A revision of Peltariosilis Wittmer (Coleoptera: Cantharidae), a surprisingly diverse Amazonian radiation Author Biffi, Gabriel Author Geiser, Michael text Papéis Avulsos de Zoologia 2020 Pap. Avulsos Zool., S. Paulo 2020-03-04 60 16 1 26 http://dx.doi.org/10.11606/1807-0205/2020.60.special-issue.16 journal article 10.11606/1807-0205/2020.60.special-issue.16 1807-0205 4984973 3C128243-07E3-4435-A496-D8F50F68389E Peltariosilis diversicollis sp. nov. ( Figs. 2 A-C, 5E, 10E, 12E, 13B, 14B, 15E-H) Type series: HOLOTYPE ♂ ( MPEG ): “ Rio CalÇoene / 2-8- 1961 // Brasil , AP / J. & B. Bechyné ” ( Fig. 5E ) . PARATYPES ( 2 specimens ):“Porto Platon / 21-7-1961 // Brasil , AP / J. & B. Bechyné ” ( 1 ♂ , MPEG ) ; “ R . CASSIPORÉ / Vila Velha / 14 / 15-9-1961 // Brasil , AP / J. & B. Bechyné // MZUSP 31232 ” ( 1 ♂ , MZUSP 31232 ) . Diagnosis: Pronotum with laterobasal lobe flattened, slit posteriorly into dorsal and posterior flaps with acute pointing projections posteriorly, and lateral unciform spine; dorsal projections flattened, broadly rounded, meeting dorsal edge of laterobasal lobe; sides of laterobasal lobes visible laterally, not concealed under dorsal projections. Scutellum with a short trapezoidal lamellar projection, wider than long, wide at base. Peltariosilis diversicollis sp. nov. differs from P.lamellata by the curved, unciform spines at the angles of laterobasal lobes, from P. major sp. nov. by the broad dorsal projections of pronotum, and from P.amapaensis , P.guyanensis and P.mensaemontis by the lateral sides of laterobasal lobes not concealed under dorsal projections. Description: Head entirely black; maxillae and labium light orange brown, slightly darker on distal palpomeres; antennae mostly dark brown, slightly lighter at dorsal surface of antennomeres IV-VIII; antennomeres I-II and apex of XI orangish to light brown; pronotum and scutellum light orange brown, slightly translucent; elytra dark brown, lighter at lateral margins; legs light orange brown, darker on the apex of tibiae and tarsi; thorax and abdomen dark brown, darker on last abdominal ventrite and tergite. Male: ( Fig. 5E ): Antennae short; antennomere I elongate, slightly wider apically, II short, cylindrical, III-IV nearly cylindrical, V-VIII flat at ventral surface and slightly globose at dorsal surface, IX-XI slender, filiform. Pronotum ( Fig. 10E ): anterior margin broadly arched, continuous with frontolateral lobes; frontolateral lobes broad, projected laterally; laterobasal lobes with one lateral unciform spine, flattened, slit posteriorly into dorsal and posterior flaps with acute pointing projections posteriorly; dorsal projections flattened, broadly rounded, meeting dorsal edge of laterobasal lobe. Scutellum ( Fig. 12E ) with a short trapezoidal lamellar projection, wider than long, wide at base, narrow at apex, distal margin notched. Elytra divergent at lateral margins, wider posteriorly; apex truncate. Abdominal tergite VIII ( Fig. 13B ) long and broad, lateral margins broadly rounded, wider medially; glandular pores not protruding; distal margin sinuous, with a small, shallow median notch.Ventrite VII ( Fig. 14B ) wide, lateral margins sinuous, broadly arched anteriorly, wider medially, constricted posteriorly; posterior margin arched; internal margins of median incision nearly parallel. Aedeagus ( Fig. 15 E-H): ventral plaque of tegmen lateroventral, shorter than internal sac and ventral sclerites, flattened laterally, wider medially, sinuous, broadly curved, apex acute and curved dorsally; parameres broadly fused at base and divergent towards apex, apex strongly curved dorsally, rounded with small acute tip; median lobe membranous, translucent; internal sac tubular, very elongate, straight, membranous, slightly sclerotised at apex; median dorsal sclerite absent; one pair of small, well-sclerotised lateral sclerites concealed behind parameres; paramedian dorsal sclerites elongated, nearly straight, broader at base and gradually narrowing at apex,apex acute; ventral sclerites very elongated,almost as long as internal sac, slender, straight, apex acute, divergent, slightly curved laterally. Figure 1. Head of Peltariosilis species , dorsal. (A) P. amapaensis ( Wittmer, 1966 ) ,male.(B) P.parviscutellaris sp.nov. ,female. Female: Unknown. Etymology: The epithet diversicollis is formed from the Latin words diversus (different) + collum (“neck”, prothorax), referring to the distinct shape of prothorax in this species. Distribution: Brazil ( Amapá state ) ( Fig. 18 ).