Tomarus amazonicus ( Arrow, 1914 ) López-García & Deloya, 2022

López-García, Margarita M. & Deloya, Cuauhtémoc, 2022, Cladistic analysis reveals polyphyly of Tomarus (Coleoptera: Scarabaeidae: Dynastinae): new classification and taxonomic revision, Zootaxa 5211 (1), pp. 1-119 : 55-56

Tomarus amazonicus ( Arrow, 1914) new status and combination

( Figs. 8G, K , 16B , 19B , 23A , 27B ; 42 )

Ligyrus amazonicus Arrow, 1914: 273 .

Female lectotype (BMNH) “ SYNTYPE // Ega / Braz. // Ligyrus ♀ / amazonicus Arr. / M.E. Bacchus det. 1970” here designated. Female paralectotype (BMNH) “ SYNTYPE // ♀ // Amazon / Bates // Fry Coll. / 19051100. // 19194 // Ligyrus / amazonicus Arr. / M.E. Bacchus det. 1970”. Female paralectotype (BMNH) “ SYNTYPE // Obydos. / Lower Amazon. / 2. II. 9– / E.E. Austen. / 96--80 // Ligyrus ♀ / amazonicus Arr. / M.E. Bacchus det. 1970”.

Description. Habitus as in Fig. 27B . Length 22.0–25.0 mm; humeral width 11.0– 12.5 mm. Color dark brown to black. Head: Frons and clypeus coarsely and densely rugose. Frontoclypeal region with 2 transverse tubercles separated by about 4.5 tubercle diameters. Clypeus narrowed towards apex, base 3 times wider than apex. Clypeal teeth triangular, separated by a tooth diameter. Mandible with 2 apical teeth and a lateral, narrowly rounded tooth. Mentum abruptly constricted at apical 3rd. Galea of maxilla with teeth 5 and 6 well developed. Interocular distance 3.5 times an eye width. Pronotum: Surface with small punctures, denser and deeper on anterior and posterior angles. Apical tubercle small, rounded. Subapical fovea shallow, narrow (1/3 as wide as interocular distance), equal in both sexes, surface transversely rugose. Scutellum: With minute, sparse punctures. Elytra: Punctures on first interval as large as those on other intervals. Inner surface of apex with rounded large tubercles forming 11–12 parallel lines ( Fig. 8K ). Abdomen: Apex of tergite IV with a triangular wide area with large, rounded tubercles forming 18 diagonal parallel lines ( Fig. 8G ). Pygidium with dense rugosity on basal 3rd; apex rounded. Venter: Apex of prosternal process flat, longitudinally oval to subrectangular. Metasternum with minute setae on anterior angles. Legs: Protibia tridentate, with a basal small denticle.Apex of metatibia crenulate, with 23–28 spinules. Male genitalia: Phallobase as long as parameres. Parameres with 1 dorsal tooth each side; tooth long, acute; apices roundly expanded ( Figs. 16B , 19B ). Internal sac with copulatory lamella and short lamellar spiny belt; with a complex of 8 spine-like accessory lamellae, without or with reduced granules at base ( Fig. 23A ).

Taxonomic remarks. This species was described by Arrow (1914) and then synonymized by Endrödi (1969) under T. gyas based on the approximate shape of the parameres and difficulty to delimitate the differences on the shape of pronotal fovea and protibia. Despite the convergence in the shape of parameres, the phylogenetic analysis evidenced that this species is not close to T. gyas , and they are different in several characters, such as the shape of the frontal tubercles, setation on the metasternum, the stridulatory apparatus, and the internal sac of the aedeagus. Therefore, T. amazonicus is treated here as a valid species and classified in the genus Tomarus .

Diagnosis. Tomarus amazonicus is recognized by the following character combination: frontoclypeal tubercles transverse; pronotal tubercle small and rounded ( Fig. 27B ); subapical fovea shallow, narrow (1/3 as wide as interocular distance), equal in both sexes; metasternum with minute setae on anterior angles; protibia tridentate and with an additional basal denticle; apex of metatibia with 23–28 spinules; parameres with a long, acute tooth on each side, apical half strongly contracted, apices roundly expanded ( Figs. 16B , 19B ).

Distribution. Amazon region of Brazil, Bolivia, Peru, Ecuador, and Colombia.

Locality records ( Fig. 42 ). 462 specimens examined from BMNH, CEIOC, CERPE, FSCA, IAvH, ICN, MEKRB, MN / UFRJ, MZUSP, SENASA, UNAB, UNSM, and USNM. Some records from CMNC and Endrödi (1969). BOLIVIA (11). Beni (10): Riberalta; Rurrenabaque; Trinidad; Vaca Diez. Buena Vista (1): Tacaraundi. BRAZIL (319). Acre (3): Cruzeiro do Sul; Porto Walter; Vila Fejo. Amazonas (118): Benjamin Constant; Boca do Rio Madeira; Borba; Coari; Codota’s; Curucuri; Guajará; Ipixuna, Rio Gregorio ; Itacoatiára; Lago Januaca; Manaus; Rio Japula ; Rio Liberdade , Estirao da Preta ; Rio Salimoes , entre Lago Jacaré e Purus; São Sebastian do Uatuma ; Tabatinga; Tefé (Ega). Pará (125): Boca do Lago de Terra Santa ; Ilha do Itanduba ; Maicurú; Obidos; Oriximiná; Paraná de Alenquer; Prainha; Rio Paru ; Santarém. Rondônia (73): Guapore; Porto Velho, Rio Madeira ; Samuel. Tocantins (1): Buriti do Tocantis , Assentamento Ouro Verde, Chacára da Bisa. No data (6). COLOMBIA (41). Amazonas (22): Leticia; Leticia (20 km N); Purité, San Juan. Caquetá (19): Florencia; Río Orteguaza near Río Peneya. ECUADOR (18). Napo (15): Jatun Sacha Biological Station ; Lago Agrio (18 km E); Misahualli Jungle Lodge. Imprecise data (3): Quito. PERU (72). Junín (1): Satipo, Huancayo. Loreto (55): Iquitos; Explorama Inn; Jungle Amazon Inn; Maynas; Yanamono. Huánuco (7): Marañón; Tingo María. Madre de Dios (6): Reserva Nacional Tambopata. Ucayali (1): Laguna Yarinacocha. No data (2). IMPRECISE DATA (2). Amazonas .

Natural history. This species is restricted to the Amazon rainforest between 300–1050 m. Some specimens were collected using light traps.

Figures

FIGURE 8. Stridulatory apparatus. A, D) Proculigyrus cicatricosus, B, E) Ligyrus (Ligyrus) burmeisteri, C, F) L. (Ligyrodes) relictus, G, K) Tomarus amazonicus, H, L) T. maimon, I, M) T. maternus, J, N) T. gyas.

FIGURE 16. Parameres in frontal view. A) Tomarus adoceteus, B) T. amazonicus, C) T. bituberculatus, D) T. colombianus, E) T. discrepans, F) T. gyas, G) T. laevicollis, H) T. laticaudus, I) T. maimon, J) T. maracaiboensis, K) T. maternus, L) T. pilcopataensis, M) T. pullus, N) T. pumilus, O) T. roigjunenti, P) T. rostratus, Q) T. selanderi, R) T. subtropicus.

FIGURE 19. Parameres in lateral view. A) Tomarus adoceteus, B) T. amazonicus, C) T. bituberculatus, D) T. colombianus, E) T. discrepans, F) T. gyas, G) T. laevicollis, H) T. laticaudus, I) T. maimon.

FIGURE 23. Internal sac. A) Tomarus amazonicus, B) T. discrepans, C) T. laticaudus, D) T. maimon. Abbreviations: AL: Accessory lamellae, CL: Copulatory lamella, LSB: Lamellar spiny belt, Ra: Raspula, SD: Sclerotized diverticulum.

FIGURE 27. Habitus of the species of Tomarus: A) Tomarus adoceteus, B) T. amazonicus, C) T. bituberculatus, D) T. colombianus, E) T. discrepans, F) T. gyas, G) T. laevicollis, H) T. laticaudus, I) T. maimon. Scale bar: 5 mm.

FIGURE 42. Distributional records of Tomarus gyas and T. amazonicus.