Sychnomerus Bates, 1885

Santos-Silva, Antonio, Botero, Juan Pablo & Wappes, James E., 2020, Neotropical Acanthoderini (Coleoptera, Cerambycidae, Lamiinae): Synonymies and new status in some genera, new species, transferences and new distributional records, Papéis Avulsos de Zoologia 60, pp. 1-40 : 2

Psapharochrus Thomson, 1864 , Scythropopsis Thomson, 1864 , Symperasmus Thomson, 1864 , and Sychnomerus Bates, 1885

The definitions of the above acanthoderine genera have seen numerous changes since their original descriptions. These changes have resulted in modifications in their status (some more than once) making for a complicated history. In the most part their original descriptions have not allowed taxonomists to clearly understand their limits, and as a result new species have been assigned to them that changed their limits. Thus, making the study of this group of genera even more complicat- ed and difficult. Santos-Silva & Nascimento (2018) commented about the differences between Acanthoderes and Psapharochrus , and reported: “Apart from those controversial classifications,it was Lacordaire (1872) who provided the best feature to separate Psapharochrus (including Symperasmus as a synonym) from Acanthoderes (Acanthoderes) and A. ( Scythropopsis ). The former was included among the genera with eyes coarsely or sub-coarsely granulated, while the two latter genera were included among those with eyes finely granulat- ed.” Lacordaire (1872) also included Aegomorphus in the group of genera with eyes coarsely granulated, and separated it from Psapharochrus in the key by the genal length (translated): “Genae very short, sometimes nearly absent”, leading to Aegomorphus ; and“Genae, at least, with medium size”, leading to Psapharochrus . However, the genae in the type species of Aegomorphus , Aegomorphus decipiens Haldeman, 1847 ( Figs. 4-6 ) (= Lamia modesta Gyllenhal, 1817 ( Figs. 41 ) = Aegomorphus modestus ), is distinctly long, as in the type species of Psapharochrus , Acanthoderes cylindricus Bates, 1861 ( Figs. 7-9 ). Actually, the genal length is longer in the type species of the former than in the latter, and Aegoschema sensu Lacordaire (1872) is equal to Aegoschema Aurivillius, 1923 . This becomes clear when seeing the species originally includ- ed in Aegomorphus by Lacordaire (1872): A. adspersus Thomson, 1861 ; A. moniliferus White, 1855 ; and A. obesus Bates, 1861 . But it is curious to note that Aegomorphus decipiens Haldeman, 1847 , type species of the genus, was included in Psapharochrus by Lacordaire (1872). The problem here was that Lacordaire (1872) wrongly attributed the authorship of the Aegomorphus to Thomson (1861), considering Aegomorphus Haldeman as a synonym of Psapharochrus . Evidently, thus occurred because Haldeman (1847) attributed the authorship of Aegomorphus to Dejean (1835) followed by a correction of this by Aurivillius (1923): “ Aegoschema n. nom. / Aegomorphus Thoms. (nec Hald. 1847).”

Santos-Silva & Nascimento (2018) summarized their conclusions as follows:“1. Symperasmus – probably a synonym of Psapharochrus , but, at least, it must be considered a subgenus of Psapharochrus . 2. Pardalisia – probably a synonym of Acanthoderes ; 3. Scythropopsis – probably a genus distinct from Acanthoderes ; 4. Eyes very finely granulated – Acanthoderes (Acanthoderes) ; A. (Pardalisia); A. ( Scythropopsis ). 5. Eyes coarsely or moderately coarsely granulated – Psapharochrus ; A. ( Symperasmus ).” However, at that time they did not formally propose any change in the status of those genera.

A study of the type species of Aegoschema and Psapharochrus has revealed that they share the same features and lack significant differences hence we conclude that they are not different genera. Accordingly, we formally synonymise Psapharochrus with Aegomorphus . Although, it is important to note that several species currently placed in Psapharochrus which have the lateral tubercles of the prothorax with the apex blunt (not acute as in the type species) and the elytra gradually narrowed from humerus to apex (not parallel-sided as in the type species), indicates that they are likely not true Psapharochrus and thus, not Aegomorphus either.

Figures

Figures 1-9. (1‑3) Acanthoderesdaviesii,male.(1) Dorsal habitus.(2) Head,frontal view.(3) Lower eye lobe.(4‑6) Aegomorphus modestus, female.(4) Dorsal habitus.(5) Head,frontal view.(6) Lower eye lobe.(7‑9) Aegomorphus cylindricus, male.(7) Dorsal habitus.(8) Head,frontalview.(9) Lower eye lobe.

Figures 35-42. (35‑39) Acanthoderes melanosticticus, (35) Syntype, dorsal view. (36) Pteridotelus contaminatus, holotype, dorsal habitus. (37) Male from Brazil (Santa Catarina), head, frontal view. (38) Idem, lower eye lobe. (39) Idem, protibia. (40) Psapharochrus contaminatus, holotype male, dorsal habitus. (41) Lamia modesta, holotype,dorsal habitus.(43) Pteridotelus lacrymans, holotype,dorsal habitus.