Dontolobus bivari, Serrano, 2024

Serrano, Artur R. M., 2024, Ground beetles of the subfamily Lebiinae (Carabidae) of Guinea-Bissau: description of three new species and faunistic notes, Zootaxa 5419 (3), pp. 361-393 : 374-376

Dontolobus bivari n. sp.

( Figures 1b , 2c–d )

Type material. Holotype male: “ Quebo (Coli)\ 28.06.1995 \ Col. A. Serrano ”\\ “A. Serrano leg.” \\ “Miss. Ent. SPEN \ à Guiné-Bissau \ 25 Junho a 17 Julho 95” \\ “Holotype male\ Dontolobus \ bivari n. sp. \ A. Serrano det. 2023 [t] [h] [red card]. Paratypes: “ Quebo (Coli)\ 28.06.1995 \ Col. A. Serrano ”\\ “A. Serrano leg.” \\ “Miss. Ent. SPEN \ à Guiné-Bissau \ 25 Junho a 17 Julho 95” \\ “paratype female\ Dontolobus \ bivari n. sp. \ A. Serrano det. 2023 [t] [h] [red card]; “ Quebo (Coli)\ 03.07.1995 \ Col. A. Serrano ”\\ “A. Serrano leg.” \\ “Miss. Ent. SPEN \ à Guiné-Bissau \ 25 Junho a 17 Julho 95” \\ “ Paratype male\ Dontolobus \ bivari n. sp. \ A. Serrano det. 2023” [t] [h] [red card]; “ Quebo (Coli)\ 03.07.1995 \ Col. A. Serrano ”\\ “A. Serrano leg.” \\ “Miss. Ent. SPEN \ à GuinéBissau\ 25 Junho a 17 Julho 95” \\ “ Paratype female \ Dontolobus \ bivari n. sp. \ A. Serrano det. 2023” [t] [h] [red card]; “ Banhinda ( PNT Cacheu) \ Guiné-Bissau 27.6.2009 \ Col. A. Serrano” \\ “ A. Serrano leg.” \\“ Paratype female \ Dontolobus \ bivari n. sp. \ A. Serrano det. 2023” [t] [h] [red card].

Differential diagnosis: head, including mandibles, labrum, palps, antennae and legs reddish-brown; pronotum darker, elytra brown-blackish with yellow-reddish lateral margin, each elytron with a yellowish oblique subhumeral spot that reaches the base and a yellowish subapical spot on intervals 1 st –4 th; body glabrous, winged; head distinctly punctured; pronotum transverse, denser and finely punctured on the disc, lateral margins narrowing posteriad in a straight line up to the posterior angles; male genitalia ( Figs 2c–d ).

Description

Length of the holotype: 7.0 mm.

Head ( Fig. 1b ). Wider as long (males: length 1.52 mm, width: 1.70–1.79 mm; females: length 1.28-1.38 mm, width: 1.68-1.79 mm), distinctly punctured and glabrous, without microsculpture, slight longitudinal furrows on the sides near the eyes, not visible in frons, vertex punctured; mandibles of medium length; labrum wider than long (males: length 0.26–0.27 mm, width: 0.53–0.54 mm; females: length 0.24–0.27 mm; width: 0.51–0.54 mm), very slightly finely punctured, anterior margin just distinctly arcuate in the middle, six setae close to the anterior margin; clypeus slightly bossed longitudinally, sparsely but distinctly punctured in the middle, anterior margin straight, one long and fine anteriad brownish seta near lateral margin, posterior margin slightly convex; mentum largely triangular, glossa with two setae at apex, as well as two minute central setae very close between, paraglossae longer than the glossa, pubescent on the external side; palps microreticulate, with a few very small scattered setae, last palpomeres moderately narrowed towards the apex, labial palps dichete; eyes large and prominent, temples short, narrowing obliquely towards the neck; antennae short, not surpassing posteriorly the base of the pronotum, 1 st antennomere twice longer than the 2 nd, the 3 rd and the 4 th with the same length, but almost twice longer than the 2 nd, 4 th antennomere pubescent from the distal half and with the same length of 5 th antennomere, the remaining ones pubescence, with the same length, the last antennomere longer and more or less acuminate; one pair of supraorbital long dark ferruginous setae on each side.

Thorax. Pronotum strongly transverse ( Fig. 1b ), 1.8–1.9 times as long as wide (males: length 1.33–1.38 mm, width: 2.43–2.50 mm; females: length 1.31–1.39 mm, width: 2.43–2.56 mm), widest point clearly before the middle; anterior margin arcuate, slightly narrower than the base, lateral margins angulate at the maximum width, narrowed posteriorly almost in a straight line up to the posterior angles; anterior angles rounded, slightly protruded; posterior angles strongly obtuse, not sharped at apex; posterior margin finely ridged, slightly emarginated, not lobed in the middle; surface of disc with transverse microreticulation among denser and smaller punctures than the head; two setae in each lateral margin, one at the maximum width and one at the posterior angle; longitudinal median sulcus fine, clearly visible in the median part, not reaching the anterior and posterior margins; anterior and posterior transverse sulci very faintly distinct, not clearly visible; lateral surface between disc and lateral margins very large, widened posteriad, with isodiametric reticulation, coarser punctuation than that of the disc; scutellum triangular, with isodiametric reticulation, scarcely punctured.

Elytra ( Fig. 1b ) short, 1.2–1.3 times as long as wide (males: length 4.42–4.49 mm, width: 3.52–3.55 mm; females: length 4.22–4.42 mm, width: 3.42–3.58 mm), maximum width approximately in the middle; each elytron with a yellowish oblique subhumeral spot extending from the 3 rd –7 th intervals, reaching the base in the 5 th –7 th intervals and a yellowish subapical spot, extending from the 1 st –4 th intervals; eight striae visible, shallow, finely punctured, reaching the base, outer 8 th less marked anteriad; scutellar stria scarcely punctured, well visible between suture and 1 st stria; each elytron ridged all-around from the scutellum to the ending of the 2 nd stria just before the sutural apex, not toothed in the shoulders, forming a curve; apical margin very slightly sinuous; interval surfaces silky, glabrous, not convex, finely but distinctly punctured, isodiametric microreticulation among punctures; setiferous basal pore present; two setiferous discal pores on the 3 rd interval, the anterior near 3 rd stria, the posterior near 2 nd stria; umbilicate series constituted by 14 setiferous pores (6 aggregate behind the shoulders, 2 central and 6 subapical); two apical setae, one of which inserted in a smaller umbilical pore.

Ventral surface. All underside brownish, glabrous; gula and mesosternum smooth; ventral and lateral sides of genae (neck), prosternum and propleura faintly and scarcely punctured, some punctures of prosternum with pale minute setae dressed and directed posteriad; metasternum smooth in the middle, gradually punctured in the lateral surfaces; metepisterna elongated, narrowed posteriorly, smooth; prosternal apophysis not bordered; elytral epipleura simple, enlarged and slightly excavated longitudinally in the first third, narrowing roughly to the apex; abdomen surface very scarcely and finely punctured, smooth among punctures, transverse microreticulation only visible in the last abdominal sternite at high magnification; last abdominal sternite of males and females with 2 pairs of subapical setae.

Legs ( Fig. 1b ) slightly elongated; male first three fore tarsomeres slightly dilated, underside felted with two rows of squamulose setae, mesotibiae on the internal side with subapical notch; female fore tarsomeres not dilated; male and female first tarsomere of intermedium and hind tarsi pubescent underneath, remaining tarsomeres including the onychium only with lateral setae underneath; claws simple.

Male genitalia ( Figs 2 c–d ). Median lobe of aedeagus medium sized (length: 2.0 mm), very slightly sinuous on the ventral side (lateral view), concave in the lateral side (dorsal view); ostium small, membranous, displaced to the left side; apical lamella short, rounded (dorsal and lateral views); apex bending very slightly upwards (lateral view) ( Fig. 2 c ); basal bulb thin; endophallus without visible sclerites; left paramere longer than wide, rounded at apex, slightly sinuous on the ventral side, without any distal tooth ( Fig. 2 c ).

Etymology. This species is named in honour of Dr. António Bivar de Sousa, a friend, a specialist on Dermaptera and Lepidoptera, who I have participated with on several entomological missions carried out in Guinea-Bissau.

Distribution. Only known from Guinea-Bissau.

Remarks. Dontolobus bivari n. sp. is easily segregated from Dontolobus pallidus ( Burgeon, 1937) , Dontolobus sachtlebeni (Basilewsky, 1942) and Dontolobus mirei Basilewsky, 1970 by the pronotal angular lateral margins, corresponding to the maximum width instead of the rounded lateral margins of those three species. Moreover, the elytra spots drawing of the new species and the other are completely different. Dontolobus setosanalis Basilewsky, 1970 has a pronotum like that of D. bivari n. sp., but is easily separated by the number of submarginal setae pairs in the last abdominal sternite (6–7 vs 2) and by the elytral spots (dented bands vs more or less rounded bands). Dontolobus bivari n. sp. can also be distinguishable from Dontolobus aemiliae Facchini, 2012 and Dontolobus trinotatus Facchini, 2012 for a distinctly more transverse and lighter coloured pronotum. The new species differs also from D. aemiliae by the lateral margins of the pronotum which are not sinuated towards the base and the posterior obtuse angle largely rounded (slightly sharp in the latter species). Moreover, the three species differ from the shape and features of median lobe of aedeagus (see Figs 2c–d and Figs 8, 9 in Facchini 2012). Dontolobus labroexcisus Facchini, 2017 is easily segregated from the new species by the bigger size, the darker colour of the head and pronotum and the anterior margin of labrum with small but distinct V-shaped median incision. Dontolobus similis Facchini, 2012 differs also from the new species by the darker colour of head and pronotum and the anterior margin of pronotum almost straight (distinctly arcuate in the new species). Moreover, these three species differ from the shape and features of median lobe of aedeagus also (see Figs 2 c–d and Figs 8, 10 in Facchini 2017). Finally, taking into account the general shape and some external morphological characters (e.g., general colour, yellowish elytral spots), D. bivari n. sp. seems to be close to Dontolobus ivorensis Facchini, 2012 . However, the head and pronotum punctuation, the shape of clypeus and features connected with the median lobe of aedeagus (cf. Figs 2 c–d and Fig. 9 in Facchini 2017), easily allow the separation of these two species.

Figures

FIGURE 1. Habitus of Lebiinae species. (a) Arsinoe aguiari n. sp. (dorsal view), holotype male, Coli (Quebo), TOB, ASC; (b) Dontolobus bivari n. sp. (dorsal view), holotype male, Coli (Quebo), TOB, ASC; (c) Lasiocera schwarzi n. sp. (dorsal view), female, Banhinda, CAC, ASC; (d) Lasiocera asmara (dorsal view) plus labels, paratype, Eritreia, MRAC; (e) Lasiocera mirei (dorsal view) plus labels, paratype, Cameroon, MRAC; (f) Lasiocera nitidula (dorsal view) plus labels, female, Central African Republic, MRAC.

FIGURE 2. Aedeagus of: Arsinoe aguiari n. sp. (a), median lobe and right paramere (lateral views) (b), median lobe (dorsal view); Dontolobus bivari n. sp. (c), median lobe and right paramere (lateral views) (d), median lobe (dorsal view).