Chaudoir, 1878 from Ethiopia till South Africa, A. subovatus Chaudoir, 1876 from Yemen mainland, Ethiopia and Somalia. A. boldorii ( Straneo, 1943) (= A. rudicollis Basilewsky, 1948 ) from Yemen mainland, Egypt, Eritrea and Kenya and A. arabicus Mateu, 1986 from the Arabian Peninsula.

The new species differs from all species mentioned above by its all over shining appearance because of the less pronounced microsculpture. The length of both antennomere IV and metatarsomere I is longer than in other species. In addition, A. dioscoridus sp. nov. differs from A. latipennis and A. subovatus by its smaller eyes, longer temples and all over gutter-like median pronotal furrow; and from A. boldorii and A. arabicus by its more sharply delimited temples and neck, and its brown-red colour: A. boldorii is light red and A. arabicus is brownish yellow. Shape of the aedeagus in the new species differs from that in A. arabicus , as it has a less conical apex and somewhat different inner structure; in A. latipennis the ventral border of the median lobe of the aedeagus is almost straight and the length of the apex of the median lobe is twice or more as long as the width; the median lobe of the aedeagus of A. boldorii is slender and over all its length of almost equal width; in A. subovatus the apex of the median lobe is much shorter than in the new species: length almost equal as width.

The Socotran species was also compared with A. reticulatus Schaum, 1857 , known from Italy, Bulgaria, Albania, Greece, Turkey, Uzbekistan, Kyrgyzstan and Iran ( KABAK 2003), because of its resemblance. However, A. dioscoridus sp. nov. differs from A. reticulatus in the following aspects: head and pronotum black with more or less green metallic lustre (head and pronotum dark brown with very weak bronze lustre in A. reticulatus ); anterior angles of pronotum more or less pointed (broadly rounded in A. reticulatus ) femora light brown with black apex, tibia black (femora brown with tibia somewhat lighter in A. reticulatus ); antennomeres short; antennomere I somewhat reddish, other antennomeres black (antennomere I & II red brown, other antennomeres dark brown in A. reticulatus ); upper side more shiny; apex of aedeagus narrower, ventral margin in lateral view of aedeagus straight (bulgy in A. reticulatus ).

A key to distinguish the new species from the above mentioned taxa is provided.

Etymology. The specific epithet refers to the presence of the species in the island of Dioscoridus, an ancient name for Socotra; a noun in nominative case.

Collection circumstances. All specimens were collected in the gravel on the banks of streams.

Distribution. A species endemic to Socotra Island.

Figures

Figs 7–12. 7 – Glycia socotrana sp. nov., female stylomeres. 8–10 – Apristus dioscoridus sp. nov.; 8 – habitus; 9 – median lobe of aedeagus is lateral view; 10 – female stylomeres. 11–12. Mesolestes niger sp. nov. 11 – habitus; 12 – median lobe of aedeagus is lateral view. Not in scale.