Memoan conani Campello, Vaz, Mermudes & Silveira, 2022

Campello, Lucas, Vaz, Stephanie, Mermudes, Jose R. M., Ferreira, Andre L. D. & Silveira, Luiz F. L., 2022, Comparative morphology and key to Amydetinae genera, with description of three new firefly species (Coleoptera, Lampyridae), ZooKeys 1114, pp. 131-166 : 131

Memoan conani Campello, Vaz, Mermudes & Silveira, 2022 sp. nov.

Figs 2 , 3 , 4 , 5 , 6 , 7 , 8

Etymology.

The specific epithet Memoan 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.

Diagnosis.

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 ).

Description.

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.

Biology.

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.

Remarks.

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.

Materials examined.

Holotype: Brazil • Rio de Janeiro: Rio de Janeiro: Parque Estadual da Pedra Branca, Núcleo Camorim, Trilha do Acude , 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) .

Figures

Figure 1. Distribution of new species of Amydetinae in the state of Rio de Janeiro, Brazil, in the southeastern Atlantic Forest.

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).

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).