Pharaxonotha sclerotiza Skelley, Tang and Pérez-Farrera, 2022

Skelley, Paul E., Tang, William & Pérez-Farrera, Miguel Angel, 2022, Review of Pharaxonotha Reitter (Coleoptera: Erotylidae: Pharaxonothinae) inhabiting the cycad genus Dioon Lindl. (Cycadales), with descriptions of nine new species and comments on P. kirschii Reitter, Insecta Mundi 2022 (917), pp. 1-41 : 30-33

Pharaxonotha sclerotiza Skelley, Tang and Pérez-Farrera , new species

Figures 2F , 11A–K

Diagnosis. A member of the kirschii group this species has a striking sexual color dimorphism with the dorsal color of the male a uniform medium brown, while the pronotum and elytra of the female with only the medial half darkened into a fuscous spot. Other diagnostic characters include small antennomere XI, the female spermathecal apex gradually curving to a rounded point, and male paramere width in lateral view> 3.4× own length. It has been found at Gómez Farías, Tamaulipas, Mexico on Dioon angustifolium .

Description. Length 4.14–4.39 mm, width 1.58–1.60 mm. General body color ( Fig. 11A–D ) dark brown. General body ( Fig. 10A–F ) with the dorsal color of the male a uniform medium brown, while the pronotum and medial half of female elytra are dark brown to black. Dorsal surface glossy, with very short setae in puncture.

Head. Not broad, width = 0.67–0.68× pronotal width ( Fig. 11E–F ); in lateral view robust, clypeus to base of head dorsally convex; in dorsal view conical, gradually narrowed anteriorly, surface convex, coarsely punctured, average distance between closest punctures 2–3× width of puncture; head width 0.88–0.90 mm; dorsal interocular distance 0.59 mm, head width/dorsal interocular distance ratio 1.49–1.53, ventral interocular distance 0.50–0.54 mm, head width/ventral interocular distance ratio 1.63–1.80. Eye with large black facets, similar diameter of head punctures; head posterior of eye with a small tooth (temple) in dorsal profile. Antennal length slightly shorter than pronotal width, 1.5× head width; antennomere I (scape) fairly large, slightly elongate; antennomere II slightly shorter than III; IV small, circular; V–VII same length as IV, gradually becoming wider with VIII transverse and flattened apically; club fairly large, IX and X similar in length; XI small, 1.1× longer than X, globular with rounded apex. Clypeus weakly concave anteriorly, moderately punctate. Transverse occipital line [vertexal line] distinct nearly from eye to eye. Mentum and submentum coarsely punctured, ½–¾× diameter of facet, distance between nearest punctures approximately 1× own diameter, each puncture with a short seta. Gular area smooth, without punctation or setae, border with submentum marked by change in punctation.

Thorax. With pronotum transversely rectangular in dorsal view, length/width ratio 0.73–0.74; with distinct marginal carina laterally and basally, anteriorly with fine marginal carina medially; dorsally flattened; anterior angles sharply rounded, projecting forward; posterior angles developed, with small denticle at angle; lateral margin weakly arched in medial half, shallowly arcuate inward anteriorly and posteriorly; posterior margin slightly projecting medially, projection beginning approximately by pair of small, dark pores in margin located ¼ width from posterior angles, each pore marks base of a distinct sulcus extending anteriorly onto disc ¼ length of pronotum. Prosternum in ventral view convex, with few scattered punctures; anterior margin slightly emarginate, finely denticulate with row of long, anteriorly directed setae, longest setae approximately 1/3 length of eye; prosternal process flattened apically, expanded and truncate at apex. Hypomeron smooth, with few punctures. Scutellar shield distinctly transverse, posterior margin weakly roundly pentagonal. Elytra in dorsal view elongate, flattened dorsally; length/width 1.83–1.84, greatest width near midlength; with distinct marginal line basally; 10 complete striae of moderate puncture size; scutellary striole extending 1⁄5 elytral length, with 9–10 punctures; punctures of elytral striae 2× larger than pronotal punctures, striae weakly impressed; intervals of striae with fine, indistinct shallow punctures, 1⁄5 size of strial punctures; all punctures of elytral bearing a single very short seta; seta only visible in profile, extending slightly out of puncture. Mesoventrite with strong punctation, distance between nearest punctures approximately equal to diameter of punctures, puncture depth moderate. Metaventrite glossy, with strong lateral punctation separated by 1–2× own diameter; medial surface finely distinctly punctured, separated by 3–4× own diameter; surface medially flattened, metathoracic discrimen extending approximately ½ metaventrite length. Legs narrow, relatively similar in length and shape. Procoxa oval; mesocoxa globular; metacoxa transversely elongate-oval; trochanters obliquely truncate apically; femora narrowly oblong, compressed laterally; tibiae shorter than femora, weakly dilated to obliquely truncate apices; protibia with apical lateral tooth small, with complete apical fringe of very short stout spinules on straight ventral apical margin; meso- and metatibia with apical fringe of short stout spinules on anterior margin, finer setae on posterior margins.

Abdomen. Ventrite apical margin bearing short, sparse setae; all ventrites bearing moderate, shallow punctation evenly distributed across surface, distance to nearest puncture approximately 2× diameter of puncture, punctures bearing mostly reclining setae; ventrite V with setae length nearly uniformly approximately 2× diameter of puncture; I–IV each with 2 or more median pairs of longer, semi-erect sensory hairs (difficult to see in poor lighting, often abraded); male ventrite 5 with small denticle at apex. Male genitalia (n = 1): not distinctly dorsoventrally flattened, tegmen in dorsal view with basal piece ring-like and wide; parameres in dorsal view with lateral margins approximately straight to midlength, apical half with inner margin straight and outer margin curving slightly and bulging, in lateral view length = 3.5× greatest width; elongate cylindrical median lobe with lateral margins tapering strongly apically; long coiled flagellum ( Fig. 11G–I ).

Female. Similar to male. Female differs in having dark central markings on eltyra; female protibial and protarsus narrow, male with weakly dilated protibial and basal protarsomeres. Female lacking apical denticle on terminal abdominal ventrite. Genitalia (n = 1); gonostylus cylindrical, widest at apex, tapering slightly and gradually to base, set apically on gonocoxite, gonostylus length = 4.2–4.6× greatest width ( Fig. 11J ). Spermatheca hook-shaped, base rounded on dorsal side, angulate on ventral side, width greatest just apicad of base, then narrowing evenly until reaching unsclerotized arc at central third, apical third narrowing and curving evenly from junction with central third until rounded apex, length = 5.4× greatest width ( Fig. 11K ).

Distribution. This species is known from the Mexican states of Nuevo León, Querétaro and Tamaulipas. At the type locality at Gómez Farías, Tamaulipas the host plant Dioon angustifolium , grows in fissures on limestone and except for scattered low trees are exposed to full sun.

Material examined. Holotype (by designation) male of Pharaxonotha sclerotiza with the following labels: 1) [rectangular; white; printed in black ink] “ MEXICO, Tamp., Gómez Farías , tsinge limestone, [GPS omitted], cone ♂ Dioon angustifolium , 12-XI-2014, W. Tang ”; 2) [rectangular; red; printed in black ink] “ HOLOTYPE ♂ Pharaxonotha sclerotiza Skelley, Tang and Pérez-Farrera 2022 ”. Deposited in the FSCA.

Paratypes (total 1). Allotype with same data as holotype, deposited in FSCA.

Additional specimens (total 6). Material studied presently considered to be P. sclerotiza , but not designated as paratypes: MEXICO: Nuevo León: 16 mi. W. Linares, Hwy 58, 11-IX-1982, C. W. & L. O’Brien & G. Wibmer, emerged ex male strobili Dioon edule summer 1984 (3 FSCA). Querétaro: Arroyo Seco, San José de la

Flores, [GPS coord. omitted], 6-VII-2003, J. A. Peréz de la Rosa y G. Vargas Coll. Ex Dioon edule (cono femenino) (3 CZUG, FSCA)

Etymology. While not as heavily sclerotized as P. kirschii , this species is more sclerotized than other cycad dwelling species. It is named for this more heavily sclerotized body.

Remarks. The specimens from Querétaro show some variation in coloration, different from those described from Tamaulipas. The single female has entirely fuscous elytra, lacking dark maculations, while one male is entirely dark brown and the other entirely fuscous. No morphological character was found to separate these from the type series. Based on the paucity of specimens we prefer to consider this population as P. sclerotiza until series of specimens and potential molecular analyses are available.

At the type locality only two specimens of Pharaxonotha sclerotiza were found together with 28 individuals of P. vovidesi on a male cone of D. angustifolium that was at the end stage of pollen shedding. The difference in numbers bring up the possibility that these two species of Pharaxonotha , while sharing the same spatial niche, may have differing temporal niches, with preferences to feed and/or reproduce in the cone at different stages of cone development. The non-paratype specimens from Querétaro, however, were collected on a female cone. While adults of the kirschii group have been found feeding on pollen, it is possible they may breed in decaying female cones also. Thus, species of Pharaxonotha may stratify the niches based on cone gender. To our knowledge, no efforts have been made to sample beetles from mature female cones. There is no indication if the female cone the non-paratypes were found on was young or mature. In D. angustifolium at the type locality P. sclerotiza also occurred with the Allocorynina weevil Parallocorynus (P.) norstogi ( O’Brien and Tang 2015).

Figures

Figure 2. Pharaxonotha body parts. A–C) Dorsal view of head. A) P. kirschii, Mpio. Jalpan, Querétaro, Mexico. Arrow points to temple. B) P. occidentalis, paratype, El Campanario, Chiapas, Mexico. C) P. vovidesi, paratype, Mt. Oscuro, Veracruz, Mexico.D) P. kirschii, abdominal ventrites, Mpio. Jalpan, Querétaro, Mexico. Arrow points to tooth on ventrite 5. E–F) Antennal clubs. E) P. kirschii, Santa Isabel, Chiapas, Mexico.F) P. sclerotiza, holotype. G) Spermatheca of Pharaxonotha fawcettae from Jalpan de Serra, Querétaro, Mexico indicating the diagnostic structures and orientations used in descriptions.

Figure 10. Pharaxonotha dimorpha from El Farallón, Veracruz, Mexico (B–G: male holotype). A) Female allotype, dorsal habitus. B–D) Male dorsal, lateral and ventral habitus. E–F) Male head, dorsal and ventral views. G) Tegmen attached to median lobe and genital capsule, lateral view. H) Male genital capsule, dorsal view.I) Tegmen attached to median lobe, lateral view top and ventral view bottom. J) Parameres of tegmen, ventral view top and lateral view bottom. K) Retracted ovipositor, ventral view. L) Spermatheca (fully inflated).

Figure 11. Pharaxonotha sclerotiza from Gómez Farias, San Luis Potosí, Mexico (B–I: male holotype). A) Female allotype, dorsal habitus. B–D) Male dorsal, lateral and ventral habitus. E–F) Male head, dorsal and ventral views. G) Tegmen attached to median lobe and genital capsule, ventral views. H) Tegmen attached to median lobe, lateral view. I) Parameres of tegmen, ventral view top and lateral view bottom. J) Spermatheca and retracted ovipositor, ventral view. K) Spermatheca (fully inflated).