Quadrus (Ebona), Zhang & Cong & Shen & Song & Grishin, 2023

Zhang, Jing, Cong, Qian, Shen, Jinhui, Song, Leina & Grishin, Nick V., 2023, Genomics-based taxonomic rearrangement of Achlyodini and Carcharodini (Lepidoptera: Hesperiidae: Pyrginae), Insecta Mundi 2023 (16), pp. 1-33 : 8

Ebona Grishin , new subgenus

http://zoobank.org/ 8A1637CD-1681-42BC-AE8A-04FF28148C42

Type species. Quadrus eboneus E. Bell, 1947 .

Definition. The newly expanded genus Quadrus Lindsey, 1925 (type species Papilio cerialis Stoll, 1782 ) can be divided into eight clades at the subgenus level in the tree ( Fig. 1 ). In addition to the nominotypical subgenus, two of these clades correspond to traditional subgenera, previously treated as genera: Ouleus Lindsey, 1925 (type species Achlyodes fridericus Geyer, 1832 ) and Zera Evans, 1953 (type species Achlyodes zera Butler, 1870 ), and five clades represent new subgenera. One of these new subgenera brings together species dispersed among three genera ( Ouleus , Zera , and Pythonides ). It keys to E.37.3a in Evans (1953) and is distinguished from its relatives by mostly dark wings without blue, hind-tibiae with one pair of spurs, tapered to a point uncus tip, and stout ampulla process. In DNA, a combination of the following base nuclear genomic pairs is diagnostic: aly770.31.1:C235A, aly770.31.1:A588G, aly6311.5.2:A42G, aly6311.5.2:A60G, aly 1370.7.2:T139G.

Etymology. The name is a feminine noun in the nominative singular, given for the dark appearance of these species, with “o” to derive from the type species name and to avoid homonymy with Ebena Schumacher, 1817 (in Mollusca); from the genus Ebenus , commonly known as ebony plants. Ebony wood is known for its dark, brown, and often nearly black colors.

Species included. Pythonides juxta Bell, 1934 , Quadrus eboneus E. Bell, 1947 , Ouleus negrus Nicolay, 1980 , Ouleus negrus cristatus Steinhauser, 1989 (see below), and Pythonides pescada Bell, 1956 .

Parent taxon. Genus Quadrus Lindsey, 1925 .

Quadrus (Ebona) cristatus (Steinhauser, 1989) is a species distinct from Quadrus (Ebona) negrus (Nicolay, 1980)

The genomic tree reveals that the holotype of Ouleus negrus cristatus Steinhauser, 1989 (type locality Colombia: Valle del Cauca, Rio Anchicayá, sequenced as NVG-15038D08, GenBank barcode OR665721) and a topotypical paratype of Ouleus negrus Nicolay, 1980 (type locality Panama: Veraguas Prov., Santa Fe, sequenced as NVG-19076D07, GenBank barcode OR665722) are not monophyletic and belong to different, albeit closely related, clades in the subgenus Ebona new subgenus of Quadrus Lindsey, 1925 (type species Papilio cerialis Stoll, 1782 ) ( Fig. 1 ). Furthermore, they are genetically differentiated from each other, e.g., COI barcode difference of 4.3% (28 bp). Therefore, we propose that Quadrus (Ebona) cristatus (Steinhauser, 1989) , new status, is a species distinct from Quadrus (Ebona) negrus (Nicolay, 1980) . We note that Q. cristatus is closely related to (conspecific with?) Pythonides pescada E. Bell, 1956 (type locality in Ecuador: Río Pescado) ( Fig. 1 ) and is phenotypically similar to it in having a distal part of ventral hindwing white. However, O. negrus is closely related to (but distinct from!) Zera eboneus E. Bell, 1947 (type locality in Mexico: Veracruz) and is phenotypically similar to it in largely uniform dark-brown, unspotted appearance on both sides of wings. These close relationships were overlooked, likely because species in the two pairs were incorrectly placed in different genera before ( Ouleus and Pythonides , and Ouleus and Zera ). If they were classified correctly, each pair’s more recently proposed species might have never been described due to phenotypic similarities with its previously named counterpart. Analysis of additional specimens, including their genomic sequencing, may lead to conclusion that Q. pescada and Q. cristatus are conspecific because they are more similar to each other genetically (0.3%, 2 bp COI barcode difference) than O. eboneus to O. negrus , the latter pair being sufficiently different from each other for us to be confident about their specie-level status (COI barcode difference of 2.6%, 17 bp).

Figures

Figure 1. The nuclear genome-based phylogeny of Achlyodini (continued in Fig. 3). Only the segment of the tree corresponding to the subtribe Pythonidina is shown. The bottom segment of the tree (subtribe Achlyodinia) is replaced with four dots and is shown in Fig. 3. The tree is constructed from protein-coding regions in autosomes. The tree is rooted with Carcharodus alceae (NVG-18087F02, GenBank barcode OR665734), not displayed. Statistical support values are shown by nodes. For each specimen, its name adopted in this work is given first, and a previously used name is listed in square brackets (if different), supplemented with the DNA sample number, type status (HT holotype, LT lectotype, ST syntype, T type, PT paratype, and PLT paralectotype), general locality and collection year (“old” means collection year known, but likely before 1950, mostly around the turn of 20th century). See Table S1 in the Supplemental file (Zhang et al. 2023d) for additional data about these specimens. Synonyms are given in parentheses preceded by “=”. The type status refers to this synonym if the synonym name is provided. Names of genera (larger font, more prominent tree branches, on the left) and subgenera (smaller font, less prominent tree branches, on the right) are shown by the clades corresponding to these taxa. New genus-group names are highlighted in yellow. Branches leading to the type species (or their closest sequenced relatives) of valid genus-group names are marked with large black dots and refer to the subgenus (in parenthesis) given in the corresponding name, or the genus if the subgenus is not specified. The same notations are used in Fig. 3–6. Names of taxa that before this work were placed in genera Pythonides (red), Gindanes (cyan), Quadrus (green), Ouleus (blue), and Zera (purple) are shown in color to illustrate rampant violations of monophyly in these taxa, corrected here.