Pharaxonotha woodruffi 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 : 26-27

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

Figures 9A–K

Diagnosis. Distinguished from other Pharaxonotha by the more flattened head, posterior lateral margin of eye without distinct fringe of setae; pronotal length/elytral length (PL/EL) = 0.32–0.37; sexual dimorphism with males having robust femora, protibial and protarsomeres, and male parameres in dorsal view with margins nearly straight. Also found inhabiting Dioon spinulosum in northeastern Oaxaca.

Description. Length 3.05–3.36 mm, width 1.20–1.32 mm. General body color ( Fig. 9A–C ) pale brown, pronotum slightly darker; dorsal surface with short setae not reaching neighboring punctures.

Head. Not broad, width = 0.69–0.71× pronotal width ( Fig. 9D–F ); in lateral view notably narrow, flattened; in dorsal view conical, gradually narrowed anteriorly, surface flat to slightly convex, moderately punctured, average distance between closest punctures 2–3× width of puncture; head width 0.65–0.73 mm; dorsal interocular distance 0.40–0.48 mm, head width/dorsal interocular distance ratio 1.52–1.63, ventral interocular distance 0.33–0.38 mm, head width/ventral interocular distance ratio 1.92–2.00. Eye with large black facets, about 2× diameter of head punctures; lacking separate fringe of setae posterior of eye. Antennal length slightly longer than pronotal width, 1.6× head width; antennomere I (scape) fairly large, slightly elongate; antennomere II shorter than III; IV 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 not enlarged, 1.1× longer than X, globular with rounded apex. Clypeus weakly concave anteriorly, moderately punctate. Transverse occipital line [vertexal line] absent medially. Mentum and submentum fine punctured, 1/3× diameter of facet, distance between nearest punctures approximately 2–3× 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 0.72–0.78; with distinct marginal carina laterally and basally, anteriorly with fine marginal carina medially; dorsally flattened; anterior angles narrowly rounded, projecting forward; posterior angles weakly 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 fine 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 minute punctures. Scutellar shield distinctly transverse, posterior margin weakly roundly pentagonal.

Elytra in dorsal view elongate, flattened dorsally; length/width 1.62–1.77, greatest width near midlength; with distinct marginal line basally; 10 complete striae of moderate puncture size; scutellary striole extending ¼ elytral length, with 11–15 punctures; punctures of elytral striae 1.5× larger than pronotal punctures, striae weakly impressed; intervals of striae with fine, shallow punctures, ¼ size of strial punctures; all punctures of elytra bearing a single 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 moderate lateral punctation separated by 2–3× own diameter; medial surface finely distinctly punctured, separated by 4–5× own diameter; surface medially flattened, metathoracic discrimen extending approximately ¾ metaventrite length. Legs broadened, relatively similar in length and shape. Procoxa oval; mesocoxa globular; metacoxa transversely elongate-oval; trochanters obliquely truncate apically; femora robust, compressed laterally; tibiae shorter than femora, narrowly triangularly 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, fine 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 genitalia (n = 1): not distinctly dorsoventrally flattened, tegmen in dorsal view with basal piece ring-like; parameres in dorsal view symmetrical, gradually expanding to rounded apex, inner and outer margins approximately straight, without lateral bulge, in lateral view length = 4.5× greatest width; elongate cylindrical median lobe narrowing apically; long coiled flagellum ( Fig. 9G–I ).

Female. Similar to male; sexual dimorphism weakly evident; femora, protibia and basal protarsomeres of male more broadly dilated. Genitalia (n = 1); gonostylus cylindrical, widest at apex, tapering slightly and gradually to base, set apically on gonocoxite, gonostylus length = 3.5× greatest width ( Fig. 9J ). Spermatheca arcuate, but not C-shaped, short and compact, length = 2.6× greatest width, slightly asymmetric, widest in apical half, base and apex rounded ( Fig. 9K ).

Distribution. Known from D. spinulosum , which inhabit limestone mogotes in lowland wet forest of northeastern Oaxaca.

Material examined. Holotype (by designation) male of Pharaxonotha woodruffi with the following labels: 1) [rectangular; white; printed in black ink] “ MEXICO, Oax. Hwy147, 6 mi. SE. Jcn. 175&147, 200’, 25Aug. 1982, C. & L. O’Brien & G. Wibmer; 2) [rectangular; white; printed in black ink] ex: male strobile Dioon spinulosum ; 3) [rectangular; red; printed in black ink] “ HOLOTYPE ♂ Pharaxonotha woodruffi Skelley, Tang and Pérez-Farrera 2022 ”. Deposited in the FSCA.

Paratypes (total 4). Allotype and 3 paratypes with same data as holotype deposited at the FSCA .

Etymology. The species is dedicated to Robert E. “Bob” Woodruff, mentor and advisor of author PES. Unlike most graduate advisors, he allowed PES freedom to work on whatever beetles were of interest. This freedom allowed PES to explore the Erotylidae , which eventually lead to all of the recent work on Pharaxonotha .

Remarks. Pharaxonotha woodruffi has been found together on male Dioon spinulosum cones with a species of Allocorynina weevil, Rhopalotria (Allocorynus) vovidesi O’Brien and Tang ( O’Brien and Tang 2015) . These or related beetles may also be present on the closely related Dioon rzedowskii , also found in wet forests of northeastern Oaxaca, but at higher altitudes on steep limestone slopes.

Kirschii species group

Adult diagnosis. The kirschii species group can be distinguished from other Pharaxonotha by a more robust head that has a temple behind the eye, and male with a small tooth or denticle at apex of terminal abdominal ventrite. Like species inhabiting other cycad genera, Ceratozamia , Microcycas and Zamia , this group has relatively short indistinct dorsal body hairs emerging from punctures at 30× magnification. Other species groups found on Dioon are generally characterized by having setae longer than species found on these other cycad genera. Excluding the elytra, the dark brown body is the darkest of all known Pharaxonotha . Only the elytra of the bicolor species group are darker.

Remarks. This species group is proposed based on analysis of the 16S rRNA gene of two populations that are part of the early diverging lineages in Tang et al. (2018b, 2020). Materials of the kirschii group analyzed by Tang et al. (2018b: 8, fig.4; 2020: 18, fig. 3) are presented in their trees labeled as follows: “D0057 Veracruz – Z. inermis ” and “D0068 C. Amer. – not on cycads – Pharaxonotha kirschii ”. These two are widely separated from the majority of other lineages but also shows a cycad-inhabiting species to be more divergent from a free-living P. kirschii than many species are from each other. Members of this group are known from other genera of cycads and likely represents a complex of species. Further work is needed on both the cycad associated and the free-living populations. Dissected adult specimens from both new species collected with cycads usually have their guts packed with the distinctive monosulcate pollen grains of cycads, indicating that this is a major food source.

Figures

Figure 9. Pharaxonotha woodruffi from Oaxaca, Mexico (A–I: male holotype; J–K: female allotype). A–C) Dorsal, lateral and ventral habitus. D–F) head, dorsal, oblique lateral and ventral views. G) Genital capsule attached to tegmen and median lobe, ventral view.H) Tegmen attached to median lobe, lateral view. I) Parameres of tegmen, ventral view top and lateral view bottom. J) Retracted ovipositor, ventral view. K) Spermatheca (fully inflated).