Trichiotes lightfooti Wirth & Smith, 2017

Wirth, Christopher C. & Smith, Aaron D., 2017, Review of the genus Trichiotes Casey (Coleoptera: Tenebrionidae: Pimeliinae: Edrotini), with the description of a new species and a preliminary checklist of the Tenebrionidae from Cuatrociénegas, Mexico, Zootaxa 4347 (3), pp. 533-542 : 535-538

Trichiotes lightfooti Wirth & Smith , sp. nov.

( Figs. 1 , 2 , 5 )

zoobank.org:act:98 A99692 -A56F-4F23-BEA3-464028934508

HOLOTYPE, (female) labeled ( Fig. 2 ): (a) “ Mexico: Coahuila, Cuatro / Cienegas Nat'l. Preserve / 20 IX 2011 / 26.84484°N 102.17866°W / D.C. Lightfoot et al., colrs”; (b) “ Site B 3 / ~ 19.43 km SW of Cuatro. / gyspum dunes, pedestals / general collecting”; (c) on blue paper “ Tenebrionid Base / Aaron D. Smith / Catalog # 16105”; (d) on red paper, “ HOLOTYPE / Trichiotes lightfooti / Wirth and Smith 2017 ” ( UNMC) .

PARATYPES (60 specimens) (all bearing the label “ PARATYPE / Trichiotes lightfooti / Wirth and Smith 2017 ” on yellow paper and the database label “Tenebrionid Base / Aaron D. Smith / Catalog # ” on blue paper, for convenience tenebrioniDBase catalog numbers are listed as TB # without quotations): Nine paratypes ( BMNH –2, CASC –7), labelled (a) “ MEX:Coah., 6mi. SW / Cuatros Cienegas / V-28-1981 J.Doyen / J.Liebherr”; (b) “on sand / at night”; (c) TB #s 16106–16107, 16899–16905. Two females ( EMEC), labelled (a) “ MEX:Coah., 9mi. SW / Cuatro Cienegas / V-29-1981 J.Doyen”; (b) “on dunes / at night”; (c) “Female reproductive / system removed / Slide#T20G 3V [1-2]”; (d) TB #s 16115–16116. Thirty-four paratypes ( CASC –7, EMEC –27), labelled (a) “ MEX:Coah., 9mi. SW / Cuatro Cienegas / V-29-1981 J.Doyen”; (b) “on dunes / at night”; (c) TB #s 16906–16912, 16135–16144, 16915–16931. Four paratypes ( EMEC), labelled (a) “ MEX: COAHUILA Rte.30 / 9 mi.s.s.w.

Cuatro- / cienegas el.2200' / 28-29 May 1981 / J.K. Liebherr / nr. gypsum dunes”; (b) TB #s 16145–16148. Eleven paratypes ( CASC –1, EMEC –10), labelled (a) “ MEX:Coah., 9mi. SW / Cuatro CienegasV / 28/29-1981 2200' / J.K.Liebherr ”; (b) “nr.gypsum / dunes”; (c) TB #s 16913, 16321–16330.

Diagnosis. Trichiotes lightfooti can be separated from Trichiotes seriatus Casey based on the following character combination: vertex of head and pronotal disc rivose; pronotum strongly posteriorly constricted (anterior margin ~1.4× posterior margin length) and densely foveate on disc; and bearing a single row of stridulatory pegs on abdominal ventrites 1 and 2.

Description. Length 4.4–5.9 (mean 5.1) mm, width 2.4–3.2 (mean 2.9) mm (n= 61 specimens). Cuticle ferruginous to brunneus, setae yellow-white to nearly clear in color; elytral width approximately 1.4× pronotal width. Head: Punctures each bearing one seta, predominantly long, erect setae with short, decumbent setae interspersed. Eye coarsely faceted, weakly ovoid to nearly round. Supra-ocular carina present, extending from near posterior of eye to epistoma, not reaching epistomal margin; moderately deep elongate depression present on frons along inner margin of carina above eye. Vertex rivose posteriad, densely punctate. Frons moderately punctate, fronto-clypeal suture not indicated; clypeal region weakly rugulose anteriorly, with moderately dense fine punctures; anterior clypeal margin broadly acuminate, extended past epistomal margin. Epistoma weakly rounded and not extending further than eye laterally, anterior margin curved to clypeus, anterior angles prominent. Gena impressed, largely impunctate, with deep groove directly anteroventral of eye. Head capsule sharply constricted laterally and ventrally posterior to eye, with deep ventral pits at constriction posterior to mandible base in lateral view, ventral extent scabriculous. Submentum transverse, as long as base of mentum. Labrum light yellow, anterior margin complete, weakly convex. Mandibles laterally densely finely punctate basally, each puncture with one medium to long seta, mesially impressed, bifid, dorsal surface with a single tooth, lower portion of mandible strongly projecting. Mentum trapezoidal, apical margin convex, feebly emarginate medially. Ligula membranous and concealed. Distal maxillary palp securiform-elongate. Antenna filiform, weakly clavate, with 11 antennomeres; antennomeres 9–11 with tomentose sensilla anteriorly and forming a loose club, antennomere 11 weakly acuminate. Prothorax: Pronotum rivose/rugose, densely foveate, each fovea bearing one seta, predominantly long, erect setae with short, decumbent setae interspersed. Shape convex, strongly constricted posteriorly, width approximately 1.5× length, anterior margin approximately 1.4× posterior margin length; lateral margins expanded at midpoint, not parallel sided; lateral carina absent; anterior apices acute, slightly divergent, and projecting; posterior apices acute, slightly projecting, posterior margin glabrous. Hypomeron densely foveate, each fovea with one short, decumbent seta, with feebly raised, ovoid impunctate region directly dorso-posteriad procoxal cavity. Prosternum and prosternal process densely foveate, each fovea with erect or decumbent seta; prosternal process weakly medially expanded, anteriorly raised, apex feebly convex, extended past posterior edge. Pterothorax: Nearly ovoid, feebly parallel-sided, apterous, elytral cavity sealed. Scutellum glabrous, broadly triangular, anterior edge feebly raised. Elytron moderately inflexed at sides, with humerus obsolete; dense longitudinal series of dense fovea present, each fovea with a short, decumbent seta; moderate longitudinal series of fine punctures present interstitially, each with a long, erect seta; transverse dorsal carina present along basal elytral margin to humerus, lateral carina absent. Epiplural carina present from elytral humerus to caudal tip; moderately fine punctures present on epipleuron, each with short, decumbent seta. All visible pterothoracic ventrites densely foveate, each fovea with a medium, erect seta. Mesoventrite weakly anteriorly impressed, posteriorly projecting medial process, apex truncate/emarginate; mesocoxal cavities closed. Legs: Coxal punctures each with short, decumbent seta; procoxae globular, weakly rugulose, densely punctate; and mesocoxae globular densely punctate; metacoxae transverse, dorso-anterior surface impunctate, mesial and posterior surfaces moderately punctate. Femora dorso-ventrally flattened, moderately setose, metafemora bearing a short distal scraper on the proximal surface. Tibia moderately punctate, each puncture with one long, erect seta, gold-yellow spines sparsely present on lateral margins, apices slightly expanded, gold-yellow spines sparsely present apically, apical spurs no longer than basitarsus, protibia dorsally serrate with each serration bearing a gold-yellow spine, metatibia bearing a fine file on the basal proximal surface ( Fig. 3E ). Tarsi moderately punctate on dorsal and lateral surfaces, each puncture with one short yellow-white decumbent seta, plantar surface densely punctate, each fine puncture with a short, decumbent golden seta, short golden spines present apically; tarsal formula 5-5-4. Abdomen: Punctures each bearing one seta, predominantly long, decumbent setae with short, decumbent setae interspersed. Intercoxal process acute at apex; abdominal ventrites 1–2 moderately punctate medially to sparsely punctate laterally, ventrite 3 moderately punctate, ventrites 4–5 densely punctate; abdominal ventrites 1 and 2 each with one curved row of stridulatory pegs laterally, extending mesially, past the anterior apices ( Fig. 3 , C and D); ventrites 3–5 expanded laterally, obscuring epipleural margin in ventral view.

Variation. Males appear to be nearly identical to the females, with genital dissection being required to confirm sex.

Distribution. Cuatrociénegas Protected Area, Coahuila, Mexico.

Etymology. The species epithet is in honor of David C. Lightfoot, desert biologist, specialist in North American Orthoptera, and one of the organizers of the UNMC 2011 expedition; with our thanks for bringing the holotype specimen to our attention.

Figures

FIGURE 1. Distribution of Trichiotes species. Trichiotes seriatus Casey, 1907 (black triangle), T. lightfooti sp. nov. (white circle with star).

FIGURE 2. Trichiotes lightfooti sp. nov., holotype (female) A) Dorsal habitus. B) Lateral habitus.

FIGURE 3. A) Trichiotes lightfooti pronotum (foveae and setae omitted). B) Trichiotes seriatus pronotum (foveae and setae omitted). C) Trichiotes lightfooti abdominal ventrites 1 and 2. D) Trichiotes seriatus abdominal ventrites 1 and 2. E) Proximal extent of T. lightfooti metafemora and metatibia.

FIGURE 5. Pruinescence in Trichiotes Casey. A) Trichiotes seriatus (TB # 16355). B) Trichiotes lightfooti sp. nov. (TB # 16923), scale = 10 µm. P = waxy, filamentous pruinescence; S = seta.