Holonotus latithorax Thomson, 1861

Santos-Silva, Antonio, Nascimento, Francisco E. De L. & Kozlov, Anton Olegovich, 2019, The megadiverse fauna of Neotropical Cerambycidae (Coleoptera): Notes, descriptions, new records, new species, and revalidations, Zootaxa 4603 (3), pp. 441-472 : 442-445

Holonotus latithorax Thomson, 1861 , revalidated

( Figures 8–16 )

Holonotus latithorax Thomson, 1861: 305 ; 1864: 276; Lacordaire, 1868: 185; Gemminger, 1872: 2784 (cat.); Thomson, 1878: 4 (type); Bates, 1879: 13 (distr.); 1884: 238.

Derancistrus (Holonotus) latithorax ; Lameere, 1909: 12; 1913: 50 (cat.); 1919: 97; Blackwelder, 1946: 554 (checklist); Chemsak et al., 1992: 18 (cat.); Galileo & Martins, 1993: 208 (syn.); Noguera & Chemsak, 1996: 396 (cat.).

White (1853) described Solenoptera laevithorax based in a series of specimens (at least two syntypes male) from Guatemala (recorded as “Guatimala”). According to him: “Elytra… apex blunt, minutely serrated, end of margin toothed.” Examination of photograph of two male syntypes ( Fig. 7 ) allows seeing that the specimen at right side has the elytral apex really as described by White (1853). However, the resolution of the photograph does not allow confirming if the specimen at the left side has the elytral apex really serrated.

Some years later, Thomson (1861) described Holonotus , and confusedly described H. latithorax from Mexico, based on a couple, apparently, suggesting that he was not sure if the new species is or not equal to H. laevithorax : “Espèce: H. latithorax, White. — H. laevithorax, White, Cat. Long., B. M. , p. 54. Guatimala;” and, “169. HOLONO- TUS LATITHORAX. White?” However, Thomson (1864) accepted H. latithorax as a different species described in Thomson (1861), and designated it as the type species of the genus. Bates (1884) was the first who figured H. laevithorax and H. latithorax and, in our opinion, his interpretation was correct.

Lameere (1909) considered Holonotus as a subgenus of Derancistrus Audinet-Serville, 1832 , and synonymized Holonotus minor Bates, 1884 with H. laevithorax . Holonotus laevithorax and H. latithorax were separated in his key as follows (translated): “Mesosternum less elevated than prosternum; prothorax parallel-sided; meso- and metathoracic epimera covered with white pubescence”, leading to D. latithorax (= H. latithorax ); “Mesosternum more elevated than prosternum; prothorax not parallel-sided; epimera glabrous”, leading to D. laevithorax (= H. laevithorax ) and other species.

Galileo & Martins (1993) correctly pointed out (translated): “After the description of the genus Holonotus, Thomson (1860: 305) cited: “Espèce: H. latithorax, White. — H. laevithorax, White, Cat. Long. B.M. p. 54. Guatimala.” This citation is difficult to understand because there is no species described by White with the name latithorax . As it is indicated that Holonotus includes a single species (“espèce” and not “espèces”), we can suppose that Thomson considered H. latithorax White (nom. nud.) synonymous of H. laevithorax White. Subsequently, Thomson (l.c.) describe or redescribe a species under the following title: “169. HOLONOTUS LATITHORAX . White?” Again, this name appears with the name given to White. The type locality is Mexico. In 1864, Thomson (p. 276) indicates for type species of Holonotus , H. latithorax Thomson , …, Mexico. It was thus determined as a type species, whose author is Thomson and not White, published in 1860.” In the same work, they synonymized H. latithorax with H. laevithorax , considering the differences between them as just variations.

Curiously, neither Lameere (1909) nor Galileo & Martins (1993) saw the most conspicuous difference between H. laevithorax and H. latithorax . In the former, the elytral apex has a spicule laterally ( Fig. 17 ), and is finely serrated from this point toward sutural angle, while the latter does not have both of those features ( Fig. 16 ). Actually, Galileo & Martins (1993) defined the genus as having the spicule and finely serrated distal margin in both. However, those features are absent in H. latithorax .

As additional differences between H. laevithorax and H. latithorax , it is possible to list (feature in H. latithorax between parentheses): prothorax in both sexes strongly divergent from anterolateral angles to about midlength ( Figs. 1, 2, 4, 5, 7 ) (not or very slightly convergent after anterolateral angles ( Figs. 8, 11 , 12, 14 )); anterolateral angles of the prothorax narrow, acute in both sexes (wide, rounded); metatibiae in male shorter ( Fig. 3 ) (metatibiae longer ( Fig. 10 )); mesanepisternum and distal area of metanepisternum with pubescence nearly absent or sparse ( Figs. 2, 3, 5, 6 ), rarely slightly denser in both sexes (distinctly dense ( Figs. 9, 10 , 12, 13 ), rarely slightly less dense). Difference between the height of the prosternum and mesosternum recorded by Lameere (1909) is variable in both species. Accordingly, it is not a reliable feature separating the species. Although not a very reliable character (we have seen an exception), in general, the antennomere III in both sexes of H. latithorax is at most as long as the distance between the upper eye lobes; in H. laevithorax , they are always longer than the distance between the upper eye lobes.

Regarding the integument color, both, H. laevithorax and H. latithorax are variable. The elytra may be blackish basally, gradually becoming reddish-brown toward apex, or to be entirely blackish; and the femora may be partially reddish brown, or entirely black.

Based on those features, we are formally revalidating H. laevithorax , and designating the female syntype ( Fig. 14 ) as lectotype. We prefer do not chose the male syntype as lectotype, because, apparently, it is a teratological specimen (elytra noticeable reduced), and have the prothoracic shape as in male of H. laevithorax . The lectotype has the following labels ( Fig. 15 ):

1. White (bordered with green), handwritten: Latithorax / Type Thoms. / Mex.

2. White (bordered with black), handwritten: Holonotus / Thoms / E. 304

3. White (bordered with black), printed: Th. / TYPE

Figures

FIGURES 1–11. 1–7) Holonotus laevithorax: 1) Dorsal habitus, male; 2) Ventral habitus, male; 3) Lateral habitus, male; 4) Dorsal habitus, female; 5) Ventral habitus, female; 6) Lateral habitus, female; 7) Dorsal habitus, syntypes male. 8–11) Holonotus latithorax: 8) Dorsal habitus, male; 9) Ventral habitus, male; 10) Lateral habitus, male; 11) Dorsal habitus, female. Figure 7 by Jesus Santiago Moure (deceased).

FIGURES 12–21. 12–16) Holonotus latithorax: 12) Ventral habitus, female; 13) Lateral habitus, female; 14) Dorsal habitus, lectotype female; 15) Labels, lectotype female; 16) Elytral apex, male. 17) Holonotus laevithorax, elytral apex, male. 18–21) Lagocheirus plantaris plantaris: 18) Dorsal habitus, male; 19) Head and prothorax, male; 20) Dorsal habitus, female; 21) Head and prothorax, female. Figures 14–15 by Jiří Pirkl.