Vertex straight (Fig. 3C); frons convex in lateral view (Fig. 3D); labrum connate to fronto-clypeus, frontoclypeo-labral suture obliterate (Fig. 3C); gular margins contiguous and straight (Fig. 3B); antenna serrate, with ten antennomeres (Fig. 3G, H); pronotum rectangular, with punctures contiguous or separated by 0.1× the puncture width, except for two raised tubercles on the posterior ½ of the disc with sides divergent posteriorly (Figs 4A, 6A); elytron slightly dehiscent (i.e., sinuose inner margin) (Fig. 6A–C); suture between mesanepisternum and mesoventrite visible (Fig. 5C); metathoracic discrimen as long as 3/4 of sternite length (Fig. 5C); lanterns occupying the entire area of sternite VI and VII (Figs 2A, 7A); pygidium with posterior margin bisinuate (Fig. 8E); ventral plate of phallus deeply bilobate (Fig. 8C), phallobase symmetrical (Fig. 8A–C).

Figure 2. 

Memoan conani sp. nov., male habitus A ventral B lateral C dorsal. Scale bar: 1 mm.

Figure 3. 

Memoan conani sp. nov., head A dorsal B ventral C frontal D lateral E posterior F occipital; antenna G dorsal H lateral. Scale bar: 0.5 mm (A–H). Note the gular margins contiguous (arrow).

Male. Head. Capsule 1.5× wider than long (Fig. 3A); vertex straight (Fig. 3C); eyes separated by 2/3 of head width in frontal view (Fig. 3C) and each eye as wide as 2/3 of head width in dorsal view (Fig. 3A); frons raised and convex in lateral view (Fig. 3D); labrum connate to fronto-clypeus, frontoclypeo-labral suture obliterate (Fig. 3C); gular margins contiguous and straight (Fig. 3B); antennal insertion with outer margin straight, inner margin rounded, as wide as labrum (Fig. 3C). Antenna serrate, with 10 antennomeres (Fig. 3G, H; but may the apical antennomere may be subdivided; see Discussion), as long as 1/2 of body length (Fig. 2A–C); pedicel as long as wide (Fig. 3G); antennomere IV 1.5× longer than III, V–IX subequal in length, X as long as IV (Fig. 3G, H). Maxillary palp with palpomeres I and III 2× wider than long (Fig. 3A–D), II and IV 1.5× wider than long. Labial palp with one or two palpomeres, apical palpomere digitiform (Fig. 3B, F; Silveira and Mermudes 2013: fig. 5). Mentum completely longitudinally divided (Fig. 3B); gular margins contiguous and straight (Fig. 3B). Occipital foramen ellipsoid in posterior view (Fig. 3E, F). Thorax. Pronotum rectangular (Fig. 4A, B), 2× longer than head length in ventral view (Fig. 2A), 1.5× longer than wide in dorsal view (Fig. 4A), with punctures contiguous or separated by 0.1 puncture width, except for two elongate tubercles on the posterior 1/2 of the disc, sides of tubercles divergent posteriorly (Figs 4A, 6A); hypomeron 2.5× longer than tall (Fig. 4C), with punctures contiguous or separated by 0.1× the puncture width (Fig. 4C); prosternum 0.5× as wide as pronotum in ventral view (Fig. 4B); proendosternite as long as 1/5 of prosternum width (Fig. 4B). Mesocutellum with wide, irregular shaped punctures, contiguous or separated by 0.1× puncture width (Fig. 5A). Elytron slightly dehiscent (i.e. sinuose inner margin), each subparallel-sided (Fig. 6A–C), almost 6× longer than wide. Hind wing (Fig. 6D) with vein r4 poorly sclerotized apically; radial cell poorly sclerotized posteriorly, 2× to 3× wider than long; vein r3 present or absent, vein CuA1 and CuA3+4 present or absent, vein J evanescent as long as 1/4 AP3+4 length (Fig. 6D, Silveira and Mermudes 2013: fig. 8). Metanotum 1.5× wider than long, posterior margin straight, allocrista distinct, well-sclerotized (Fig. 5B). Mesoventrite sclerotized (Fig. 5C), posterior margin rounded; suture between mesanepisternum and mesoventrite visible (Fig. 5C); mesendosternum with irregular flap-like projections (Fig. 5E); metaendosternum spatulate, diamond-shaped (Fig. 5D); metathoracic discrimen as long as 3/4 of sternite length (Fig. 5C). Tibial spurs absent (Fig. 6E–G), procoxa distally constricted, femur as long as tibia, tarsus I>V>II>IV>III (Fig. 6E–G). Abdomen. Lanterns occupying the entire area of sternite VI and VII (Figs 2A, 7A); sternite VIII 3× wider than long, lateral margins rounded, posterior margin mucronate (Fig. 8E). Sternite IX symmetrical (Fig. 8D), 3× longer than wide, posterior margin rounded. Pygidium as long as wide (Fig. 8F), posterior margin bisinuate, posterolateral angles acute, median 1/3 extending slightly beyond posterolateral angles. Phallus with dorsal and ventral plates overlapping mesal concavity of phallobase (Fig. 8A–C); dorsal plate shorter than ventral plate, ventral plate deeply cleft medially, forming two lobes, apical lobes bent dorsad; parameres symmetrical and broadly rounded at apex in dorsal and lateral views, anterior margin rounded, apically separated from each other and 0.5× shorter than phallus; phallobase symmetrical (Fig. 8A–C).

Figure 4. 

Memoan conani sp. nov., pronotum A dorsal B ventral C lateral D posterior. Scale bar: 1 mm (A–D). Note the L-shaped sclerotized raised tubercles, and proendosternite (arrows). L: length; H: height.

Figure 5. 

Memoan conani sp. nov., mesoscutellum A dorsal; metanotum B dorsal; pterothorax C dorsal; mesoendoesternite D dorsal; metaendoesternite E dorsal. Scale bars: 200 µm (A, D–E); 2 mm (B, C). Note the sutures between mesoventrite/mesanespisternum and mesanepisternum/mesepimeron, the metathoracic discrimen, and irregular flap-like projections on mesendosternum (arrows).

Figure 6. 

Memoan conani sp. nov., elytra A dorsal B lateral C ventral; right wing D dorsal; proleg E lateral; mesoleg F lateral; metaleg G lateral. Scale bar: 1 mm (A–G).

Figure 7. 

Memoan conani sp. nov., abdomen A ventral B lateral C dorsal. Scale bar: 1 mm (A–C).

Figure 8. 

Memoan conani sp. nov., aedeagus A dorsal B lateral C ventral; sternum IX D ventral; sternite VIII E ventral; pygidium F dorsal. Scale bars: 200 um (A–D); 2 mm (E, F).

Females and immature stages. Unknown.

The discovery of a second species of Memoan (see below) called for an updated diagnosis for this genus. Memoan is distinguishable from other amydetine genus by their serrate antennae. Silveira and Mermudes (2013) pointed out that Memoan shares the following traits with the other amydetine genera: continuous glow (present in Amydetes spp. and Magnoculus spp.); eyes ventrally close-set (present in some species of Magnoculus; Constantin 2011); labial and maxillary apical palpomere with rounded apex (present in Amydetes spp. and Magnoculus spp.); punctures wide and irregularly outlined on pronotum and scutellum, sometimes on hypomeron as well (widespread in Magnoculus spp., absent from disc in Amydetes spp.). Recent phylogenetic studies based on molecular data corroborate a placement in Amydetinae (Martin et al. 2019). The evolutionary history of these traits is yet to be assessed.

After studying Maurice Pic’s collection at the MNHN, we found that the holotype P. fruhstorferi of examined had all the diagnostic traits of Me. ciceroi (e.g., antenna with 10 antennomeres, apical antennomere subdivided, labial palp with one palpomere; Silveira and Mermudes 2013). Therefore, we propose that Me. ciceroi is a subjective junior synonym of P. fruhstorferi Pic, 1942.

Pic (1942: 16) described P. fruhstorferi as follows: “angustatus et elongatus, testaceus. Long. 6 m, Bresil, - Character par sa coloration claire jointe à sa forme élancée”. The current definition of Photinus is controversial, as pointed out by several firefly specialists (e.g., McDermott 1964), and needs taxonomic revision. In fact, P. fruhstorferi does not have characters normally found in Photinus, such as simple antennae shorter than 1/2 body length, pronotum with sides white and laterally expanded, abdominal tergites rounded, and phallobase relatively long (McDermott 1964). Therefore, we transfer P. fruhstorferi to Memoan, generating Me. fruhstorferi (Pic, 1942) comb. nov. and synonymize it with Me. ciceroi, syn. nov., over which it has priority.

Holotype : Bearing the label: “Espírito Santo. Brasil. ex coll Fruhstorfer.” [aged green label, typewritten]; “TYPE” [aged red label, typewritten]; “R Fruhstorferi” [aged white label, handwritten] (MNHN; Suppl. material 1: Fig. S1).

The specific epithet conani is a masculine noun in the genitive case. The species is named in honor of Mauricio Conan Mendes Correa de Oliveira. Conan was a biology student at the Universidade Federal do Rio de Janeiro, deceased since January 2019, and was a dear friend of the first author.

Labial palp with two palpomeres (Fig. 3B, F); scape as long as pedicel (Fig. 3G, H); apical antennomere entire, lacking a subdivision or vestigial joint (Fig. 3G, H).

Male. Coloration. Tegument dark brown (Fig. 2A–C); antennae dark brown (Fig. 3G, H); pronotum and elytra dark brown (Figs 4A, 6A); abdomen with sternites VI–VIII and tergite VIII translucent (Fig. 7A–C); pygidium translucent (Fig. 8F). Head. Antennal insertions separated by 0.5× socket width in frontal view (Fig. 3C); scape as long as pedicel (Fig. 3G, H); antennomere III 2× longer than pedicel (Fig. 3G, H); apical antennomere entire, lacking a subdivision or vestigial joint (Fig. 3G, H); compare with Silveira and Mermudes 2013: fig. 6). Labial palp with two palpomeres 2-segmented (Fig. 3B, C, F). Thorax. Hind wing with radial cell 3× wider than long (Fig. 6D). Mesoscutellum with posterior margin almost straight (Fig. 5A). Abdomen. Phallus 2× longer than parameres (Fig. 8C); parameres with margins evenly rounded and slightly wider than phallus. (Fig. 8 A–C).

Females and immature stages. Unknown.

Twenty-three individuals were collected in hilly areas in the Pedra Branca massif (Fig. 1) at 400 m above sea level. All specimens were collected in a single, shaded humid, approximately 45° slope. Twelve specimens were collected by active search in April 2017 and eleven in April 2019. Males have a continuous green glow and often fly between 0.5 and 3 m above the ground, often in the understory, sometimes reaching up to roughly 7 m above the ground in the forest canopy. Adults are apparently active in the early twilight hours. Males lack the distinctive smell, similar to marzipan frosting, which has been reported for the type species (Silveira and Mermudes 2013). About 2–5 males were observed flying close together in the same visual field.

Memoan conani sp. nov. is the second species described in the genus. The differences between species are marked: labial palp (with one palpomere in Me. fruhstorferi comb. nov. and with two palpomeres in Me. conani sp. nov.), which differs morphologically from the all other lampyrids as by Branham (2010); scape (2× longer than pedicel in Me. fruhstorferi comb. nov. and as long as pedicel in Me. conani sp. nov.); antennae (serrate, with 10 antennomeres in Me. conani sp. nov. and Me. fruhstorferi comb. nov., but in Me. fruhstorferi comb. nov. antennomeres X and XI are connate; see Silveira and Mermudes 2013). Silveira and Mermudes (2013) described the gular suture as biconcave, but, after re-examination of the material, we observed that these are actually straight throughout most of their length, but slightly divergent posteriorly in both species.

Both species of Memoan occur in remnants of montane forests, separated from one another by a distance of 400 km: Me. fruhstorferi comb. nov. occurs at the Santa Lúcia Biological Station, in Espírito Santo state, whereas Me. conani sp. nov. occurs at the Massif of Pedra Branca, Rio de Janeiro state. Since fireflies are poor dispersers (Silveira et al. 2016a), we hypothesize that Memoan is endemic to the Atlantic Forest biome, as it has never been found elsewhere in the field despite extensive surveys (Silveira et al. 2020) and is not present in multiple collections in Brazil (DZUP, INPA, MNRJ, MZSP) and abroad (MNHN, ZMHB). This pattern of endemicity is also seen in several other groups of fireflies (e.g., Amydetes; Luciuranus; Araucariocladus; and Uanauna).

Memoan conani sp. nov. were only seen in a narrow spatial and temporal window; that is, males were only observed and collected in a single slope within the limits of the PEPB at an altitude around 400 m a.s.l., and only in April. Likewise, Me. fruhstorferi comb. nov. has only been collected at about 600 m a.s.l., also exclusively in April. Such narrow environmental preferences have been reported for most firefly species occurring in the Atlantic Forest (Silveira et al. 2020). Given the narrow geographic range, both Me. conani sp. nov. and Me. fruhstorferi comb. nov. may be seriously threatened by habitat loss, like many other Atlantic Forest endemics.

Holotype : Brazil • Rio de Janeiro: Rio de Janeiro: Parque Estadual da Pedra Branca, Núcleo Camorim, Trilha do Açude, 22°58'03.7"S, 43°26'45.7"W; 400 m a.s.l.; ♂; 12 Apr. 2017; L. Silveira, L. Campello, S. Vaz, A.L. Diniz leg. (DZRJ). Paratypes: Brazil • same data as for holotype; 10 males (DZRJ) • same data as for holotype; 1 ♂; 9 Apr. 2017; A.L. Diniz leg. (DZRJ) • same data as for holotype; 11 ♂; 13 Apr. 2019; L. Campello, A.L. Diniz, E. Atílio leg. (MNRJ).

The specific epithet marolae is a feminine noun in the genitive case. This species is named in honor of our colleague and friend, Raquel Santos Soares Queiroz, alias “Marola”, who helped us collect the type specimens.

Antennae with scape and pedicel yellowish brown (Fig. 10G), flagellum light brown (Fig. 10G); pronotum yellowish brown (Fig. 11A–D); abdomen dark brown, with sternites VI–VIII translucent (Figs 9A, 12E), pygidium dark brown with a translucent posterior line (Fig. 12F); antennae with 32–41 antennomeres (Fig. 10G); antennomere III with flabellum 2× longer than antennomere III; antennomere III as long as scape (Fig. 10G); maxillary apical palpomere 10× longer than III (Fig. 10A, B); hypomeron as long as tall (Fig. 11C); sternite VIII with posterior margin bisinuate, central 1/3 slightly shorter than posterolateral angles (Fig. 12E); lanterns occupying almost the entire area of sternite VI and VII (Fig. 9A).

Figure 9. 

Amydetes marolae sp. nov., male habitus A ventral B lateral C dorsal. Scale bar: 1 mm (A–C).

Figure 10. 

Amydetes marolae sp. nov., head A dorsal B ventral C frontal D lateral E posterior F occipital; antennae G dorsal. Scale bars: 1 mm (A–F); 2 mm (G). GB: gular bar.

Figure 11. 

Amydetes marolae sp. nov., pronotum A dorsal B ventral C lateral D posterior. Scale bar: 1 mm (A–D).

Figure 12. 

Amydetes marolae sp. nov., aedeagus A dorsal B lateral C ventral; sternum IX D ventral; sternite VIII E ventral; pygidium F dorsal. Scale bars: 0.5 mm (A–D); 1 mm (E, F).

Male. Coloration. Antennae with scape and pedicel yellowish brown (Fig. 10G), flagellum pale brown (Fig. 10G); pronotum yellowish brown (Fig. 11A–D); abdomen dark brown, with sternites VI– VIII translucent (Figs 9A, 12E), pygidium dark brown with a translucent posterior line (Fig. 12F). Head. Antennae flabellate with 32–41 antennomeres (Fig. 10G); antennomere III as long as pedicel, with flabellum 2× longer than antennomere III (Fig. 10G). Fronto-clypeus as wide as 1.5× distance between antennifers process (Fig. 10C). Maxillary palpomere I as long as wide; II 2× longer than wide, III approximately 0.1× of IV length (Fig. 10A–F). Gular margins separated by 1/3 maxillary palpomere IV length (Fig. 10B). Thorax. Pronotum 1.5× wider than head width in ventral view (Fig. 9A), 1.5× wider than long (Fig. 11A, B). Hypomeron as long as tall (Fig. 11C). Abdomen. Lanterns occupying almost the entire area of sternite VI and VII (Fig. 9A). Sternite VIII with posterior margin bisinuate, central 1/3 slightly shorter than posterolateral angles (Fig. 12E). Pygidium with a translucent posterior line (Fig. 12F). Phallus 1.5× longer than parameres (Fig. 12A–C); parameres basally constricted, as long as phallobase (Fig. 12A); phallobase asymmetrical (Fig. 12A, C).

Females and immature stages. Unknown.

One hundred forty-six individuals were collected in hilly areas of the Ilha Grande State Park (Fig. 1) between 160–660 m a.s.l. in 2017 and 2018. The highest abundance was observed between 160–170 m a.s.l. This species has a continuous blue-green glow. Males fly between 0.1 and 4 m above ground level, bending their abdomens downward, possibly to light the ground in search of females, (as in other Amydetes spp.; Vaz et al. 2021); they sometimes flying upwards towards the forest canopy. They are apparently active in the first hours of complete darkness. About 5–10 males were observed flying together in the same visual field.

Amydetes marolae sp. nov. is similar to A. bellorum, with which it shares the following combination of traits: labrum connected to fronto-clypeus by membrane; maxillary palpomere IV at least 6× longer than III (up to 7× in A. bellorum, and at least 10× in A. marolae sp. nov.); hypomeron as long as tall; and sternite VIII bisinuate. Nevertheless, Amydetes marolae sp. nov. differs from A. bellorum by: body length (average = 0.67 mm [n = 10, range = 0.6–0.8] in A. marolae and 0.87 mm [n = 10, range = 0.8–1.0] in A. bellorum); pygidium (entirely dark brown in A. bellorum, dark brown with a translucent posterior line in A. marolae sp. nov.).

Amydetes marolae sp. nov. occurs in a mountainous and coastal region of the Serra do Mar range, where it is found between 160 and 660 m a.s.l., with greater abundance in parts below to 400 m a.s.l. Despite extensive sampling (e.g., Silveira et al. 2020), A. marolae sp. nov. has never been collected anywhere other than Ilha Grande, unlike A. bellorum which does not occur on Ilha Grande. Ilha Grande is separated by approximately 3 km from the mainland, which may be an important barrier to dispersal, especially considering that Amydetes females are perhaps flightless (Silveira and Mermudes 2014a). As such, A. marolae sp. nov. is regarded here as probably endemic to Ilha Grande.

Holotype : Brazil • Rio de Janeiro: Angra dos Reis: Parque Estadual da Ilha Grande, Pico do Papagaio; 23°09'05.8"S, 44°11'19.9"W; 660 m a.s.l.; ♂; Apr. 2018; L. Campello, L. Silveira, R. Queiroz, S. Vaz leg. (DZRJ). Paratypes: Brazil • Rio de Janeiro: Angra dos Reis: Parque Estadual da Ilha Grande, Estrada para Dois Rios, Poço do Soldado; 23°10'04.7"S, 44°11'03.5"W; 160 m a.s.l.; 7 ♂; Jul. 2018; L. Campello, L. Silveira, S. Vaz, R. Queiroz leg. (DZRJ) • same data as for preceding; 2 ♂; Sep. 2017 (DZRJ) • same data as for preceding; 2 ♂; Oct. 2017 (DZRJ) • same data as for preceding; 2 ♂; Dec. 2017 (DZRJ) • same data as for preceding; 24 ♂; Mar. 2018 (DZRJ) • same data as for preceding; 11 ♂; Apr. 2018 (DZRJ) • same data as for preceding; 20 ♂; May. 2018 (DZRJ) • same data as for preceding; 11 ♂; Jun. 2018 (DZRJ) • same data as for preceding; 18 ♂; Aug. 2018 (DZRJ) • same data as for preceding; 1 ♂; Nov. 2018 • same data as for preceding; 23°10'05.7"S, 44°11'04.0"W; 170 m a.s.l.; 1 ♂; Sep. 2017; (MNRJ) • same data as for preceding; 1 ♂; Oct. 2017 (MNRJ) • same data as for preceding; 1 ♂; Jan. 2018 (MNRJ) • same data as for preceding; 3 ♂; Apr. 2018 (MNRJ) • same data as for preceding; 7 ♂; May. 2018 (MNRJ) • same data as for preceding; 5 ♂; Jun. 2018 (MNRJ) • same data as for holotype; 23°08'49.9"S, 44°10'51.5"W; 335 m a.s.l.; 1 ♂; Nov. 2017 (MNRJ) • same data as for preceding; 2 ♂; Dec. 2017 (MNRJ) • same data as for preceding; 1 ♂; Feb. 2018 (MNRJ) • same data as for preceding; 1 ♂; Apr. 2018 (MNRJ) • same data as for preceding; 3 ♂; Jul. 2018 (MNRJ) • same data as for preceding; 1 ♂; Aug. 2018 (MNRJ) • same data as for holotype; 23°08'51.5"S, 44°10'52.4"W; 345 m a.s.l.; 3 ♂; Oct. 2017 (MNRJ) • same data as for preceding; 1 ♂; Nov. 2017 (MNRJ) • same data as for preceding; 2 ♂; Jan. 2018 (MNRJ) • same data as for preceding; 1 ♂; Mar. 2018 (MNRJ) • same data as for preceding; 1 ♂; May. 2018 (MNRJ) • same data as for preceding; 5 ♂; Jul. 2018 (MNRJ) • same data as for holotype; 23°08'47.2"S, 44°11'09.4"W; 440 m a.s.l.; 1 ♂; Jun. 2018 (MNRJ) • same data as for preceding; 6 ♂; Aug. 2018 (MNRJ).

The specific epithet alexi, is a masculine noun in the genitive case. This species is named in honor of Alex Schomaker Bastos, our dearest friend and biology student at the Universidade Federal do Rio de Janeiro, who was murdered on 8 January 2015.

Antennae with scape and pedicel yellowish brown (Fig. 14G), flagellum dark brown (Fig. 14G); pronotal disc dark brown with margins yellowish brown (Fig. 15A, B); elytra dark brown with outer margin yellow (Fig. 13A–C); posterolateral margin of thorax yellowish brown (including the posterior corners of metaepisternum and metaepimeron, in addition to the anterior portion of metacoxa; Fig. 13A); legs yellowish brown darkened to dark brown toward apex (Fig. 13A); sides of sternites II–V translucent (Fig. 13A); sternite VIII translucent (Fig. 16E); antennae with 33–37 antennomeres (Fig. 13G); antennomere III 0.5× longer than scape (Fig. 14G); maxillary and labial apical palpomere subequal in length (Fig. 14A–E); hypomeron as long as tall (Fig. 15C); lantern occupying the posterior 1/2 of the sternites VI and VII, and 3/4 the width of these sternites (Fig. 13A).

Figure 13. 

Amydetes alexi sp. nov., male habitus A ventral B lateral C dorsal. Scale bar: 2 mm (A–C).

Figure 14. 

Amydetes alexi sp. nov., head A dorsal B ventral C frontal D lateral E posterior F occipital; antennae G dorsal. Scale bars: 1 mm (A–F); 2 mm (G).

Figure 15. 

Amydetes alexi sp. nov., pronotum A dorsal B ventral C lateral D posterior. Scale bar: 1 mm (A–D).

Male. Coloration. Antennae with scape and pedicel yellowish-brown (Fig. 14G), flagellum dark brown (Fig. 14G); pronotal disc dark brown with margins yellowish brown (Fig. 15A, B); elytra dark brown with outer margin yellow (Fig. 13A–C); posterolateral margin of thorax yellowish brown (Fig. 13A); legs yellowish brown darkened to dark brown toward apex (Fig. 13A); sides of sternites II–V translucent (Fig. 13A); sternite VIII translucent (Fig. 16E). Head. Antennae flabellate with 33–37 antennomeres (Fig. 14G); antennomere III 1/2× longer than scape, with flabellum 3× longer than antennomere III. Fronto-clypeus as wide as 1/2 distance between antennifers process (Fig. 14C). Maxillary and labial apical palpomere subequal in length (Fig. 14A–E); maxillary palpomere I, II and IV 2× longer than wide, III 2× wider than long, I 2/3× longer than II, II approximately 2× longer than III, IV approximately 3× longer than III (Fig. 14A–D). Gular margins separated by 1/2 length of maxillary palpomere IV (Fig. 16B). Thorax. Pronotum 1.5× wider than head width in ventral view (Fig. 13A), 1.5× wider than long (Fig. 15A). Hypomeron as long as tall (Fig. 15C). Abdomen. Lanterns occupying the posterior 1/2 of sterna VI and VII, as wide as 2/3 the width of these sternites (Fig. 13A). Sternite VIII with posterior margin bisinuate, central 1/3 longer than posterolateral angles (Fig. 16E). Pygidium 1.5× wider than long (Fig. 16F), with posterior margin bisinuate, postero-lateral projections as long as 1/5 length of the central projection. Phallus 1.5× longer than parameres (Fig. 16A–C); parameres basally constricted, 2× longer than phallobase (Fig. 16A–C); phallobase asymmetrical (Fig. 16A, C).

Figure 16. 

Amydetes alexi sp. nov., aedeagus A dorsal B lateral C ventral; sternum IX D ventral. sternite VIII E ventral; pygidium F dorsal. Scale bars: 0.5 mm (A–D); 1 mm (E–F).

Females and immature stages. Unknown.

Forty-five individuals were collected in hilly areas in the Pedra Branca State Park (Fig. 1), between 140 and 800 m a.s.l. Twelve were collected using Malaise traps: four at 250 m a.s.l. and nine at 280 m a.s.l. All individuals were collected between May and August 2017, which are relatively cooler months. Despite limited sampling, we noticed that the greatest abundance was found around 250–500 m a.s.l., with 23 individuals collected. One specimen, collected on 4 October 2017, was actively flying during daylight (~13:00), suggesting that this species is diurnal, which is congruent with the species’ morphology (i.e., smaller eyes and lanterns; Silveira and Mermudes 2014a).

Amydetes alexi sp. nov. differs from A. bellorum and A. marolae sp. nov. in the length of maxillary palpomere IV, which is at least 6× longer than III in A. marolae sp. nov. and A. bellorum, but only 3× longer than III in three species: A. itatiaia, A. apicalis, and A. alexi sp. nov. Amydetes alexi sp. nov. differs from A. itatiaia in the length of flabellum of antennomere III (3× longer than pedicel in A. alexi sp. nov., but equal in A. itatiaia). The new species shares the following traits with A. apicalis: pronotum with posterolateral angles pointed but weakly developed; flabellum of antennomere III 3× longer than pedicel; and phallobase asymmetrical. Nevertheless, A. alexi sp. nov. differs from A. apicalis in having antennae with 33–37 antennomeres (37–44 in A. apicalis) and lantern of sternite VI up to 1/2 sternite length (3/5 in A. apicalis). The distribution of A. alexi sp. nov. is apparently restricted to Pedra Branca massif, as it has not been found nearby by our team (e.g., Silveira et al. 2020).

Holotype : Brazil • Rio de Janeiro: Rio de Janeiro: Taquara, Núcleo Pau da Fome, Rio da Fazenda; 285 m a.s.l.; ♂; 6 Aug.–3 Sep. 2017; A. Diniz leg. (DZRJ).

Paratypes : Brazil • Rio de Janeiro: Rio de Janeiro: Taquara, Núcleo Pau da Fome, Trilha para o açude; 1 ♂; 7–10 May. 2017; L. Silveira, A. Diniz leg. (MNRJ) • same data as for preceding, Afluente do Rio Grande, perto da Cachoeira Sete Quedas; 255 m a.s.l.; 4 ♂, 22–19 Jun. 2017; A. Diniz leg. (MNRJ) • same data as for preceding; 3 ♂; 19 Jun.–19 Jul. 2017; A. Diniz leg. (DZRJ) • same data as for preceding, Próximo às ruínas; 5 ♂; 23 Jun.–4 Aug. 2017, A. Diniz leg. (MNRJ) • same data as for preceding, Travessia para o Rio da Prata; 800 m a.s.l.; 3 ♂; 20 Jul. 2017; A. Diniz leg. (MNRJ) • same data as for preceding; 450 m a.s.l.; 8 ♂ 8 Aug.–4 Sep. 2017; L. Silveira, A. Diniz leg. (DZRJ) • same data as for preceding; 300–400 m a.s.l.; 4 ♂; 4 Sep. 2017, L. Silveira leg. (DZRJ) • 22°55'59,7"S, 43°26'29,0"W; 140 m a.s.l., 12 ♂; J. Nessimian, L. Dumas, T. Almeida, B. Genário, L. Diniz leg. (DZRJ) • same data as for holotype; 4 ♂ (MNRJ).

Elytra with inner margin dehiscent (i.e., sinuose inner margin) at posterior 1/3 (Fig. 17C); pronotum semilunar, with rounded and obtuse posterolateral angles (Fig. 19A, B), 2× wider than long; frons raised (Fig. 18D); eyes separated by the same length of maxillary palpomere III (Fig. 18B); antennomere III as long as wide (Fig. 18G); antennae shorter than 0.5× body length (Fig. 17A–C); posterior margin of mesoscutellum straight (Fig. 20A); phallobase symmetrical (Fig. 23A–H); sternite IX symmetrical (Fig. 23I); pygidium with posterior margin bisinuate (Fig. 23K).

Figure 17. 

Magnoculus obscurus, male habitus A ventral B lateral C dorsal. Scale bar: 1 mm (A–C).

Figure 18. 

Magnoculus obscurus, head A dorsal B ventral C frontal D lateral E posterior F occipital; antennae G dorsal H lateral. Scale bar: 0.5 mm (A–H). Note the gular margins contiguous (arrow).

Figure 19. 

Magnoculus obscurus, pronotum A dorsal B ventral C lateral D posterior. Scale bar: 1 mm (A–D). Note the raised tubercle (arrow).

Figure 20. 

Magnoculus obscurus, mesoscutellum A dorsal; metanotum B dorsal; pterothorax C dorsal; mesoendoesternite D dorsal; metaendoesternite E dorsal. Scale bars: 500 µm (A, D–E); 1 mm (B, C). Note the sutures between mesoventrite/mesanespisternum and mesanepisternum/mesepimeron; the metathoracic discrimen; and flap-like projections on mesendosternum (arrows).

Male. Coloration. Antennae dark brown (Fig. 18G, H); pronotum brown, with two sclerotized raised tubercles dark brown on the posterior 1/2 (Fig. 19A, B); elytron dark brown (Fig. 21A–C); abdomen completely dark brown (Fig. 22A–C). Head. Capsule 1.5× wider than long (Fig. 18A); vertex convex (Fig. 18C); eyes separated by 2/3 of head width in frontal view (Fig. 18C); frons raised (Fig. 18D); labrum connate to fronto-clypeus, frontoclypeo-labral suture obliterate (Fig. 18C); antennal insertions rounded (Fig. 18C, D), separated by 0.5× labrum width. Antennae flabellate, lamellae stiff and laterally compressed, with 11 antennomeres (Fig. 18G, H), as long as 1/3 of body length (Fig. 17A–C); pedicel 2× wider than long (Fig. 18G, H), III–V subequal in length, V–IX subequal in length, IX–X subequal in length. Maxillary palp with four palpomeres (Fig. 18B), II–IV subequal in length, III 2× longer than I. Labial palp with three palpomeres (Fig. 18B), I–II subequal in length, III 2× longer than II. Occipital foramen subcordiform in posterior view (Fig. 18E, F). Thorax. Pronotum semilunar (Fig. 19A–D), almost 2× longer than head length in ventral view (Fig. 17A), 2× wider than long in dorsal view (Fig. 19A), with contiguous and equidistant punctures along the entire surface, except for two sclerotized raised tubercles on the posterior 1/2, equidistant from sides (Fig. 19A, D); hypomeron 2× longer than tall (Fig. 19C); prosternum wider than 1/5 of pronotum width in dorsal view (Fig. 19B). Elytron slightly dehiscent (i.e., sinuose inner margin), subparallel-sided (Fig. 21A–C). Hind wing (Fig. 21D) with radial cell evanescent, 2× wider than long; vein r3 as long as 1/4 r4 length, vein CuA1 absent; vein CuA3+4 present; vein J as long as 1/3 the length of vein AP3+4. Metanotum as long as wide, posterior margin emarginate medially, allocrista distinct (Fig. 20B). Mesoventrite sclerotized (Fig. 20B), posterior margin rounded; suture between mesoventrite and mesanepisternum visible (Fig. 20C), mesendosternum with two irregular, flap-like projections (Fig. 20E); metaendosternum spatulate, diamond-shaped (Fig. 20D). Tibial spurs absent (Fig. 21E–G), tarsus I >V >IV>II=III (Fig. 21E–G). Abdomen. Lanterns occupying almost the entire area of sternite VI and VII (Fig. 17A); sternites II–VII with sides rounded (Fig. 22A), II, III, VI and VII with posterior margin medially emarginate; sternite VIII mucronate (Fig. 23J); sternite IX symmetrical (Fig. 23I), 1.5× longer than wide, posterior margin rounded. Pygidium 1.5× wider than long (Fig. 23K), sides rounded, posterior margin bisinuate (Fig. 8F), posterolateral angles obtuse, central 1/3 extending slightly longer than posterolateral angles (Fig. 23K). Phallus with a dorsal and ventral plate (Fig. 23H, I) dorsal plate acuminate from apical 1/2 on, skewed to the anatomical left (i.e. left of the specimen), extending about a 1/4 longer than ventral plate towards the base (Fig. 23A, B, F, G), ventral plate bilobed (Fig. 23B–E), lobes spoon-shaped and separated by a deep cleft reaching basal 2/5, projected dorsolaterally to right under dorsal plate, dorsal plate extending a 1/3 beyond parameres; parameres symmetrical and spatulate (Fig. 23A, D, F, H), anterior margin rounded, apically separated from each other (i.e., not fused), and 1/2 shorter than the phallus (Fig. 23A); phallobase symmetrical (Fig. 23A).

Figure 21. 

Magnoculus obscurus, elytra A dorsal B lateral C ventral; right wing D dorsal; proleg E lateral; mesoleg F lateral; metaleg G lateral. Scale bar: 1 mm (A–G).

Figure 22. 

Magnoculus obscurus, abdomen A ventral B lateral C dorsal. Scale bar: 1 mm (A–C).

Figure 23. 

Magnoculus obscurus, aedeagus A dorsal B left dorsolateral C lateral D left lateroventral E ventral F right lateroventral G lateral H right dorsolateral; sternum IX I ventral; sternite VIII J ventral; pygidium K dorsal. Scale bars: 200 µm (A–H); 500 μm (I); 1 mm (J, K).

Females and immature stages. Unknown.

Fourteen individuals were collected in hilly areas in Ilha Grande State Park between 160–345 m a.s.l. Six specimens were collected using Malaise traps: three at 160 m a.s.l. in August 2017, December 2017, and January 2018; two at 170 m a.s.l. in November 2017 and April 2018; one at 345 m a.s.l. in August 2017. In addition, nine specimens were collected by active searches in July 2017 (five specimens), September 2017 (two specimens), and July 2018 (two specimens). Ma. obscurus has a yellowish-green glow, and males often fly between 0.1 and 4 m a.s.l., sometimes reaching up to approximately 7 m a.s.l. towards the forest canopy. Adults are apparently active in the early twilight hours. About five to ten males were observed flying close together in the same visual field.

Magnoculus obscurus is the second species of genus to be redescribed (see Zaragoza-Caballero 1995 for redescription of Ma. cf. guatemalae). The few species recently studied and illustrated in detail by Constantin (2011) and Zaragoza-Caballero (1995) allowed us to find interesting commonalities and differences among Magnoculus species. For example, Ma. obscurus shares the following characteristics with its congeners: elytra with three raised costae; pronotum with two sclerotized raised tubercles on the posterior 1/2 and posterior angles obtuse; and sternite VIII mucronate.

A comparison of Ma. obscurus with species described and illustrated in detail by Constantin (2011) and Zaragoza-Caballero (1995) is given here, as follows: antennae smaller than 1/2 body length, similar to Ma. dalensi and Ma. touroulti, but longer than 1/2 body length in Ma. brulei, Ma. dewynteri, Ma. poirieri, and Ma. guatemalae; flabellum of antennomere III as long as pronotum length, similar to Ma. touroulti and Ma. guatemalae, but 0.5× shorter in Ma. dalensi, ~2.5× longer in Ma. brulei, Ma. poirieri, and Ma. dewynteri; eyes ventrally close-set in Ma. obscurus, similar to Ma. touroulti and Ma. brulei, but not in Ma. guatemalae and Ma. dewynteri (undescribed in Ma. dalensi and Ma. poirieri); gular margins contiguous in Ma. obscurus, Ma. guatemalae, and Ma. touroulti, but open in Ma. dewynteri (no information for Ma. dalensi, Ma. poirieri, and Ma. brulei); pronotum semilunar, 2× wider than long, similar to Ma. touroulti, Ma. brulei, and Ma. guatemalae, but as wide as long in Ma. dalensi, triangular and as wide as long with anterior margin rounded in Ma. poirieri and Ma. dewynteri, completely yellow in Ma. poirieri, brown with an orange anterior spot in Ma. dewynteri, and completely dark brown in Ma. obscurus, Ma. brulei, Ma. dalensi, and Ma. tourolti. Pronotal disc with two sclerotized raised tubercles on the posterior 1/2, similar to Ma. brulei, Ma. poirieri, Ma. dewynteri, and Ma. tourolti, which are reduced in Ma. dalensi. Pygidium bisinuate in Ma. obscurus, as in Ma. dalensi and Ma. guatemalae, but semilunar in Ma. brulei, Ma. dewynteri, Ma. poirieri, and Ma. touroulti. Aedeagus of Ma. obscurus asymmetrical, as in Ma. guatemalae, Ma. poirieri, and Ma. touroulti, but symmetrical in Ma. brulei, Ma. dewynteri, and Ma. dalensi.

Bearing the labels: “SYNTYPE. Megalophthalmus. obscurus. Olivier, 1885. MNHN, Paris-co E. Olivier” [aged red label, typewritten]; “Muséum Paris. Coll. E. Olivier” [green label, typewritten]; “Brésil.” [aged white label, typewritten]; “Sahlberg.” [aged white label, typewritten]; “obscurus. Brésil ‘oliv’ [aged white label with green margins] (MNHN, ex. coll E. Olivier; Suppl. material 1: Fig. S2).

Olivier mentioned examining specimens in his and also in Oberthür’s collections. It is unclear how many specimens Olivier examined, and we did not have the opportunity to carefully look for them at the MNHN.

Brazil • Rio de Janeiro: Angra dos Reis: Parque Estadual da Ilha Grande), Pico do Papagaio; 4 ♂; 29 Jul. 2017; L. Silveira leg. (DZRJ) • 23°08'51.5"S, 44°10'52.4"W; 345 m a.s.l.; 1 ♂; Aug. 2017 (DZRJ) • 23°10'05.7"S, 44°11'04.0"W; 170 m a.s.l.; 1 ♂, Sep. 2017 (MNRJ) • same data as for preceding; 1 ♂, Apr. 2018 (MNRJ) • same data as for preceding, Estrada para Dois Rios; 2 ♂; 22 Nov. 2017 (MNRJ) • same data as for preceding; 2 ♂; Jul. 2018 (MNRJ) • same data as for preceding, Poço do Soldado; 23°10'04.7"S, 44°11'03.5"W; 160 m a.s.l.; 1 ♂; Dec. 2017 (DZRJ) • same data as for preceding; 1 ♂; Aug. 2017 (MNRJ) • same data as for preceding; 1 ♂; Jan. 2018 (MNRJ).