Aristopus LaFerté-Sénectère, 1853

Fedorenko, D. N., 2021, Notes on the genera Aristopus, Cosmodiscus and Metabacetus (Coleoptera: Carabidae: Pterostichini: Abacetina), with description of three new species from Vietnam, Russian Entomological Journal 30 (4), pp. 413-429 : 419-421

Aristopus LaFerté-Sénectère, 1853

LaFerté-Sénectère, 1853: 373; Straneo, 1982: 338; 1983: 313; Will, 2020a: 165. — Celioschesis Tschitschérine, 1898: 93 (type species: Distrigus bipustulatus Brullé, 1834 , designated by Jeannel, 1948); Péringuey, 1926: 628; Straneo, 1940: 211; Jeannel, 1948: 442.

Type species: Aristopus trimaculatus LaFerté-Sénectère (by monotypy).

DIAGNOSIS. As for Metabacetus , except that the body is robust, reminiscent of Amara Bonelli, 1810 , subgenus Celia C. Zimmermann, 1832 , dark brown to black, mostly with pale elytral pattern, mandibles shorter and more incurved, eyes nearly hemispherical, labial pits missing, tibiae, especially mesotibia, more strongly armed with spiniform setae, metatibia with 2–4 spiniform setae (vs. glabrous) along outer margin, basal bead distinct outside basal sulci (vs. totally obliterate), elytral discal pore d2 present in most species. Abdominal sternite VII with medial setae distant far from apical margin in both sexes and thence arranged into a transverse row in female. — See also ‘Comments’ below.

REDESCRIPTION. Body ( Figs 19–20 ) convex, black or dark brown, often iridescent due to the presence of a very superficial microsculpture consisting of very transverse meshes or very dense transverse lines; body appendages, more or less wide pronotal margins, reflexed lateral margins of elytra, and maculate elytral pattern red or reddish-yellow.

Dorsal setation complete, except that elytral discal setae are reduced to d2 or (three species from Indochina) totally, combined with parascutellar seta lost in the latter case.

Head medium-sized, without neck constriction behind eyes; these large, convex, almost hemispherical, nearly reaching maxillary grooves beneath; genae short, subtransverse, meeting neck at obtuse angle (vs. nearly right in Cosmodiscus ), anteroventrally without antennal grooves; frontal sulci mostly short, deep and divergent. Mandibles normal in shape, i.e., moderately long, distinctly incurved in apical half, with dorsolateral margin rounded at least medially. Apical maxillary and labial palpomere fusiform, penultimate labial palpomere bisetose. Mentum with a distinct median tooth varying between species in shape.

Pronotum quadrate to obtrapezoidal; sides rounded, entirely beaded; disc convex; lateral margin mostly explanate and reflexed, becoming increasingly wide toward base. Base truncate or laterally oblique, beaded outside basal sulci; basal angles obtuse, not or minutely toothed. Apex truncate or subsinuate, with apical angles slightly projecting; apical bead entire to totally obliterate. Basal sulci deep, parallel or converging apicad, running on about basal third. Basal sulci at bottom and sides more or less distinctly punctate.

Elytra rather wide, with humeri and preapical sinuation distinct, sides rounded to subparallel. Basal ridge entire, humeral angle obtuse. Striae entire, deep, impunctate, stria 7 separately reaching apex, stria 8 starting from basal ridge or humerus. Intervals 8 and 9 subequally wide except basally, USS consisting of 14 US, with patterns 6–1–7, 6–1–7 and 7– 7 being observed due to intermediate seta varying between specimens of one species in position. Parascutellar seta at base of stria 2. Stria 7 with two distinct setae at apex.

Legs rather strong, protibia apically more or less dilated, with three lateroapical spines, these equidistant inter se or apical two proximate. Mesotibia with strong spiniform setae, 4–5 anterolateral and one posterolateral near distal anterolateral seta; inner setal brush consists of 8–12 setae becoming increasingly short and curved basad, with distal seta being longest and more or less separated from the others. Metatibia with 2–4 strong outer setae. Meso- and metatarsomeres 1–3 with more or less distinct lateral setae just above ventral setae; meso- and metatarsomere 1 or metatarsomeres 1 and 2 with outer (anterior) dorsolateral sulcus. Tarsomere 5 with dorsal (dorsolateral) seta preapical in position; tarsomeres 1 and 2 with DAS subequally developed in all tarsi; tarsomere 4 with ventro-apical setae simple (not lamellate). Protarsomeres 1–3 dilated and biserially squamose in male, those 1 and 2 toothed at latero-apical angles in female.

Aedeagus ( Figs 38–41 , 50–51, 56–59 ): median lobe arcuate, with a longitudinal ventromedial carina in the curve and apex slightly upturned in lateral view. Internal sac with a few, more or less distinct, sclerotized folds.

Abdominal urite VIII in female as in Figs 27–36. Female genitalia and reproductive tract (Figs 31, 36–37): Urite IX with ventral membrane setulose, laterotergite apically round- ed, setulose; gonosubcoxite glabrous ( A. bipustulatus , A. picturatus ) or with three small and dense lateroapical setae ( A. humeratus sp.n.), gonocoxite triangular, with double preapical nematiform seta, a very strong ventral ensiform seta and no dorsal setae, sometimes (single specimen of A. humeratus sp.n.) with 2–3 ventral ensiform setae (Fig. 36); bursa copulatrix membranous, spermatheca long convoluted.

GEOGRAPHIC DISTRIBUTION. Widespread in the Paleotropical realm, including Afrotropical, Madagascan and Oriental ( India to Indochina) regions.

HABITATS AND HABITS. No data, except that most specimens of two species reviewed here have been collected at light.

COMMENTS. According to Straneo [1983], the genus includes 20 Afrotropical and three Madagascan species.

In interpreting this genus, authors allowed some faults to occur. Firstly, Andrewes [1920] described a new species within the formerly monobasic Australian genus Cosmodiscus , while making no comparison between it and any representative of similar African (and Madagascan) genera Aristopus or Celioschesis . He did not accidentally described the elytral setation for Cosmodiscus and found no grounds to differentiate between Cosmodiscus platynotus and the other two species reviewed. Just after, Andrewes [1921] rectified his omission by stressing the point that C. picturatus Andrewes, 1920 had the median elytral discal seta (d2) and the congeners had no discal setae at all, while passing a side remark on an undescribed species of Cosmodiscus from South Africa. Later, the names Aristopus LaFerté-Sénectère, 1853 and Celioschesis Tschitschérine, 1898 were recognized as congeneric [ Straneo, 1982], and Cosmodiscus Sloane, 1907 has recently been mentioned as the next probable synonym [ Will, 2020a].

In spite of the Andrewes’ note about the seta d2 [ Andrewes, 1921] Straneo [1940] only distinguished between Cosmodiscus and Celioschesis by the elytra without discal setae or with d2, respectively. He [ Straneo, 1940] otherwise recognized the two genera as close relatives defined by the ‘normal’ aedeagus (vs. inversed in Drimostomatina , as Caelostomini), combined with the elytral parascutellar striole missing, parascutellar seta at base of stria 2, and USS being continuous. Then Straneo [1951] erected the genus Celioinkosa for Celioschesis kivuana Burgeon, 1935 , based chiefly on its distinctive mandibles, dorsally depressed and obliquely striated, combined with the body Amara -like following the subequally wide pronotal and elytral bases, and also the pronotal lateral margin widely explanate and reflexed, elytral d2 missing, the apical labial palpomere fusiform, and the prosternal process not beaded. Later [ Straneo, 1995], he reported that this character combination defined also the genera Inkosa Péringuey, 1926 and Oodinkosa Straneo, 1951 , and discriminated between the three genera by the apical labial palpomere peculiar in shape, subtriangular in Oodinkosa , subparallel-sided in Inkosa , and oval in Celioinkosa , in couple with slight differences between the aedeagi of Inkosa and Oodinkosa on one hand, and that of Celioinkosa , on the other. Surprisingly, this author never compared all these taxa or at least C. kivuana with Cosmodiscus platynotus or C. louwerensi Straneo, 1940 , even though no generic differences as above could be found between these three.

The characters discussed were also used in the key for identification of the Central African abacetine genera [ Straneo, 1982], which did not cover Afrotropical or Madagascan genera distributed beyond this region: Inkosa , Cyrtomoscelis Chaudoir, 1874 , and Pioprosopus Tschitschérine, 1899 . This latter [ Tschitschérine, 1899; 1902] seems to be very similar to Inkosa , Oodinkosa , and especially to Celioinkosa , except

35 36 37

Figs 25–37. Abdominal urites VIII and IX in female: 25–26, 34 — Metabacetus hermanni ; 27–28, 37 — Aristopus bipustulatus ; 29–30, 36 — A. humeratus sp.n.; 31 — Aristopus basilewskyi , urite IX and reproductiv tract; 32–33, 35 — Cosmodiscus platynotus ; 25, 27, 29, 32 — tergite VIII; 26, 28, 30, 33 — sternite VIII; 34, 35–37 — urite IX in ventral view; bc — bursa copulatrix; ltp — process of laterotergite; ov — common oviduct; sg — spermathecal gland; sp — spermatheca. Scale bars: 1 mm.

Рис. 25–37. Уриты VIII и IX брюшка самки: 25–26, 34 — Metabacetus hermanni ; 27–28, 37 — Aristopus bipustulatus ; 29–30, 36 — A. humeratus sp.n.; 31 — Aristopus basilewskyi , урит IX и репродуктивный тракт; 32–33, 35 — Cosmodiscus platynotus ; 25, 27, 29, 32 — тергит VIII; 26, 28, 30, 33 — стернит VIII; 31, 34, 35–37 — урит IX вентрально; bc — копулЯтивнаЯ сумка; ltp — вырост латеротергита; ov — непарный Яйцевод; sg — ЖелеЗа сперматеки; sp — сперматека. Масштаб: 1 мм.

only that it has short metepisternum and the neck constriction which is more or less traceable behind the eyes.

My comparison between Celioinkosa mirei Straneo, 1995 ( Fig. 70 ), three species of Aristopus , one African ( A. basilewskyi Straneo, 1948 ) and two Madagascan ( A. bipustulatus Brullé, 1834 , the type species of Celioschesis , and A. mocquerysi Jeannel, 1948 ), and most species of ‘ Cosmodiscus ’ ( Figs 19–24 , 68–69 ) has revealed, firstly, that some significant characters vary between these species considerably, so that both the elytral parascutellar seta and d2 may be present or not. Secondly, the combination of the following five characters (n 0 /n 1, plesiotypic/apotypic state; na / nb, unordered) serve good for arranging all the species into two groups (for additional differences see the key below):

1) Mandibles normal in shape, elongated, slightly incurved, with dorsal side slightly flattened inside a more or less rounded dorsolateral edge (10). — Vs. mandibles as described for Celioinkosa , i.e., shorter, wider and more incurved, dorsally depressed just inside a carinate dorsolateral edge (11);

2) Abdominal sternite IV either with (20) or without (21) paramedian obligatory setae;

3) Pronotal apical bead either entire (30) or obliterate medially to totally (31);

4) USS posterior group contains either seven (4 a) or eight (4 b) setae, respectively;

5) Pronotal basal bead either laterally distinct (50) or totally obliterate (51).

The first group includes species of Aristopus , ‘ Cosmodiscus ’ picturatus and an undescribed species; all of them are defined by the combination 1020314a 50 and have smaller eyes. Based on the evidence the two species of ‘ Cosmodiscus ’ are here either transferred to ( C. picturatus ) or described below within Aristopus , and the fact that the parascutellar seta and seta d2 are absent from the elytra of A. humeratus sp.n. restricts character combination to discriminate Aristopus from Cosmodiscus or other genera. Because A. humeratus sp.n. is very similar to Drimostoma kaszabi Jedlička, 1954 , in many characters, including colour pattern of the elytra, parascutellar and discal setae missing, and the pronotum with apical bead interrupted in the middle, the latter species is here provisionally placed within Aristopus . Just the same is true of C. latus Andrewes, 1947 , even though Andrewes [1947] said nothing about parascutellar seta in the description while noted great similarity between C. latus and C. umeralis Andrewes, 1937 , a true member of Cosmodiscus .

The remaining species of Cosmodiscus share character combination 1121304b 51 (or at least 1130 because the other characters remain not examined across Inkosa , Oodinkosa , Celioinkosa and Aristopus ) which invites synonymy Cosmodiscus Sloane, 1907 = Celioinkosa Straneo, 1951 , syn.n., whether Cosmodiscus and Aristopus are recognized as congeners elsewhere or not.

There are two defects in the scheme proposed: (1) some African species of Aristopus [ Straneo, 1983] have entire apical bead of the pronotum and (2) Oodinkosa leleupi Straneo, 1960 has the median lobe of aedeagus [ Straneo, 1995] more similar to that of Cosmodiscus . Aedeagi otherwise are more or less distinctive in the genera compared. Specifically, the median lobe in lateral view has the apex straight to slightly upturned, combined with ventral margin concave, in Aristopus , Inkosa and Oodinkosa , but curved ventrad in Cosmodiscus , ventral margin being concave in eastern ( Cosmodiscus s.str.) or bisinuate in western (= Celioinkosa ) species ( Figs 42–49 ).

It has also been found that the mentum and the submentum vary between the examined species of Aristopus considerably in shape, which may reflect species-specific differences. In particular, the submentum is deeply transversely impressed at its base, with the gular sutures impressed in form of small deep pits, in A. picturatus and A. humeratus sp.n. and slightly less so in A. bipustulatus . The mentum tooth is either large and apically rounded ( A. humeratus sp.n.) or smaller, apically truncate and subsinuate ( A. picturatus ), or still short- er, apically truncate and wide ( A. bipustulatus ), or large, very convex along middle, apically rounded yet subtruncate, i.e., with latero-apical angles somewhat traceable ( A. mocquerysi ). This latter species is distinctive also in having the ridge (that separates between the mentum and its tooth and then laterally extends into epilobes) submarginal, bead-like (vs. transverse in the other three species), combined with the submentum not transversely impressed.

Figures

Figs 19–24. Dorsal habitus: 19 — Aristopus picturatus, ♀ from Anuradhapura env., Sri Lanka; 20 — A. humeratus sp.n., paratype ♂ from env. Pai, Thailand; 21 — Cosmodiscus platynotus, ♀ from the Bi Doup — Nui Ba Nature Reserve; 22 — C. rufoapicalis sp.n., holotype; 23 — C. rufolimbatus, holotype; 24 — C. louwerensi, paratype. Рис. 19–24. Габитус дорЗально: 19 — Aristopus picturatus, ♀ иЗ окр. Анурадхапура, Шри Ланка; 20 — A. humeratus sp.n., паратип ♂ иЗ окр. Паи, Таиланд; 21 — Cosmodiscus platynotus, ♀ иЗ Запов. Бидуп-Нуйба; 22 — C. rufoapicalis sp.n., голотип; 23 — C. rufolimbatus, голотип; 24 — C. louwerensi, паратип.

Figs 38–49. Median lobe of aedeagus: 38–39 — Aristopus humeratus sp.n., paratype ♂ from env. Pai, Thailand; 40–41 — A. picturatus, ♂ from Vilpattu, Sri Lanka; 42–43 — Cosmodiscus platynotus; 44–45 — C. rufoapicalis sp.n., holotype; 46–47 — C. louwerensi, paratype; 48–49 — C. mirei; 38, 40, 42, 44, 46, 48 — left aspect; 39, 41, 43, 45, 47, 49 — right aspect; vc — ventral longitudinal carina. Scale bars: 1 mm. Рис. 38–49. СреднЯЯ долЯ Эдеагуса: 38–39 — Aristopus humeratus sp.n., паратип ♂ иЗ окр. Паи, Таиланд; 40–41 — A. picturatus, ♂ иЗ Вильпатту, Шри Ланка; 42–43 — Cosmodiscus platynotus; 44–45 — C. rufoapicalis sp.n., голотип; 46–47 — C. louwerensi, паратип; 48–49 — C. mirei; 38, 40, 42, 44, 46, 48 — слева; 39, 41, 43, 45, 47, 49 — справа; vc — продольный вентральный киль. Масштаб: 1 мм.

Figs 50–67. Aedeagus: 50, 56–57 — Aristopus humeratus sp.n., paratype ♂ from env. Pai, Thailand; 51, 58–59 — A. picturatus, ♂ from Vilpattu, Sri Lanka; 52, 60–61 — Cosmodiscus platynotus; 53, 64–65 — C. rufoapicalis sp.n., holotype; 54, 62–63 — C. louwerensi, paratype; 55, 66–67 — C. mirei; 50–55 — median lobe, ventral aspect; 56, 58, 60, 62, 64, 66 — right paramere, left aspect; 57, 59, 61, 63, 65, 67 — left paramere, right aspect. Scale bar: 1 mm. Рис. 50–67. Эдеагус: 50, 56–57 — Aristopus humeratus sp.n., паратип ♂ иЗ окр. Паи, Таиланд; 51, 58–59 — A. picturatus, ♂ иЗ Вильпатту, Шри Ланка; 52, 60–61 — Cosmodiscus platynotus; 53, 64–65 — C. rufoapicalis sp.n., голотип; 54, 62–63 — C. louwerensi, паратип; 55, 66–67 — C. mirei; 50–55 — среднЯЯ долЯ вентрально; 56, 58, 60, 62, 64, 66 — праваЯ парамера слева; 57, 59, 61, 63, 65, 67 — леваЯ парамера справа. Масштаб: 1 мм.

Figs 68–70. Dorsal habitus of Cosmodiscus spp.: 68 — C. sharovae sp.n., holotype; 69 — C. umeralis, holotype; 70 — C. mirei, paratype ♂. Рис. 68–70. Габитус дорЗально Cosmodiscus spp.: 68 — C. sharovae sp.n., голотип; 69 — C. umeralis, голотип; 70 — C. mirei, паратип ♂.