Thereus antecum Faynel & Fåhraeus sp. nov.

LSIDurn:lsid:zoobank.org:act: 4E97C256-50F2-4DBC-81CD-5DC66A76123F

Figures 8, 9, 37, 53, 69, 83, 89

Type material. Holotype male (Fig. 8), FW 17.15 mm, labelled as “ Guyane Française // 11. VII. 2008 // Roura // Cacao // Piste de la source // E. Amar Leg ” (white rectangular label, black printed); “Coll. DIRINGER” (white rectangular label, black handwritten); “CF-LYC-2165” (orange rectangular label, black printed); “CFCF155 // Thereus antecum ♂ // 23/04/2024 // Diss. Klaudia Florczyk” (green rectangular label, black printed); “Holotype ♂ // Thereus antecum // Faynel & Fåhraeus, 2025 ” (red rectangular label, black printed). The GPS data of the type locality are 04°33'36'' N, 52°27'46" W. Currently in RCCF, will be deposited in MNHN.

Paratypes (4♂, 3♀). FRENCH GUIANA. 1♂, Cacao, Prise d’eau sur Cordia, 4.5543, -52.4634, 5.xii.2020, L616, CF-LYC-1428*, coll. Nino Page & Maeva Leroy ; 1♂, Roura, Camp Patawa, jardin, light trap, 4.5443, -52.1527, 05.vi.2021, L769, NPML_lyc38, coll. Nino Page & Maeva Leroy ; 1♂, Cacao, sentier de la source, 04°33'36''N, 52°27'46"W, 6.viii.2015, coll. Louis Diringer ; 1♂, Route de Kaw, PK 16, 261m, 04°37'38''N, 52°17'30"W, 21.vii.2011, coll. Louis Diringer ; 1♀, Route de Kaw, PK 6 sur C. schomburgkii, 29.i.2006, S. Brûlé leg., Coll. C. Faynel n° 1702, CF-LYC-429*, gen. prep. K. Florczyk CFCF034 (RCCF, illustrated on Fig. 9); 1♀, Antecum Pata, 20.ii.2009, light trap, Poirier et Dalens leg., Coll. C. Faynel n° 1848, CF-LYC-449* (RCCF); 1♀, Galion, 12.vii.1995, J.Y. Gallard leg., Ex. coll. Gallard N° 137♀, gen. prep. C. Faynel 034, RCCFXPL5A07* (RCCF) .

They have now the following labels “ Paratype ♂ [or ♀] // Thereus antecum // Faynel & Fåhraeus, 2025 ” (blue rectangular label, black printed).

Diagnosis and description. Thereus antecum sp. nov. is the largest species of the group, sister to T. borbaensis sp. nov. in the phylogenetic tree (Fig. 1), from which it is distinguished by the absence of a DFW scent patch. T. antecum sp. nov. is close ventrally to T. endera, T. geminus sp. nov. and T. cacao sp. nov. with the following differences: (1) male DFW androconia slightly pointed basally with a black halo distally (Fig. 37); (2) male DHW cell Rs-M 1 completely covered by blue; (3) female dorsal coloration more grey blue; (4) only few red scales present on VHW, between cubital spot and anal spot; (5) valvae tips pointed, not rounded like the others; (5) huge mean genetic divergence: 6.56 % with T. endera, 6.83 % with T. geminus sp. nov. and 5.21 % with T. cacao sp. nov. (Table 3). Male (Fig. 8). FW length: 17.7 mm, n=2. Wings. DFW shiny metallic blue covering half the wing, oval brown scent pad, with a black halo distally. DHW blue scales covering space between veins Rs and 2A. VHW with only a few orange scales in CuA 2 -2A not connecting the anal and the cubital red spots. Male genitalia (Fig. 53). One male dissected. Characterized by a large tegumen in lateral view; dorsal processes supporting the dorsal pair of brush organs not perpendicular to the tegumen edge but turned dorsally; valvae with very sharp posterior ends; saccus narrow and pointed; penis not straight with coecum forming an arch of approximately 150° relative to the axis of the penis. Eighth tergite subrectangular, anterior border convex, posterior one almost straight. Female (Fig. 9). FW length: 19.9 mm, n =3. Wings. dull grey blue dorsally, beige-brown ventrally but lighter than male, same ventral wing pattern. Female genitalia (Fig. 69). One female dissected. Short ductus bursae but wide in ventral view. No signum observed in the corpus bursae, and no sclerotized element in between the papillae anales. Eighth tergite subrectangular, anterior border convex, posterior one concave. The association of the sexes was based on similar type locality, similar ventral wing patterns, the same COI sequence and hence the same BIN (ACK2035).

Ethology. According to label data, males and females feed on Cordia schomburgkii A. DC. ( Boraginaceae). A male was caught at 9:30am and another at 11:00am (Fig. 83). A male and a female were attracted by light trap (photo-positiveness).

Sympatry. Thereus antecum sp. nov. occurs in sympatry with T. cacao sp. nov. and T. praxioides sp. nov. in French Guiana (Figs 86, 87, 89).

Known distribution (Fig. 89). French Guiana.

Etymology. Antecume-Pata is a village on the Maroni River, southwest of French Guiana, near the border with Suriname, where Wayana ethnic group is living. It was founded at the initiative of André Cognat (1938- 2021). Antecume was his Wayana adopted name. One of the female paratype of the new species has been found by members of the French Guiana Entomological Society during a light trap organized near this village. It is a noun in apposition, not latinized.

Remarks. This species was wrongly identified as T. genena (Faynel 2010) .