Pharaxonotha Reitter, 1875

Tang, William, Skelley, Paul E., Taylor B, Alberto S. & Salzman, Shayla, 2024, Review of Pharaxonotha Reitter (Coleoptera: Erotylidae: Pharaxonothinae) inhabiting cones of the cycad Zamia L. (Cycadales) in Panama, with descriptions of five new species, Insecta Mundi 2024 (43), pp. 1-40 : 4-5

Pharaxonotha Reitter

Type species. Pharaxonotha kirschii Reitter , by monotypy.

Diagnosis. Pharaxonotha can be distinguished from other members of the Pharaxonothinae by the following combination of characters: antennal club of 3 antennomeres; eyes large, encroaching upon gular area; submentalgular suture apparently lacking; transverse occipital line distinct; stridulatory files at base of head separated by distance ≈ width of scutellar shield; anterior pronotal margin lacking marginal line; lateral pronotal carina narrow, same thickness along entire length; elytra with basal bead; internal abdominal calli absent; male genitalia with median lobe cylindrical and tegmen laterally flattened, but not twisted; known distribution includes the Caribbean Basin from the U.S.A. (Florida, Louisiana and Texas), Bahamas, Greater Antillean islands of Cayman Islands, Cuba, Jamaica, Hispaniola and Puerto Rico; Mexico, Central America into South America as far south as Bolivia.

Description. Length 1.59–5.09 mm, width 0.60–1.89 mm. Body in dorsal view elongate, somewhat cylindrical, greatest width at middle of elytra; in lateral view weakly convex dorsally. Body color usually entirely pale yellow-brown to medium brown, but in a few species elytra black to dark brown or elytra and ventral tergites with black to dark brown maculation; dorsal and ventral surfaces punctate, weakly alutaceous to smooth, shining, procumbent setae usually associated with punctation, setal length ranging from short, not reaching distance to nearest puncture, to long and extending beyond nearest puncture.

Head. Not broad, width = 0.65–0.80× pronotal width; in dorsal view conical, gradually narrowed anteriorly, surface flat to slightly convex, finely, moderately punctured, average distance between closest punctures 3–4× width of puncture; head width 0.40–1.07 mm; dorsal interocular distance 0.26–0.68 mm, head width/dorsal interocular distance ratio 1.55–1.91, ventral interocular distance 0.14–0.58 mm, head width/ventral interocular distance ratio 2.63–2.86. Eye with large black facets, about 2× diameter of head punctures. Antennal length slightly shorter than pronotal width, 1.2× head width; antennomere I (scape) fairly large, slightly elongate; antennomere II slightly larger than III; IV circular; IV–VIII small, equal in length, VII–VIII becoming slightly wider with flattened apex; club fairly large, IX and X similar in length; XI not enlarged, slightly longer than X, globular with rounded apex. Clypeus weakly concave anteriorly, moderately punctate. Transverse occipital line [vertexal line] distinct from eye to eye. Mentum and submentum coarsely punctured, distance between nearest punctures approximately 2–3× own diameter, each puncture with a short seta; submentum with weak medial depression visible on some. Gular area smooth, without punctation or setae, border with submentum marked by change in punctation and with a shallow transverse depression.

Thorax. With pronotum transversely quadrate in dorsal view, length/width ratio 0.73–0.77; with distinct marginal carina laterally and basally, anteriorly with fine marginal carina medially; surface mostly convex, slightly flattened medially; anterior angles broadly rounded, not projecting forward; posterior angles rounded, usually with small denticle at angle; lateral margin evenly shallowly arcuate medially, more strongly arched anteriorly and posteriorly; posterior margin slightly projecting medially, projection beginning approximately by pair of small, dark pores in margin located 1/4 width from posterior angles, each pore marks base place where an indistinct sulcus may extend anteriorly onto disc at most 1/8 length of pronotum, sulcus usually lacking. 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 convex apically, expanded and truncate at apex. Hypomeron laterally with few minute punctures, medially lacking distinct longitudinal striations. Scutellar shield distinctly transverse pentagonal, posterior margin weakly rounded. Elytra in dorsal view elongate, convex; length/width 1.66–1.78, greatest width near midlength; with distinct marginal line basally; 10 complete striae of moderate puncture size; scutellary striole extending 1/4 elytral length, with 10–15 punctures; punctures of elytral striae slightly larger than pronotal punctures, striae not impressed; intervals of striae with fine, shallow punctures, 1/2 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 fine indistinct punctation. Metaventrite glossy, with weak lateral punctation separated by 4–5× own diameter; medial surface indistinctly punctured; entire surface convex, metathoracic discrimen extending approximately 3/4 metaventrite length. Legs narrow, relatively similar in length and shape. Procoxa oval; mesocoxa globular; metacoxa transversely elongate-oval; trochanters obliquely truncate apically; femora weakly robust, moderately compressed laterally; tibiae shorter than femora, weakly widening to truncate apices; protibia with apical lateral tooth weak, with complete apical fringe of short spinules on straight ventral apical margin; meso- and metatibia with apical fringe of short spinules on anterior margin, finer setae on posterior margins.

Abdomen. Ventrite apical margin bearing short, sparse setae; internal abdominal calli absent; all ventrites finely, sparsely punctate across surface, distance to nearest puncture approximately 4–5× 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 = 104) dorsoventrally flattened, in repose oriented upside down inside abdomen with tegmen positioned ventrad of the median lobe [while it is common in the Cucujoidea for the male genitalia to be rotated 90 degrees while retracted into the abdomen ( McHugh et al. 1997), 180 degrees is unusual]; tegmen not flattened, basal piece broadened and ring-like to hold coiled flagellum, parameres in dorso-ventral view with sides parallel or bulging on outer side, apices symmetrical or asymmetrical; median lobe elongate, cylindrical; flagellum long, hair-like and coiled. Female genitalia (n = 131) gonostylus cylindrical with width equal throughout its length or widest at apex, tapering slightly and gradually to base, in both cases set apically on oblique apex of gonocoxite, or gonostylus ovate and short, length <3× width and inserted laterally below a truncated gonocoxite apex. Spermatheca (see Fig. 1 for definition of structures and orientations) either slightly arcuate, hook-shaped or C-shaped, with spermathecal duct and glandular ducts inserted on dorsal side of basal third, in pits or on swellings; apical third and basal third symmetrical or with asymmetric swellings dorsally; apical third or basal third either longer, shorter than each other, or of equal length, with annulations, longitudinal or oblique wrinkles or smooth; these structures highly diagnostic for distinguishing species and species groups.

Figures

Figure 1. Spermatheca of Pharaxonotha fawcettae Skelley, Tang and Pérez-Farrera from Jalpan de Serra, Querétaro, Mexico indicating the diagnostic structures and regions used in the key.