Yumtaax veracrucensis Beza-Beza, Reyes-Castillo & Jameson

Beza-Beza, Cristian Fernando, Beck, James, Reyes-Castillo, Pedro & Jameson, Mary Liz, 2017, Phylogeny of the genus Yumtaax Boucher (Coleoptera, Passalidae, Proculini): Taxonomic and evolutionary implications with descriptions of three new species, ZooKeys 667, pp. 95-129 : 110-113

Yumtaax veracrucensis Beza-Beza, Reyes-Castillo & Jameson sp. n.

Material examined.

Seven type specimens (two males, four females, and two sex unknown).

Holotype ♂. MEXICO: Veracruz, Municipio de Coatepec, Reserva de La Cortadura, 1895-1900 msnm, bosque mesófilo de montaña, colecta en un tronco podrido, interior del bosque, V-2-2005 (P. Reyes-Castillo) (IEXA).

Paratypes. MEXICO: 1 ♂, 3 ♀. Veracruz, Municipio de Coatepec, Reserva de La Cortadura, 1895-1900 msnm, bosque mesófilo de montaña, colecta en un tronco podrido, interior del bosque, V-2-2005 (P. Reyes-Castillo) (IEXA, CFBB). Chiconquiaco: 1 ♂. Veracruz. Congr. La Guacamaya, X-6-2008 (P. Rojas); 2 sex unknown Near La Parra, IX-17-1995 (J. Bueno); One paratype is molecular voucher CB0035 (CFBB).

Diagnosis.

Yumtaax veracrucensis is a small (17.5-20.0 mm), macropterous species that is a member of the Y. imbellis clade (Fig. 4). This species is diagnosed by the following character combination: the clypeus is vertical (shared with Y. laticornis , Y. cameliae ; inclined in other members of Yumtaax ) and with the anterior border straight (shared with other members of Yumtaax except for Y. recticornis and Y. olmecae that have a concave anterior border); mesofrontal structure (MFS) of the “falsus” type (see Reyes-Castillo 1970) (shared with all members of Yumtaax except Y. cameliae which has the MFS of the “striatopunctatus” type) with the central tooth largely free (shared with Y. recticornis , Y. laticornis , Y. cameliae , Y. mazatecus ; fused with frontal ridges in Y. jimenezi , Y. imbellis , Y. nebulosus , Y. olmecae ), directed anteriorly (shared with Y. laticornis ; directed dorsally in Y. recticornis , Y. imbellis , Y. nebulosus , Y. olmecae ; directed dorsally and anteriorly in Y. jimenezi , Y. mazatecus ; elevated in the posterior half bending abruptly forward in the anterior half in Y. cameliae ), and reaching the frontoclypeal suture (shared with Y. laticornis , Y. cameliae ; not reaching the clypeus in other members of Yumtaax ); and reduced eyes (shared with Y. cameliae , Y. jimenezi , Y. nebulosus , Y. olmecae ; large in Y. recticornis , Y. imbellis ; strongly reduced in Y. laticornis , Y. mazatecus ).

Dimensions

(mm) (n = 4). Total length 17.5-20.0 ( χ = 19.0); elytral length 10.5-11.5 ( χ = 11.0); pronotal length 4.0-5.0 ( χ = 4.5); pronotal width 5.0-6.5 ( χ = 6.0); humeral width 5.0-6.5 ( χ = 6.0).

Description of holotype

(Fig. 6). Head (Fig. 6C). Labrum: anterior border concave, dorsal surface smooth and glabrous medially, punctate and setose apicolaterally, apically, and basally; anterior edge excavated. Clypeus: vertical, rectangular, flat, shiny, and smooth. Frontoclypeal suture: straight, and opaque; external tubercles rounded, directed anteriorly and laterally. Frontal area: horizontal, flat, smooth and shiny, frontal ridges weak finishing in inner tubercles; inner tubercles smaller than external tubercles. Frontal fossae: punctate and setose. Mesofrontal structure (MFS): of the “falsus” type (see Reyes-Castillo 1970); base subparallel, slightly narrower than MFS’ lateral ridges; center horn long with apex acute, largely free and directed anteriorly (Fig. 6D), surpass ing posterior margin of clypeus, dorsally with sparse micro-punctures; base of the center horn wide, narrowing gradually until apex; dorsal fossa present at the base of MFS. Occipital fossa: shallow posteriorly and deeper laterally connected with the frontal fossae. Posterior occipital sulcus sinuate. Supraorbital ridge: bituberculate, tubercles of similar size; posterior half of supraorbital ridge not bifurcated. Canthus: with apex rounded, almost oblique, covering 1/3 of the eye, not expanded distally. Eyes: reduced (distal edge of the eye not reaching the distal edge of the canthus), width = 0.3 mm (each eye). Head width = 3.0 mm. Ratio of sums of both eyes widths/total head width = 0.2; postocular area punctate and setose. Ligula: tridentate, central tooth surpassing apex of lateral teeth; lateral teeth rounded; setose punctures present in discal area; posterior border convex. Mentum: lateral lobes rounded and wide, with setose punctures. Basomedial portion protruding ventrally; anterior border at the middle convex; basal fossae present with setose punctures. Hypostomal process: without lateral depression; separated from the mentum by a distance shorter than the width of the anterior width of the hypostomal process. Infraocular ridge (e.g., Fig. 3): short, weak, and wide anteriorly. Mandible: with 3 apical teeth; internal tooth in left mandible tridentate; dorsal tooth occupies at least half length of the mandible. Pronotum: anterior angles rounded. Anterior fossae of marginal sulcus punctate. Lateral fossae without punctures. Marginal groove lacking punctures. Prosternum: opaque; prosternellum with anterior and lateral edges rugose and opaque, anteriorly and posteriorly shiny. Scutellum: smooth and glabrous. Mesosternum: with anterior-lateral areas opaque. Metasternum: with setae anterolaterally, lacking punctures in lateral margins of metasternal disc. Lateral fossae wide posteriorly with setose punctuations. Elytra: anterior border straight. Meeting point of striae 1-10 (see Reyes-Castillo 1970) with one line of punctures. Wings: well developed. Legs: femur I with longitudinal anteroventral groove weakly developed, not reaching the distal part of the femur, posteroventral half pubescent; setae long, sparse, reddish. Abdomen: last sternite with marginal groove incomplete (Fig. 6B). Aedeagus (Fig. 6E, F): in dorsal view phallus elongated (longer than wider). In ventral view distal edges of the phallus more or less at the same level of distal edges of parameres.

Variation.

Paratypes vary from the holotype by the following characteristics: internal tubercles weak to obsolete; frontal fossae glabrous or setose; ratio of eyes to head width vary between 0.19 and 0.22; basal fossae of mentum strong, opaque and glabrous or shiny and with setose punctures; infraocular ridge weak or absent; femur I with longitudinal antero-ventral groove weakly developed to obsolete.

Etymology.

This species is named after its home state of Veracruz in Mexico.

Distribution.

This species is known from cloud forest between around 1900 m in the transverse neo-volcanic system, Mexico. The surrounding states and areas in which this species is distributed have been well-collected, and Y. veracrucensis has only been found at three localities in Veracruz, Mexico: La Cortadura Natural Reserve near Coatepec; Chiconquiaco (near La Parra); and the road between Las Minas and Xalapa; Chiconquiaco; Congr. La Guacamaya (19°45'51.4"N, 96°48'1.7"W).

Remarks.

Specimens of Y. veracrucensis were originally identified as P. orizabae and were collected in Reserva La Cortadura in Coatepec, Veracruz, Mexico. Based on our phylogenetic analysis, Y. veracrucensis ( Y. LCM) and Y. imbellis are potential sister species (Fig. 4; PP 0.99/BS 90). Molecular distinctiveness and form of the dorsal ridge in tibia II (as in all species of Yumtaax ) provide support that this is a distinct species within the genus Yumtaax .