Triarius novoleonis Clark and Anderson, 2019

Clark, Shawn M. & Anderson, E. Russell, 2019, A Review of Triarius Jacoby, 1887 (Coleoptera: Chrysomelidae: Galerucinae: Luperini), with Descriptions of a New Genus and Four New Species, The Coleopterists Bulletin 73 (2), pp. 343-357 : 353-354

Triarius novoleonis Clark and Anderson , new species

Zoobank.org/ urn:lsid:zoobank.org:act:0AD00673-3C8D-4307-8AF3-0C8F0C9349FB Figs. 2i , 3g

Diagnosis. The tarsal claws of this species are appendiculate, the head is yellow, and the metasternum is black. The elytra are yellow, except for a narrow, dark brown sutural stripe, and, in some specimens, dark lateral stripes ( Fig. 2i ). This combination of characters distinguishes this species from all others of the genus Triarius . The aedeagus is also distinctive, being bisinuate in lateral view, as well as narrowed near the distal fourth in dorsal view ( Fig. 3g ).

Description of Holotype. Form elongate oval ( Fig. 2i ); body 6.1 mm long, 2.1 mm wide. Head orange-yellow, with darker posterior markings; pronotum yellow with vague darker maculae; scutellum black; elytra yellow, with narrow sutural stripe; ventral areas largely black; legs bicolored.

Head with dark markings on anterior corners of frontal tubercles, clypeus, and mouthparts; interocular distance subequal to 2/3 head width across eyes; posterior area of vertex smooth, shiny, largely impunctate; anterior portion of vertex near frontal tubercles glabrous, with punctation noticeably strigose; each frontal tubercle glabrous, impunctate, subtriangular, about twice as wide as long, with acute extension at anterior angle mesad of antennal fossa, narrowly contiguous with other frontal tubercle at posteromesal angle, delimited laterad by shallow depression, delimited posteriad by abrupt depression; mesal frontal ridge narrow, but not sharply carinate; antennal fossae separated from each other by distance slightly greater than fossal diameter; raised area of clypeus strongly transverse, about as wide as distance between eyes, about as long as width of antennomere 1, covered posteriad with numerous long setae; distal portion of clypeus very thin, covering posterior portion of labrum; area of head posterolaterad of eyes with numerous long, white setae; area immediately posteromesad of each eye with single long, white seta; genae short, length subequal to width of antennomere 2, densely covered with short, white setae. Eyes oval, 1.5 times as long as broad, finely facetted. Labrum yellow, narrowly darker distally, subtrapezoidal, much broader than long, narrower distad than basad, basal width slightly less than distance between lateral margins of antennal fossae; mandibles mostly yellow, distal portion piceous; maxillary and labial palpi dark brown. Antennae nearly filiform, extending to middle of elytra, densely setose, with longer setae near apex of most antennomeres; basal 3 antennomeres orange-yellow; distal 8 antennomeres black; antennomere 1 slightly curved, shiny, much longer than broad, nearly as long as antennomeres 2 and 3 combined; antennomere 2 slightly more than half as wide and about 1/3 as long as antennomere 1; antennomere 3 distinctly longer than 2, nearly twice as broad apicad as basad; antennomeres 4–10 each nearly as long and broad as antennomere 1, each slightly broader distad than basad; antennomeres 9–11 distinctly flattened; antennomere 11 subequal in length to antennomere 10, distinctly narrowed towards apex.

Pronotum with 1 mesal and 2 lateral, large, poorly defined, slightly darker areas; shape transversely arched, indistinctly and very shallowly depressed on each side of meson, widest near anterior third, basal width subequal to head width; surface glabrous, minutely punctate, shiny; setose tubercle present at each anterior and posterior corner; lateral margins strongly carinate, equipped with several short setae; anterior margin lacking carina, with dense row of short setae; posterior margin with narrow carina. Scutellum equilaterally triangular, glabrous, impunctate, shiny.

Elytra 4.8 mm long, together slightly wider than prothorax, 3.6 times as long as pronotum, 0.8 times as long as entire body. Humeri well-developed; basal calli weakly developed, not delimited behind by depression; distinct discal and sublateral costae absent. Discal surface finely punctate, with punctures slightly larger than those on pronotum; interpunctural areas shiny; pubescence largely absent, but sparsely scattered setae present, mostly on distal half. Epipleura broad at base, distinctly narrowed before middle of elytron, absent in distal part of elytron.

Body beneath black, except prothorax yellow. Ventral areas of prothorax mostly glabrous, shiny; anterior margin lined with fringe of long setae; posterior margin lined with fringe of shorter setae; prosternum anterior to coxae short, length subequal to maximum diameter of antennomere 1; procoxal cavities open behind. Mesothorax shiny, glabrous. Metathorax densely covered with white pubescence throughout. Abdomen densely covered with white pubescence; terminal ventrite with strong mesal impression in basal half, with large rectangular lobe at apex; terminal tergite black, not visible beyond elytra, densely pubescent and punctate. Legs largely covered by dense, white pubescence; anterior coxae and trochanters black, middle coxae and trochanters orange-brown; hind coxae black; hind trochanters orange-brown; front and middle femora orangebrown; hind femora orange-brown in basal half, nearly black in distal half; tibia and tarsi dark brown to nearly black; front legs with basal tarsomere slightly widened, about as broad as tibial apex; tarsal claws appendiculate.

Aedeagus symmetrical in dorsal view, strongly sinuate in lateral view. Distal portion distinctly widened in dorsal view ( Fig. 3g ).

Variation. Not all specimens have the vaguely darker maculae that are present on the head and pronotum of the holotype. Additionally, in some specimens, the mesothorax and abdomen are yellow, rather than black.Females measure 6.2–7.3 mm in length; the basal tarsomere of each front leg is narrower; and the rectangular lobe at the abdominal apex is lacking.

Holotype. “ MEXICO: Nuevo Leon / 7 mi. s. La Escondida / July 4, 1973 / Mastro & Schaffner” (male, TAMU).

Paratypes. Same data as holotype. (1 female, BYU; 4 females, TAMU; 1 female, originally from TAMU but gifted to UNAM) .

Etymology. The species epithet is composed of the Latin roots “ novo ” (meaning new) and “ leonis ” (meaning lion). It refers to the Mexican state where the beetles were collected.

Comments. As noted in the Variation section above, the ventral coloration is variable. Even so, we are confident that all of the six examined specimens belong to a single species.

Figures

Fig. 2. Triarius species, dorsal habitus. A) T. pini, male, B) T. pini, female, C) T. trivittatus, D) T. nigroflavus, male, E) T. nigroflavus, female, F) T. melanolomatus, G) T. lividus, H) T. texanus, I) T. novoleonis.

Fig. 3. Triarius species, aedeagi, dorsal and lateral views. A) T. pini, B) T. nigroflavus, C) T. melanolomatus, D) T. lividus, E) T. trivittatus, F) T. texanus, G) T. novoleonis.