Psyrassa tysoni, Bezark & Santos-Silva, 2023

Bezark, Larry G. & Santos-Silva, Antonio, 2023, Expanding knowledge of American Cerambycidae (Coleoptera): new species, new records, and morphological variations, Papéis Avulsos de Zoologia 63, pp. 1-19 : 5-8

Psyrassa tysoni sp. nov. ( Fig. 2 A-F)

Description: Holotype female: Head capsule dark reddish brown with irregular dark brown areas; ventral mouthparts mostly brown, except brownish maxillary and labial palpomere I and light yellowish-brown remaining palpomeres; antennae light yellowish brown. Prothorax dark reddish brown, except dark brown anterior margin and with irregular areas. Ventral surface of meso- and metathorax mostly brown, lighter than on prothorax. Scutellum dark brown close to margins, light brown anterocentrally.Elytra dark orangish brown basally,gradually lighter toward apex on remaining surface.Abdominal ventrites mostly dark orangish brown. Legs yellowish brown.

Head: Frontal plate ( Fig. 2D ) longer than basal diameter of scape, smooth, glabrous; remaining surface of frons abundantly, coarsely punctate centrally, punctures finer close to genae; nearly all punctures with a short white seta. Area between antennal tubercles and upper eye lobes abundantly, coarsely punctate, punctures with short whitish seta; with narrow well-marked sulcus close to eyes; remaining surface of vertex glabrous, transversely, somewhat shallowly reticulate-punctate close to prothorax, subsmooth anteriorly. Antennal tubercles smooth, glabrous, except posterior region with a few somewhat fine punctures with short white seta. Area behind upper eye lobes partially smooth close to eye, transversely, somewhat shallowly reticulate-punctate on remaining surface; with one long, erect yellowish seta superiorly close to eye, and a few short, erect yellowish setae near eye. Area behind lower eye lobes smooth, glabrous. Genae proportionally long ( Fig. 2E ), with the anterior margin of lower eye lobes distinctly away from the anterior margin of the gena; abundantly, somewhat coarsely punctate, except smooth apex; punctures with short, decumbent yellowish seta. Maxillary palpomere IV and labial palpomere III elongate, gradually widened from base to apex. Median groove distinct from clypeus to area between upper eye lobes. Wide central area of postclypeus coarsely, confluently punctate; with a few short whitish setae, and one long, erect yellowish seta on each side. Sides of postclypeus smooth, glabrous. Labrum somewhat sparsely, coarsely punctate posterocentrally, abundantly somewhat coarsely punctate centrally near anterior margin,smooth on remaining surface; with sparse, somewhat short yellowish setae on posterior punctate area, tuft of long, erect yellowish-brown setae on sides of anterior half, and dense, somewhat short, yellowish-brown setae on anterior punctate area. Gulamentum ( Fig. 2B ) smooth, glabrous on posteri- or half; anterior half sparsely, coarsely punctate, sulcate close to eyes, punctures with long, erect yellowish seta, and sulcate area with sparse, short, erect yellowish-white setae. Outer side of mandibles densely, coarsely punctate on basal ¾, smooth on apical quarter; with sparse, somewhat long, decumbent yellowish setae on basal ¾, except long, erect, thick yellowish-brown seta close to smooth area, glabrous on apical quarter. Upper eye lobes with four rows of ommatidia (only two or three apically); distance between upper eye lobes 0.29 times distance between outer margins of eyes; in frontal view, distance between lower eye lobes 0.50 times distance between outer margins of eyes. Antennae 1.55 times elytral length, reaching elytral apex at posterior quarter of antennomere X. Scape sparsely, finely punctate; with sparse, short, decumbent yellowish-white setae, slightly more abundant basally, and long, erect setae of same color interspersed. Pedicel sparsely, finely punctate, with sparse, short, decumbent yellowish-white setae and long, erect setae of same color interspersed; antennomeres with somewhat abundant, decumbent white pubescence not obscuring integument, pubescence dens- er from V; III-IX with long, erect yellow setae ventrally, setae sparser and shorter on VII, and present only apically on VIII-IX; dorsal apex of III-VIII with a few long, erect yellowish setae; antennomeres III-IV not carinate dorsally; inner apex of antennomere III with spine 2.6 times pedicel length, with blunt apex; inner apex of antennomere IV with spine 1.4 times pedicel length, with acute apex; inner apex of antennomere V with spine 0.7 times pedicel length, with acute apex; inner apex of antennomeres VI-VIII without spine. Antennal formula (ratio) based on length of antennomere III (excluding spines): scape = 0.96; pedicel = 0.19; IV = 1.07; V = 1.19; VI = 1.21; VII = 1.15; VIII = 1.11; IX = 1.07; X = 1.05; XI = 1.19.

Thorax: Prothorax distinctly longer than wide, subparallel-sided; anterior and posterior constrictions moderately well marked. Pronotum ( Fig. 2A ) somewhat sparsely, coarsely punctate, except some areas smooth or almost smooth; nearly all punctures with erect,short or long yellowish seta. Sides of prothorax ( Fig. 2E ) sparsely, coarsely punctate, except smooth area close to procoxal cavity; punctures with long, erect yellowish seta. Posterior half of prosternum somewhat abundantly, coarsely punctate, posterocentral region transversely rugose, with abundant white pubescence not obscuring integument, and long, erect pale-yellow setae interspersed, pubescence absent laterally; anterior half somewhat transversely rugose, sparsely, coarsely punctate, punctures with long, erect pale-yellow seta, except area close to anterior margin finely, transversely rugose with fine punctures interspersed. Procoxal cavities open posteriorly ( Fig. 2F ). Prosternal process with abundant white pubescence not obscuring integument, pubescence sparser apically, and a few long, erect pale-yellow setae interspersed on basal half; narrowest area 0.27 times procoxal width. Mesoventrite with sparse yellowish-white pubescence anterocentrally, pubescence distinctly dens- er laterally and whiter, more abundant centrally close to mesoventral process; area close to mesoventral process sparsely, coarsely punctate, remaining surface sparser and finely punctate; punctures with long, erect pale-yellow setae, more distinctly close to mesoventral process. Mesanepisternum and mesepimeron with abundant yellowish pubescence partially obscuring integument. Mesoventral process gradually narrowed from base to middle, then distinctly widened toward apex;with somewhat abundant whitish pubescence on basal half, almost absent on posterior half; with long, erect pale-yellow setae interspersed on basal half; narrowest area 0.48 times mesocoxal width. Metanepisternum with moderately abundant yellowish-white pubescence not obscuring integument. Metaventrite sparsely, coarsely punctate, except smooth area close to metathoracic discrimen; sides of anterior half with somewhat abundant grayish-white pubescence not obscuring integument;sides of posterior half with dense grayish-white pubescence (more yellowish-white depending on light source);wide central region glabrous and punctures with long, erect yellowish-white seta. Scutellum with abundant white pubescence, distinctly denser close to margins on posterior half. Elytra: Abundantly, coarsely punctate on anterior half, punctures gradually finer and sparser toward apex on posteri- or half; some punctures with long, erect pale-yellow seta; apex truncate, slightly concave centrally, with long spine on outer angle and short triangular projection on sutural angle. Legs: Femora sparsely, finely punctate; with sparse, long, erect pale-yellow setae, more abundant on base of ventral surface, and a few short, decumbent setae of same color interspersed. Protibiae with dense, bristly yellowish-brown pubescence ventrally, apical ¾ of lateral surfaces,and apical third of dorsal surface; with long, erect yellowish-brown setae interspersed on pubescent area.Meso- and metatibia dense,bristly yellowish-brown pubescence on apical third of ventral surface, and long, erect yellowish-brown setae throughout,more abundant ventrally. Metatarsomere I about as long as II-III together.

Abdomen: Ventrites ( Fig. 2B ) moderately sparsely and finely punctate, except smooth apex of ventrites 1-4; with sparse, both short and long yellowish-brown setae, absent on apex of ventrites 1-4; apex of ventrite 5 slightly rounded.

Dimensions in mm: Total length, 12.25; prothoracic length, 2.20; anterior prothoracic width, 1.35; posteri- or prothoracic width, 1.45; maximum prothoracic width, 1.55; humeral width, 2.15; elytral length, 8.10.

Type material: Holotype female from GUATEMALA, Suchitepequez: 11 km N Patulul , 1,100 m, light trap, 14°32.213′N, 91°08.911′W, 06.vi.2013, E. Fuller leg. ( CASC, formerly WHTC).

Etymology: This species is dedicated to Bill Tyson, friend of the first author and collector of many interesting Cerambycidae through the years, who provided the holotype for examination.

Remarks: Psyrassa tysoni sp. nov. is similar to P.pertenuis (Casey, 1924) ( Fig. 2 G-2J) but differs as follows: frontal plate longer than basal diameter of the scape ( Fig. 2D ); distance between upper eye lobes 2.5 times basal diameter of the scape, distinctly shorter than twice maximum diameter of the scape ( Fig. 2A ). In P. pertenuis , the frontal plate is distinctly shorter than basal diameter of the scape ( Fig. 2I ), and the distance between upper eye lobes is equal to 3.0 times the basal diameter of the scape, distinctly wider than twice maximum diameter of the scape ( Fig. 2 H-2I).

The key by Toledo (2005) encompasses a problem in the alternative of couplet 2, which includes the species with wide genae (translated): "last segment of the maxillary palpi elongate to slightly broadened apically,″ leading to alternative of couplet 3; "last segment of the maxillary palpi campaniform,″ leading to the alternative of couplet 5. Actuality, the palpi of females included from the alternative of couplet 5 do not have the maxillary palpomere IV campaniform; they are simply elongate in females of P. graciliatra Toledo, 2005 , P. tympanophora Bates, 1885 , P. angelicae Toledo, 2005 , P. cerina Toledo, 2005 , P. proxima Toledo, 2005 , and P. clavigera Toledo, 2005 . In fact, only males of this group have the maxillary palpomere campaniform (see Toledo, 2005). Therefore, we are including the new species in the both options of the alternative of couplet 2 from Toledo (2005). Following the first option, the new species can be included in the alternative of couplet 4 modified:

4(3). Apex of the spine of the antennomere III acute. Mexico (Guerrero, Jalisco, Querétaro, Quintana Roo, Veracruz, Yucatán) .................... ............................................................. P.cribricollis (Bates,1885)

— Apex of the spine of the antennomere III blunt ..............................4′

4′(4). Distance between upper eye lobes 2.5 times basal diameter of the scape, distinctly shorter than twice maximum diameter of the scape ( Fig.2D ). Guatemala................................ P.tysoni sp.nov.

— Distance between upper eye lobes is equal to 3.0 times the basal diameter of the scape, distinctly wider than twice maximum diameter of the scape ( Fig. 2I ). United States of America (Alabama, Arkansas, Florida, Maryland, Mississippi, New Jersey, Louisiana, New York, North Carolina, Pennsylvania, South Carolina, Tennessee, Texas, Virginia, Washington D.C................................... .............................................................. P.pertenuis (Casey,1924)

Following the second option, the new species can be included in the alternative of couplet 5 modified:

5(2). Procoxal cavities open posteriorly...................................................5′

— Procoxal cavities closed posteriorly.................................................6

5′(5). Integument mostly blackish; apex of the spine of the antennomere III acute. Honduras........................... P.graciliatra Toledo,2005

— Integument most brown; apex of the spine of the antennomere III blunt. Guatemala............................................... P.tysoni sp.nov.

Figures

Figure 2. Psyrassa spp.(A-F) P.tysoni sp. nov., holotype female:(A) Dorsal habitus;(B)Ventral habitus;(C) Lateral habitus; (D) Head,frontal view;(E) Head,lateral view; (F) Procoxal cavities. (G-J) P.pertenuis (Casey,1924), holotype: (G) Lateroventral view; (H) Dorsal habitus; (I) Head, frontal view;(J) Partial lateral habitus. Figures G,I, and J byEugenio H.Nearns;figure H from Lingafelter et al.(2023).