Macromalthinus orapuensis, Biffi & Constantin, 2018

Biffi, Gabriel & Constantin, Robert, 2018, A revision of Macromalthinus Pic, 1919 with description of six new species (Coleoptera: Cantharidae: Chauliognathinae), Papéis Avulsos de Zoologia (Pap. Avulsos Zool., S. Paulo) 58, pp. 1-22 : 9-11

publication ID	https://doi.org/ 10.11606/1807-0205/2018.58.58
publication LSID	lsid:zoobank.org:pub:97C262C2-6F02-4916-9533-43653FE5561F
persistent identifier	https://treatment.plazi.org/id/03821672-FFD6-1D4E-511F-FF31FE66FCEC
treatment provided by	Valdenar
scientific name	Macromalthinus orapuensis
status	sp. nov.

Treatment

Macromalthinus orapuensis sp. nov.

( Figs. 3 View Figures 1-6 , 9 View Figures 7-12 , 15 View Figures 13-18 , 21 View Figures 19-24 , 27 View Figures 25-30 , 33 View Figures 31-36 , 39 View Figures 37-42 , 45 View Figures 43-48 )

Type material: HOLOTYPE: ♂: FRENCH GUIANA. Roura, RN 2, PK 65 [national road 2 at km 65], [Rivière] Orapu , Crique Orfion, 04°29’46”N, 52°20’43”W, 01.X.2016, Malaise trap, P.H. Dalens & SEAG ( MNHN). ( Fig. 3 View Figures 1-6 ) GoogleMaps . PARATYPES (1 ♂, 6 ♀). FRENCH GUIANA. Roura, RN 2, PK 65, Orapu , Crique Orfion, 04°29’46”N, 52°20’43”W, 01.X.2016, Malaise trap, P.H. Dalens & SEAG (1 ♀ MNHN, 1 ♂, 1 ♀ CCo) GoogleMaps ; same locality, 17.IX.2016, Malaise trap, P.H. Dalens & SEAG (2 ♀ CCo) GoogleMaps ; Régina, 10 km W, Petite

Montagne Tortue, 04°19’N, 52°14’W, 09.VI.2010, Malaise trap, G. Lamarre (2 ♀ CCo).

Differential diagnosis: Pronotum with broad median brown strip from anterior to posterior margins, laterally bordered by one yellow strip each side from anterior to posterior angles; elytra entirely brown; males: fore femur with blunt tooth near apex, notched beyond the apical fourth; aedeagus with right prolongation of tegmen narrowed apically and markedly oblique, separated from left setiferous prolongation by a broad and straight notch; left setiferous prolongation elongate, slender, with few short apical setae; females: ventrite VII trapezoidal, distal margin projected, notched medially.

Males of M. orapuensis sp. nov. differ from M. maximiceps (Pic) in the narrower and less concave frons between the eyes, antennomeres IV-V not widened and the different aedeagus. Macromalthinus orapuensis sp. nov. is similar to M. guyanensis sp. nov. and differs from the latter in the different apical edge of the aedeagus. Females of M. orapuensis sp. nov. differ by the distal margin of ventrite VII projected at middle and with a pair of lobes at apex (slightly projected, nearly straight in M. guyanensis sp. nov. and concave in M. maximiceps ).

Description: Length: 7.7-8.9 mm. Colouration: Head black. Maxillary palpi yellow, last palpomere apically infuscate. Antennae brown, antennomeres I-II and base of III testaceous, apico-dorsally infuscate. Pronotum with a broad median brown strip from anterior to posterior margins, laterally bordered by yellow strip each side, from anterior to posterior angles. Scutellum and elytra brown. Legs bicolour, coxae and trochanters yellow, femora yellow dorsally, covered with elongate brown strip on distal half, tibiae and tarsi brownish. Abdomen black ( Fig. 3 View Figures 1-6 ). A male paratype has a lighter colour scheme, pronotum yellow with dark-brown patch anteriorly, legs mostly yellow. One female paratype from Petite Montagne Tortue has a darker colour pattern, with pronotum brown.

Male: Head 1.22 times wider than pronotum; temples elongate, tapering posteriorly; frons depressed between eyes. Eyes developed, convex, internal margins convergent anteriorly. Antennae thin, slender, first antennomere dilated, 3.2 times longer than broad, following not compressed. Pronotum ( Fig. 9 View Figures 7-12 ) 1.12 times wider than long; anterior margin arched, posterior margin rounded medially, sinuate near angles. Lateral margins straight, regularly narrowing anteriorly; margins thinly bordered, stronger near anterior and posterior angles; pronotal surface dull, not punctate, with a thin, whitish pubescence. Elytra short, thinly punctate, slightly wrinkled, covered with thin yellowish setae, obliquely bent backwards; sutures dehiscent from anterior third; apex lustrous, narrower, swollen dorsally. Fore femur ( Fig. 15 View Figures 13-18 ) with a blunt tooth near apex, notched beyond apical fourth. Abdominal tergites and sternites broadly sclerotized; tergite VIII apically emarginated, distal angles prominent, forming a short conical projection; tergite IX as long as wide, asymmetrical, longer on its right side; ventrite VII ( Fig. 21 View Figures 19-24 ) H-shaped, sides arched, with deep, wide membranous area anteriorly, and deep, wider posterior notch; ventrite VIII ( Fig. 27 View Figures 25-30 ) asymmetrical,elongate, strongly convex; short and strong transverse lateral ridge near left margin, long and strong longitudinal ridge along right margin; distal surface densely pubescent. Aedeagus ( Fig. 33 View Figures 31-36 ) with right prolongation of tegmen narrow apically and markedly oblique, separated by a broad and straight notch from left setiferous prolongation; left setiferous prolongation elongate, slender, with few short apical setae; right paramere broad at base, rounded at apex; left paramere flat, wider at base, apex rounded, partially covering dorsal surface of median lobe; median lobe wider basally, broadly membranous apically. Measurements of holotype: TL: 8.9; AL: 5.9; HW: 1.34; IOW: 0.52; IAW: 0.17; OL: 0.68; PL: 0.98; PW: 1.1; EL: 1.84; EW: 1.3.

Female: Length: 7.7-8.3 mm. Similar to light form of Macromalthinus guyanensis but elytra shorter. Ventrite VII ( Fig. 39 View Figures 37-42 ) trapezoidal, longer, distal margin projected medially and notched at apex forming two small lobes; stylus of coxites ( Fig. 45 View Figures 43-48 ) not constricted at base.

Etymology: The name refers to the locality (Orapu river) where the holotype was collected.

Distribution: French Guiana ( Figs. 66, 69 View Figures 66-69 ).

Locality description: The specimens were collected with malaise traps in peculiar natural zones of lowland swamp forests on hydromorphic soils at Crique Orfion and Petite Montagne Tortue. Both localities, southeastwards Cayenne along the National Road of the East to Régina, encompass a large number of protected plants and animals. Crique Orfion enjoys protection un- der Natural Zone of Ecological, Faunistic and Floristic Interest (ZNIEFF) station’s status. “Crique Orfion station with Bactris nancibaensis ” (endemic palm tree of the Guyanese littoral) includes over 3.000 hectares of drained forests, lowland swamp forests and swamp forests. Characteristic plants in the permanently flooded zones are Euterpe oleracea (Arecaceae) (‘pinot palm’,‘aÇaí palm’), Symphonia globulifera (Clusiaceae) (‘chestick’,‘manil marécage’, ‘guanandi’) and especially Lecythis pneumatophora (Lecythidaceae) (‘mahots’). In periodically exposed areas Oenocarpus bataua (Arecareae) (‘patawa’, ‘patauá’) is quite abundant in the canopy ( Tostain, 2017).