Diomus chiriqui González & Větrovec, 2021

González, Guillermo & Větrovec, Jaroslav, 2021, New species and records of Neotropical ladybirds (Coleoptera: Coccinellidae), Revista Chilena de Entomología (Rev. Chil. Entomol.) 47 (2), pp. 331-374 : 354-355

Diomus chiriqui González & Větrovec , new species

( Figs. 6 a-6l)

Holotype ♂ “ Panamá, Chiriqui / La Fortuna. 7.9.2010 / Cont. Divide Trail 1 / Pavel leg. 1153m ”, “ N 08°47’06.7” W 082°12’51.2 ””, “ ♂ 2040” ( NMP).

Paratypes (total 15 specimens): PANAMÁ: 4 ♂ same data as holotype (2 NMP, 2 JVC) ; 1 ♂ and 3 ♀ “ Panamá, Chiriqui / La Fortuna. 16.9.2010 / Cont. Divide Trail # 2 / Pavel leg. 1099m ”, “ N 08°46’37.1” W 082°12’16.8 ”” ( JVC); 1 ♂ “ Panamá, Veraguas prov., / Santa Fé - CerroMariposa, 800- / 1170m, 08°30.375’N, 81°07.218’W, / 30.v.2015, individual collecting, / L. Sekerka & K. Štajerová ” ( NMP) ; 6 ♀♀ same data as holotype (4 NMP, 2 JVC) .

Diagnosis. Males of Diomus chiriqui n. sp. have a yellow head and thorax and black elytra ( Fig. 6a ), while the female is entirely black ( Fig. 6e ). This combination of colors is quite common in the genus, although most of the species that possess it have a narrow yellow or reddish border at the elytral apex. The male genitalia are the only sure character to identify this species. The species is characterized by the presence of two sclerotized areas (teeth) near the penis guide apex, and apex not strongly inclined to one side ( Fig. 6i ), penis with a short apical filament no more than 1/5 of the length of the penis tube, penis capsule with welldifferentiated arms ( Figs. 6 j-6k), characters that assign it to group “C” of Gordon (1999). They are complemented by the presence of a dorsal keel, absence of hairiness in the penis guide and absence of inner hairiness in the parameres ( Figs. 6 g-6h), a unique combination in the group. Also, the very divergent sides of the penis guide, which is more than twice as wide apically than at the base, does not occur in any other species of the genus.

Description. Color pattern ( Figs. 6 a-6d). Male with head entirely yellow, including antennae and mouthparts. Pronotum yellow. Scutellar shield black. Elytra black, including epipleuron. Ventral side black, except on the yellow head and prothorax, abdomen brown, ventrite 1 and anterior half of ventrite 2 black. Legs yellow, except brown coxa. Pubescence yellow white, translucent. Female entirely black. Morphology. Body oval, elytra with regularly curved sides, widest at middle ( Fig. 6a ). Frons about twice the width of an eye. Eyes oval, slightly longer than wide, eye canthus 1/3 the width of an eye. Clypeus with apical margin slightly convex ( Fig. 6c ). Antenna with eleven antennomeres, club weakly defined. Apical maxillary palpomere securiform. Prosternum Y-shaped, short. Abdominal postcoxal lines complete, extended to hind margin of ventrite, evenly rounded ( Fig. 6f ). Tarsus trimerous. Head punctures small, not very apparent, space between punctures about twice the diameter; pronotum punctures slightly larger than those on head, separated by a diameter on average; elytra punctures larger than the pronotum, separated by half a diameter on average; ventral side punctures small, on metaventrite separated by three times their diameter; abdomen punctures fine, scant in the middle part, densely punctured on the lateral 1/4 of the ventrites. Pubescence decumbent, dense, associated with punctures; head hairs very short, pronotal and elytral hairs larger than on head about 3/4 of length of scutellar shield; abdominal pubescence long and quite dense on the lateral borders of ventrites 2 to 5. Male terminalia. Apex of ventrite 5 wavy, slightly concave in the center. Apex of ventrite 6 similar to 5, with a slightly more pronounced notch ( Fig. 6f ). Tegmen little more than twice as long as wide, phallobase as long as wide, with rounded posterior border. Tegminal strut as long as tegmen. Penis guide asymmetric, 2 ½ times longer than wide, divergent sides somewhat concave from the base to 4/5 of the length, where it is more than twice as wide as the base, then rounded up to the apex where there is a nipple-shaped projection, on the right side the upper border has two large teeth on a membranous area; in lateral view the penis guide presents a dorsal keel at the base, then it tapers slightly into an acute triangle, somewhat sinuous near apex, inner side with membranous areas, without dorsal pubescence. Parameres exceed the penis guide by 1/5 of the length, paddle-shaped, they finish in a rounded apex, pubescence in the apical half at the borders and apex, exceeding the paramere in length, without pubescence in the inner area ( Figs. 6 g- 6i). Penis curved in a semicircle in the basal half, then slightly curved up to the apex, at 2/3 of the length it tapers considerably, very narrow sinuous apex, on the inner side some membranous projections before the apex; penis capsule with long inner arm, twice as long as wide, outer arm slightly displaced outwards, wide, rhomboid, outer margin with a wide concavity, accessory piece present, large ( Figs. 6 j-6k). Female terminalia. Apex of ventrite 5 convex, almost truncate at middle, ventrite 6 with rounded apex ( Fig. 6f ). Spermatheca in S-shape, with the side of the cornu of greater diameter, of constant width and rounded apex with a little nipple-shaped projection at apex, ramus with a short beak. Infundibulum large, oval, with sclerosed tubes at both ends, coxites transversely triangular ( Fig. 6l ).

Measurements (mm): TL 2.4-2.6; PL 0.7; PW 1.3; EL 1.8; EW 1.8; GD 1.1.

Geographic distribution. Panama, ChiriquÍ province.

Remarks. The genus Diomus Mulsant, 1850 has a worldwide distribution, but the vast majority of the species are concentrated in South America, with about 283 species ( Gordon 1999; González and Honour 2011; González 2015a, 2016) and Australia, with an estimated

150 species ( Pang & Ślipiński 2009, 2010). For this study, the new species was compared in their habitus and genitalia with the South, Central, North American and Caribbean species ( Gordon 1985, 1999; Vandenberg and Hanson 2019). Diomus chiriqui n. sp. presents the characters of the genus, including the descending incomplete postcoxal lines, the trimerous tarsi, the short antenna of eleven antennomeres and the apical maxillary palpomere securiform, as well as the asymmetric male penis guide and the somewhat transverse triangular coxites of the female.

Figures

Figures 6a-6x. a-l:Diomus chiriquin. sp.; a-d: habitusmale (dorsal, lateral, frontal, posterior); e: habitus female (dorsal); f: abdomen; g-h: tegmen; i: penis guide; j-k:penis and detail; l: female terminalia. m-x: Diomus panamensis n. sp.; m-p: habitus (dorsal, lateral, frontal, posterior); q: abdomen; r: ventrite 6; s-t: tegmen; u-v: penis guide; w-x: penis and detail. Scale bars in mm. / a-l:Diomus chiriqui sp. n.; a-d: habitus del macho (dorsal, lateral, frontal, posterior); e: habitus de la hembra (dorsal); f: abdomen; g-h: tegmen; i: guÍa del penis; j-k: penis y detalle; l: terminalia de la hembra. m-x:Diomus panamensis sp. n.; m-p: habitus (dorsal, lateral, frontal, posterior); q: abdomen; r: ventrito 6; s-t: tegmen; u-v: guÍa del penis guide; w-x: penis y detalle. Escalas en mm.