Arsinoe aguiari, 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 : 371-372

Arsinoe aguiari sp. n.

( Figures 1a , 2a–b )

Type series. Holotype male: “Coli (Quebo) Tombali \ Guiné-Bissau 17.07.2006 \ Col. A. Serrano\\ A. Serrano leg.” \\ “Holotype male\ Arsinoe \ aguiari n. sp. \ A. Serrano det. 2023” [t] [h] [red card]; Paratype female: “Coli (Quebo) Tombali \ Guiné-Bissau 17.07.2006 \ Col. A. Serrano\\ A. Serrano leg.” \\ “Paratype female\ Arsinoe \ aguiari n. sp. \ A. Serrano det. 2023” [t] [h] [red card].

Differential diagnosis: Head, disc of the pronotum and elytra are black; the pronotum sides, antennae, mandibles (part), palps and tarsi are reddish-brown; femurs and tibiae dark red-brown; each elytron with two yellowish sub-rounded spots, one subhumeral and the other subapical, not divided from the contralateral one by the suture; head punctured, dorsal surface with strong longitudinal furrows in the lateral sides above the eyes and in the disc of frons; lateral margin of pronotum very large, punctured and distinctly and transversally furrowed; distinctive shape of aedeagus ( Figs 2a–b ).

Description

Length of the holotype: 9.4 mm.

Head ( Fig. 1a ). Much wider as long (male: length 1.52 mm, width: 2.14 mm; female: length 1.55 mm, width: 2.32 mm), scarcely punctured and glabrous, without microsculpture, strong longitudinal furrows on the sides above the eyes, lesser but visible on frons, vertex sparsely punctured, decreasing to rear; mandibles of medium length; labrum wider than long (male: length 0.21 mm, width: 0.64 mm; female: length 0.27 mm; width: 0.67 mm), lightly punctured, anterior margin slightly arcuate, six submarginal setae along the anterior edge; clypeus sparsely but distinctly punctured, anterior margin slightly arcuate, one long and fine brown-yellowish seta in the middle of each side near lateral, posterior margin convex; mentum largely triangular, glossa with two setae at apex, paraglossae longer than the glossa, pubescent on the external side; palps microreticulate, the labial dichetes, last palpomeres trunk, not dilated apically; eyes large and prominent, temples short, narrowing obliquely towards the neck; antennae short, not surpassing posteriorly the base of the elytra, 1 st antennomere twice longer than the 2 nd, the 3 rd and the 4 th are the same length, but almost twice longer than the 2 nd, 4 th antennomere pubescent from the distal half and slightly longer than the 5 th antennomere, the remaining ones with pubescence, decreasing very gradually to the penultimate, the last antennomere longer and more or less acuminate; one pair of supraorbital long ferruginous setae on each side.

Thorax. Pronotum strongly transverse ( Fig. 1a ), 1.8–1.9 times as long as wide (male: length 1.76 mm, width: 3.17 mm; female: length 1.86 mm, width: 3.44 mm), widest point just before the middle; anterior margin arcuate, slightly narrower than the base, lateral margins moderately rounded anteriorly, narrowed posteriorly, very slightly sinuated just anterior to the posterior angles; anterior angles rounded, slightly protruded; posterior angles obtuse, sharped at apex, protruding outwards; margins ridged all-around, including the middle of the posterior margin which is slightly emarginated; surface of disc smooth among the moderately dense small and medium punctures; 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 transverse sulcus very faintly distinct, masked with small longitudinal grooves; posterior transverse sulcus not clearly visible; lateral surface between disc and lateral margins very large, strongly arched and raised, deepened posteriad, stronger punctuation than the discal one, forming oblique irregular meshes, stronger in the posteriad half; scutellum triangular, scarcely punctured.

Elytra ( Fig. 1a ) subparallel-sided, 1.3 times as long as wide (male: length 6.14 mm, width: 4.82 mm; female: length 6.67 mm, width: 5.28 mm), widening slightly towards the posterior third; each elytron with two yellowish sub-rounded spots, one subhumeral, extending from the 3 rd to the 8 th interval and the other subapical, extending from the 1 st to the 4 th interval; the first seven striae visible, well-marked, finely punctured, reaching the base, outer 8 th and 9 th striae less marked, incomplete; scutellar striae scarcely punctured, well visible between suture and 1 st striae; each elytron ridged all-around from the sutural apex to the scutellum, not toothed in the shoulders, forming a curve; apical margin not sinuous; interval surfaces shiny, glabrous, moderately convex, distinctly punctured, smooth among punctures; setiferous basal pore present; two setiferous discal pores on the 3 rd interval; umbilicate series constituted by 14 setiferous pores (6 aggregate behind the shoulders, 3 central and 5 subapical); two apical setae, one of which inserted in a smaller umbilical pore;

Ventral surface. Head underside, lateral surfaces of pro-, meso- and metasternum and metepisterna blackish, pronotum lateral underside, central surfaces of pro-, meso- and metasternum and abdomen brownish or dark brownish, silky; gula and ventral and lateral sides of genae (neck) smooth, glabrous; prosternum and propleura scarcely punctured, each puncture with an erected minute seta, mesosternum punctured in the middle, meshed in the lateral declivities, metasternum smooth in the middle, gradually punctured in the lateral surfaces; metepisterna elongated, narrowed posteriorly and punctured; prosternal apophysis not bordered; elytral epipleura simple, enlarged and excavated longitudinally in the first third, narrowing roughly to the apex; abdomen surface very finely punctured, not microreticulate; last abdominal sternite with two pairs of submarginal setae (male and female).

Legs ( Fig. 1a ) slightly elongated; male first four fore tarsomeres slightly dilated, underside felted with two rows of squamulose setae; first four tarsomeres of intermedium and hind tarsi pubescent underneath; female first four tarsomeres pubescent underneath, the first four fore not dilated in female; tarsomere 4 th not bilobed; onychium only with lateral setae underneath (male and female); claws simple.

Male genitalia ( Figs 2a–b ). Median lobe medium sized (length: 2.1 mm), stout, the anterior and middle regions largely bossed in the right side (dorsal view); ostium large, membranous, displaced to the right side; apical lamella short, rounded (dorsal view), acuminate (lateral view) at apex; basal bulb developed, slightly bossed in the right side; ventral margin strongly bossed in the middle, apex bending very slightly downwards (lateral view) ( Fig. 2a ); endophalus with a very diffuse small sclerite in the left side of the first third (dorsal view); left paramere large, rounded, longer than wide, without any distal tooth ( Fig. 2a ).

Etymology. This species is named in honour of Dr. Carlos Aguiar (Lisboa, Portugal) a friend and well-known specialist of Carabidae , who has collaborated with the author for more than 30 years in the study of the ground beetles of Portugal.

Distribution. Only known from Guinea-Bissau.

Remarks. Considering the general shape and some external morphological characters (e.g., general colour, yellowish elytral spots pattern, lack of microreticulation) Arsinoe aguiari n. sp. seems to be close to Arsinoe flavosignata (Gory, 1833) and Arsinoe rugiceps Facchini, 2017 . The new species is also more akin with the later species by the blackish femurs (yellowish in the former species), the head with strong longitudinal ridges on the sides near and above the eyes (these ridges are barely visible in A. flavosignata ) and the very wide lateral sides of the pronotum (not so wide in A. flavosignata ). However, some other external characters allow separating these two species from A. aguiari n. sp. Arsinoe rugiceps presents the surface of frons punctured (not or very slightly in the new species), the lateral margin of pronotum more rounded in the middle and the apical margin of elytra slightly sinuate (not in the new species) (see Fig. 1a and Fig. 2 in Facchini 2017). Regarding A. flavosignata , in addition to the differences already indicated above, it also differs from the new species by a smaller length, the 2 nd, 3 rd and 4 th antennomeres black (reddish in the new species), the lateral margin of pronotum not sinuated just anterior to the posterior angles (very slightly sinuated in the new species), the pronotal surface less punctured and without lateral oblique ridges (stronger punctured and with lateral oblique ridges in the new species, the elytral surface among striae scarcely punctured (stronger punctured in the new species), elytral spots more reduced than in the new species and a different shape of median lobe of aedeagus.

The new species differs from the remaining African species by the median lobe shape, among other external morphological characters.

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).