Xela, Botero & Bezark & Santos-Silva, 2020

Botero, Juan Pablo, Bezark, Larry G. & Santos-Silva, Antonio, 2020, A new genus, new species and taxonomic notes on American Cerambycinae (Coleoptera, Cerambycidae), Zootaxa 4758 (1), pp. 157-175 : 163-164

Xela gen. nov.

( Figs. 11–15 )

Type species. Xela tysoni , here designated.

Etymology. Xelajú was the original Mayan name for the city currently known as Quetzaltenango, so named when the Spanish conquered the city (the name their native allies used). Today, many people still refer to it by the shortened version of its traditional name, Xela (pronounced “shay-la”). The genus name refers to the area where the type was collected.

Description. Body widened, flattened. Head nearly hypognathous. Frons transverse. Antennal tubercles widely separated, in frontal view, moderately elevated. Eyes divided, with single row of isolated ommatidia between lobes; distance between upper eye lobes wider than maximum width of one lobe; lower eye lobes about three times genal length. Antennae filiform, 11-segmented, much longer than body; scape, gradually widened toward apex, without apical projection; pedicel transverse; antennomere III shorter than IV. Prothorax wider than long, distinctly narrower than humeral width; with distinct lateral tubercles. Pronotum with moderately distinct gibbosities; with arched, transverse sulcus posteriorly. Prosternal process absent and mesoventral process represented as small projection of mesoventrite. Elytra somewhat rugose, distinctly widened toward apex, about seven times prothoracic length; integument soft; entirely covering abdomen; apex individually rounded. Femora almost fusiform. Protibiae arched, with posterior 2/3 of ventral surface flattened; meso- and metatibiae straight, cylindrical, distinctly longer than protibiae. Metatarsi about as long as half of length of metatibia; metatarsomere I about as long as II–III together. Male abdomen elongate, distinctly longer than meso- and metathorax together.

Remarks. Although it is not the scope of this work to address differences between tribes, it is necessary to make some comments on the differences between Methiini and Oemini, due to the tribal inclusion of the new genus.

According to Martins & Carvalho (1984), the last segment of the palpi in Methiini is subacuminate, the scape has no asperities, and the abdomen of the females has radular terminalia. On the other hand, still according to them, in Oemini the last segment of the palpi is subsecuriform, scape often with asperities, and abdomen of the females lacking radular terminalia. They included only five genera in Methiini : Methia Newman, 1842 ; Styloxus LeConte, 1873 ; Tessaropa Haldeman, 1847 ; Coleomethia Linsley, 1940 ; and Paratessaropa Zajciw, 1957 .

Philips & Ivie (1998) separated Methiini from Oemini as follows: “ Methiini are separated from the Oemini (and the Xystrocerini), by the subacuminate ultimate palpomeres, the usually reduced elytra, the medially confluent procoxae contacting each other medially, and the radular form of the female terminalia. Additionally, the Methiini are restricted to the New World.”

Later, Martins (1997) defined Methiini as follows (translated): “Metatibiae in male with narrow and longitudinal sulcus on inner surface; last ventrite in female with color of the integument contrasting with remaining segments, and apex emarginated and with row of short setae; head hypognathous; antennal tubercles not projected; maxillary palpi short; eyes with or without setae among ommatidia; scape and antennomere III, lacking asperities even in males; pronotal constrictions with same width; pronotum without distinct gibbosities; prosternal process absent; mesoventral process not emarginated at apex; elytra short, not covering membranous wings, with soft integument; mesonotum with or without sulcus; metathoracic discrimen not present along entire metaventrite; protibiae strongly curved, deeply sulcate.” Oemini (Oemina and Methiodina) was defined as not having a sulcus on the metatibiae of the male, scape and antennomere III with (Oemina) or without (Methiodina) asperities, basal constriction of the prothorax well-marked, and the last ventrite of females without modifications. The shape of the last segment of the palpi was not described for Oemina, but was defined as being acuminate toward the apex in Methiodina.

Apparently, all features pointed out to separate Methiini from Oemini are variable in the genera included in both tribes (especially the shape of the palpi, shape of procoxal cavities, and sculpturing of scape and antennomere III), with a single exception: the shape of the terminalia in females. Additionally, the sixth ventrite is exposed in males of Methiini , which never occurs in Oemina.

Xela gen. nov. differs markedly from all American Methiini genera by the elytra being distinctly widened toward apex, and entirely covering the abdomen. As pointed out by Philips & Ivie (1998), apparently, all non-American genera currently placed in Methiini belong to Oemini.

Figures

FIGURES 11–15. Xela tysoni, holotype male: 11) Dorsal habitus; 12) Ventral habitus; 13) Lateral habitus; 14) Head, frontal view; 15) Abdominal apex, ventral view.