Acanthoderes albolinitus Bates (1861) : 471

Silva Júnior, José O., Haseyama, Kirstern L. F. & Souza, Diego de S., 2021, Phylogenetic approach redefines Plistonax (Coleoptera, Cerambycidae, Lamiinae) with new combinations and a new genus of flat-faced long-horned beetles, Organisms Diversity & Evolution (New York, N. Y.) 21 (2), pp. 491-520 : 505-507

Acanthoderes albolinitus Bates (1861): 471 . Plistonax multipunctatus Thomson (1864): 19 ; Thomson (1878): 15 (type); Monné (2012): 79 (type).

Plistonax albolinitus Lacordaire (1872): 747 (syn); Zischka (1948): 8 (distr.); Lane (1960): 47 (comm., distr.); Monné and Magno (1992): 721, fig. 3 (distr., rev.); Monné (2005): 199 (cat); Martins et al. (2006): 270 (distr.); Morvan and Morati (2006): 37 (distr.); Giuglaris (2012): 63 (distr.); Morvan and Roguet (2013): 17 (distr.); Monné (2021) (cat).

Type locality: holotype (female) – Brazil, Amazonas , Tefé (Ega) ( MNHN) ( Fig. 10c ) .

Diagnosis. Males with tubercles on inner surface of antennomeres VI–XI ( Fig. 2e ). Pronotum with sparse white setae, with one pair of longitudinal black bands at level of median tubercles ( Fig. 8h, j ). Elytra with one pair of transversal black stains on median-basal region, located between crests and elytral suture ( Fig. 8h, j ).

Redescription. Male (♂) ( Figs. 8h–i , 10a ). General surface covered with decumbent light-brown setae, with distinct sparse white setae on frons, pronotum, antenna, legs, and elytra. Head. Large punctures. Gena subequal in length to lower ocular lobe. Antenna. Scape with two dorsal dark-brown stains. Pedicel about 1/3 length of scape; antennomere III about 1.3 length of scape; antennomere IV subequal to scape; remaining antennomeres decreasing gradually in length, except for antennomere XI, which is longer than X. Antennomeres V –XI each with one dark-brown stain near apex, covering antennomeres IX–XI almost entirely, and yellowish stains in remaining surface. Inner surface with distinct tubercles in antennomeres V –XI; distinct sparse erect setae on antennomeres I–VII; curly black setae on antennomeres IX– XI. Antenna reaching elytral apex at antennomere VIII .

Prothorax. Pronotum entirely covered by light-brown setae, except for one pair of longitudinal black bands at level of median tubercles; short lateral tubercle; median tubercles slightly elevated. Prosternal process with lateral margin distinctly convex. Mesothorax. Scutellum mostly covered by dark-brown setae, with distinct median-longitudinal yellowish band. Mesoventral process width smaller than diameter of mesocoxa; one pair of distinct tubercles on anterior region, slightly elevated. Elytra. Median-basal crest starting from base, reaching post-median region, curved and with small ridges on anterior region. White stain covering mid-basal region, narrowing along elytral surface, almost reaching apex; a black post-median Y-shaped stain; black stains on elytral slope, forming zigzag between margins and elytral suture; margin with dark-brown stains. Internal semierect seta in punctures white, short, and thick, strongly expanded towards apex, with sulci close to each other ( Fig. 8n ). Elytral apex rounded. Legs. Femora with dark-brown stains. Tibiae slightly expanded towards apex, with two dark-brown stains, intercalated by grayish stains. Tarsomerus I covered by white setae, tarsomeres II– V mainly with dark-brown setae. Abdomen. Covered with light-brown setae, except in dark-brown areas at lateral of segments I–IV. Male terminalia ( Fig. 11a, b, c, d, e, f ). Tegmen ( Fig. 11a ). Ringed part convex, with anterior region sclerotized in inner margin; remaining surface membranous; apex truncate, without reentrance. Paramere with uniform

Lac sclerotization, narrowed towards apex; basal region expanded laterally, with row of short setae; apex entirely covered with long setae; remaining surface with sparse and very short setae. Endophallus ( Fig. 11b–c ). Median lobe slightly curved in lateral view, with dorsal lobe indistinguishable; ventral lobe uniformly sclerotized; apex slightly narrowed, with deep median invagination. Median strut mostly membranous, with apex wrinkled and slightly sclerotized. Internal sac with one pair of sclerotized curved structures anteriorly. Ventral arc ( Fig. 11d ). Membranous, with stem slightly curved at apex, wider at base of stem and lateral projections. Tergites ( Fig. 11e–f ). Tergites VII and VIII wider than longer, both entirely sclerotized, covered with short setae at posterior region, with apex rounded. Tergite VII with base rounded, and tergite VIII with base straight, with membranous apophysis elongated.

Female (♀) ( Figs. 8j–k , 10c ). Differs from male in the following: inner surface of antenna without tubercles and curly black setae on antennomeres IX–XI; antenna reaching elytral apex at antennomere XI. Head ( Fig. 11g –j ). Labrum covered by short setae, with band of curly black setae at midposterior region ( Fig. 11g ). Mandible with outer surface transversal and inner surface without projections ( Fig. 11h ). Maxilla with cardo wider at base, with band of short setae at outer surface; stipes robust with long setae at apex; galea with distal portion oval, setose, narrowed towards base; lacinia elongated with short setae at center and long setae at outer surface; maxillary palpi II–IV gradually decreasing in width ( Fig. 11i ). Labium with prementum of rounded margin; ligula with a median deep reentrance at apex, with band of short setae at central portion, and longer setae at lateral and apex; labial palpus with segment I very short, segment II robust, and segment III elongated, slimmer than segment II ( Fig. 11j ). Prothorax. Proendosternite posteriorly orientated, with globose apex (Fig. 12a). Mesothorax (Fig. 12b, c). Mesoscutum with setae clustered at lateral region; stridulatory plate narrowed at anterior and posterior regions, with central region broader, occupying about 3/4 length of mesoscutum (Fig. 12b). Mesendosternite transversal, orientated to center-posterior region of mesothorax, reaching beyond mesocoxal cavity ( Fig. 12 c ). Metathorax (Fig. 12d, e). Metendosternite with one pair of lateral arms; lateral arm with superior portion wrinkled; one pair of tendons little protuberant; lamina with slight slope at lateral and slight uphill at center; stalk occupying about 1/3 length of general surface (Fig. 12d). Hind wing elongated; costa vein (C) short, occupying about 1/4 wing; Subcosta vein (Sc) slightly longer than C, fused to radial vein ( R). R well delimited, occupying about 3/5 of wing. Transverse vein radio-sector (r-s) short, connected to sector vein (S); transverse vein media-sector (m-s) longer than r-s, connected to anterior sector vein ( AS); the connection of these four veins (r-s, S, m-s, and AS) with R forming the radial cell. Media vein (M) divided in anterior media ( AM) and posterior media ( PM); MA near foldingwing area, oblique towards posterior region; MP vein near to center of wing, connected after half to cubitus vein (Cu). Cu well delimited, with length subequal to R, connected to latter at base through arcule (arc). Empulsal vein (E) originated at base of Cu, connected to 1st anal vein (1A), disconnected after half, where it disappears, resurfacing connected to plical vein (P); 2nd anal vein (2A) with origin jointed to 1A, with connection after half in 1A+2A. P starting about at half of Cu, fused to E posteriorly. E bifurcated in Ea, almost reaching outer membrane. Jugal vein (Ju) well delimited, with a slight curvature, occupying about 1/3 of width of wing (Fig. 12e) .

Variation. Dark-brown stains in antennomere III may be dorsally fused; the pattern of elytral stains may vary considerably; the Y-shaped stain may extend until margin of elytron, and the zigzag-shaped stain on elytral slope may be incomplete; elytral apex may be truncate.

Measurements (mm). Total length (15–19.7); elytral length (10.2–14.2); pronotum length (3.2–3.9); umeral width (5.8–7.6); pronotum width (5–6.6).

Distribution. Bolivia [Beni n.rec., Cochabamba], Brazil [Amapá, Amazonas, Pará], French Guiana (Fig. S4a).

Remarks. Bates (1861) described this species originally as Acanthoderes albolinitus , based on a single female specimen from the Ega region (currently Tefé, Amazonas, Brazil) ( Fig. 10c ). Thomson (1864) described Plistonax multipunctatus without detailing the type locality or how many specimens he examined. Lacordaire (1872) probably examined the types of A. albolinitus and P. multipuncatus (it is not clear in his work) and synonymized the two species in Plistonax albolinitus . We examined both type series and here determine that Thomson (1864) analyzed only one male specimen ( Fig. 10 a); thereby this is the holotype of P. multipunctatus . This species is similar to P. inopinatus , forming a well-supported clade in our phylogenetic analyses (Figs. 7, S2), but with some differences in the stains of the pronotum and elytra. Concerning the tubercles on the inner surface of the male antennomeres VI– XI, P. albolinitus frequently has more than one tubercle on each antennomere. This feature is rare in P. inopinatus . Additionally, the two species occur in different geographic regions, P. albolinitus in the Amazon region and P. inopinatus in the Atlantic forest.

Figures

Fig. 10 Holotypes of some species of Plistonax: a Plistonax multipunctatus Thomson, 1864 (=P. albolinitus). b Plistonax albituberculatus Silva Júnior & Souza, 2019. c Acanthoderes albolinitus Bates, 1861 (=P. albolinitus). d Plistonax antonkozlovi Santos-Silva, Nascimento & Silva Júnior, 2020. e Acanthoderes ariasi Chemsak & Hovore, 2002 (=P. ariasi comb. nov.). f Acanthoderes bialbomaculata Zajciw, 1964 (=P. bialbomaculatus). g P. senecauxi

Fig. 2 Character photographs: a 2:0 frons with small punctures (anterior view, Aegomorphus jaspideus). b 2:1 frons with large punctures (anterior view, A. travassosi). c 21:0 mesoventral process with antero-lateral tuber- cles slightly elevated (lateral view, Plistonax albolinitus). d 21:1 mesoventral process with antero-lateral tubercles very ele- vated (lateral view, Acanthoderes (Acanthoderes) daviesii). e 4:1 male’s antennomeres VI–XI with tubercles in the inner surface and 11:1 male’s antennomeres IX–XI with black setae in the inner sur- face (lateral view, male of P. albolinitus). f 6:1 antennomere III with darker stain near apex, 7:1 antennomere III with darker stain near base, 8:1 antennomere IV with darker stain near base, 9:0 antennomeres IV–XI with darker stain near apex in subapical posi- tion, and 10:1 antennomeres III– VII with erect setae in the inner surface (dorsal view, P. rafaeli). g 9:1 antennomeres IV–XI with darker stain near apex in apical position (dorsal view, P. insolitus). White dashed lines highlight the character states 2:0 and 2:1; blue arrows highlight the character states 6:1, 7:1, 8:1, 9:0, and 9:1; red arrows highlight the character state 10:1. Scale bars: 1 mm

Fig. 8 Miguelmonneus insolitus (a–f): a male’s dorsal habitus; b male’s ventral habitus; c female’s dorsal habitus; d female’s ventral habitus; e lateral habitus; f head (anterior view). Acanthoderes (Acanthoderes) daviesii: g head (anterior view). Plistonax albolinitus (h–n): h male’s dorsal habitus; i male’s ventral habitus; j female’s dorsal habitus; k female’s ventral habitus; l lateral habitus; m head (anterior view); n semierect seta of the elytral punctures, character state 28:0 (thick), micrograph (from left to right, base and apex; zoom 1300×). Scale bars: 5 mm, except figures f, g, m (1 mm), and n (25 μm)

Fig. 11 Plistonax albolinitus: male terminalia (a–f): a tegmen (ventral view); b endophallus (ventral view); c endophallus (lateral view); d ventral arc (ventral view); e tergite VII (dorsal view); f tergite VIII (dorsal view). Mouthparts (g–j): g labrum (dorsal view); h Mandible (dorsal view); i Maxilla (ventral view); j Labium (ventral view). Points and gray shapes represent sclerotized structures; roman numeral represents the segments of the maxillary and labial palpi.Car, cardo; Gal, galea; Lac, lacinia; Lig, ligula; Prem, prementum; Sti, stipes. Scale bars: 0.5 mm

Fig. 1 Character illustrations: a 1:0 male’s gena with margin curved (anterior view, Plistonax inopinatus). b 1:1 male’s gena with margin straight (anterior view, Aegomorphus jaspideus). c 3:0 scape slightly expanded to the mid-region (dorsal view, Ateralphus dejeani). d 3:1 scape strongly expanded in the mid-region (dorsal view, P. inopinatus). e 25:0 elytron with median-basal crest reaching no more than the half and 26:0 median-basal crest with anterior region straight (dorsal view, P. albituberculatus). f 25:1 elytron with median-basal crest reaching beyond the half and 26:1 median-basal crest with anterior region curved (dorsal view, P. inopinatus). g 19:0 prosternal process with lateral margin concave (ventral view, Steirastoma breve). h 19:1 prosternal process with lateral margin straight (ventral view, P. rafaeli). i 19:2 prosternal process with lateral margin convex (ventral view, P. inopinatus). Red arrows highlight the character states 1:0 and 1:1. Mbc, median-basal crest. Scale bars: 1 mm