Rismethus rainoni, Platia & Coache, 2023

Platia, Giuseppe & Coache, Alain, 2023, Description of a new species of Rismethus Fleutiaux, 1947 from Republic of Benin with a key to the known African species (Coleoptera, Elateridae, Agrypnini), Faunitaxys 11 (27), pp. 1-4 : 1-2

Rismethus rainoni n. sp.

( Fig. 1-7 )

ZooBank : http://zoobank.org/ 4BB67393-55C9-4DDF-A2EB-11CB4FBD5F27

Holotype, ♂, Bénin, Athiémé, rives du Mono , 20.XI.2022, 06°14’20’’N - 01°40’00’’E - 29 m ( Fig. 6 & 7 ), A. Coache leg. ( CCEC) .

Paratypes (24 ex.)

- 8 ♂ & 9 ♀, same data as holotype ( CCEC, CAC, CPG) .

- 1 ex., Bénin, Dan, rives du Zou , 17 V 2013, ultra violet, 07°26'32''N - 02°11'57''E, 52 m, A. Coache leg. ( CAC) .

- 1 ex., Bénin, Pénéssoulou, Gatakpal , 23 II 2020, ultra violet, 09°14'57.00N - 01°35'55.86''E, 374 m, B. Rainon leg. ( CBR) .

- 1 ex., Bénin, Pénéssoulou , sortie du village, zone humide, ultra violet, 21 II 2020, 09°14'47.29''N - 01°33'00.65''E, 386 m, A. Coache leg. ( CAC) .

- 1 ex., Bénin, Pénéssoulou, forêt de Pénélan , 06 X 2019, ultra violet, 09°14’58.59’’N - 01°31’34.32’’E, 401 m, A. Coache leg. ( CAC) .

- 1 ♂ & 1 ♀, Pénéssoulou , stade, 18 X 2012, ultra violet, 09°14’15’’N - 01°33’12’’E, 415 m, A. Coache leg. ( CLD) .

- 1 ♀, Pénéssoulou, forêt de Pénélan , 11 X 2012, ultra violet, 09°14’50’’N - 01°31’45’’E, 392 m, A. Coache leg. ( CLD) .

Diagnosis. – A species close to R. riesei Platia, Biondi & Sechi, 2020 from Gabon that can be separated for the smaller size and the stouter body because of shorter elytra compared to pronotum and aedeagus with slenderer median lobe and apices of paramera.

Description of the holotype

Coloration. – Not or moderately shiny; entirely dark-brown generally with reddish shadings on the basal slope, after the middle and at apex of elytra, in some specimens simulating two symmetrical, sub-rounded spots after the middle near the suture; antennae and legs lighter, ferruginous; all the body is clothed with regular, short, thickened and dark- yellowish scales, partially hiding the integuments.

Head. – Narrower than the anterior margin of pronotum, frons slightly convex, densely punctured, with a rough surface, anterior margin straight, prolonged andmergedwiththeclypeus. – Antennae ( Fig. 2 ) very short, strongly serrated from the fourth article on; second and third articles sub-cylindrical, with the second of a larger diameter and slightly longer than the third, taken together twice longer than the fourth; fourth-tenth dilated and wider than long, the last longer and after the middle asymmetrically constricted to the apex.

Thorax. – Pronotum 1.09-1.12x wider than long, widest in the anterior third, convex, gradually sloping at the sides, more abruptly at base, with a short and shallow mid-longitudinal depression on the basal slope; sides moderately dilated in the anterior third, suddenly constricted before the apex and prolonged to include the eyes; backwards gradually tapering and very slightly sinuate before the posterior angles, the latter short, scarcely divergent, widely truncate and with a very light carina difficult to see; lateral margins crenulate, visible in a dorsal view and interrupted just before the anterior constriction; punctuation dense, uniformly distributed; punctures deep, simple, with shortest and shiny interstices difficult to see because hidden by the scales. – Pronoto-sternal sutures deeply grooved in the first half to receive theantennae. Deep grooves subparallel to the pronoto-sternal sutures are present for the accomodation of the anterior tarsi.

Scutellum. – Longer than wide, convex, longitudinally carinate, uniformly, finely and densely punctured.

Elytra. – 1.9x longer than pronotum and as wide as it, 1.66x longer than wide, convex; sides clearly arcuate, widest just before at the middle then regularly tapering to the apices, these rounded; surface hidden by the scales but shiny, strongly punctured with not well defined striae and interstriae. – Wings well developed and able to the fly.

Legs. –Tarsalarticlessimpleanddecreasingregularlyinlength;clawssimple.

Aedeagus ( Fig. 1 ). – With median lobe just a little longer than the paramera (length 0.37 mm).

Female. – Extremely similar to the male only with a little large body and impossible to separate without examination of the genitalia.

Size. – length 2.3-2.9 mm; width 0.85-1.0 mm.

Etymology. – The species is dedicated to our friend and traveling companion,Mr. Bernard Rainon with whom we have been inventorying the entomological fauna of Benin for more than 15 years now.

Ecological notes. – We cannot specify the ecology of this new species because all the specimens were captured during night hunting with ultraviolet light along the Mono River which borders Benin and Togo, in the municipality of Athiémé.

Figures

Fig. 1-5. Rismethus rainoni n. sp. 1. Aedeagus, dorsal view. 2. Antenna. 3-5. Habitus. 3. Dorsal. 4. Ventral. 5. Lateral.

Fig. 6. Biotop of the holotype of Rismethus rainoni n. sp.

Fig. 7. Method of collecting the holotype of Rismethus rainoni n. sp.