Ceratophila, Tang, Skelley & Perez-Farrera, 2018

Tang, William & Dominguez, Hector Gomez, 2022, Two new species of Pharaxonothinae beetles (Coleoptera: Erotylidae) inhabiting cones of the cycad Ceratozamia santillanii Pérez-Farr. & Vovides (Cycadales: Zamiaceae) in Mexico, Zootaxa 5150 (3), pp. 428-442 : 430-432

Key to described species of Ceratophila and Pharaxonotha on Ceratozamia

(modified from Tang et al. 2018a)

The key and species descriptions that follow rely on the morphology of spermatheca in female genitalia, particularly in Pharaxonotha (see Fig. 2 for terminology and orientations used). For other diagnostic characters used in the key see Fig. 3 .

Morphological and molecular data suggest that there are more undescribed species of Pharaxonotha and Ceratophila than are presented in the key below ( Tang et al. 2018 a, 2020; Tang unpublished data). A key to Pharaxonotha inhabiting Dioon was recently published by Skelley et al. (2022) and keys for Pharaxonotha inhabiting Ceratozamia and/or Zamia inhabiting other regions are currently in progress and will be published elsewhere.

Because of variable and overlapping morphological character states with some species, it is desirable, and in some cases necessary, to have a series of specimens representing color variations and both sexes to properly identify a species. In the following key, text in brackets before the species name indicate the states of Mexico where it occurs and the known host species of Ceratozamia .

Concerns remain with the identity of some species described in Tang et al. (2018a) and those of Santiago-Jiménez et al. (2019) (see Skelley and Tang 2020). Based on descriptions and photographs in Santiago-Jimenez et al. (2019), compared with photographs of the holotypes and additional specimens collected from the same host at the type locality, some may have been described twice. The tentative pairings are listed in the key with a question mark ‘?’. These will be more thoroughly addressed and identities resolved in a future paper covering Ceratophila and Pharaxonotha on Ceratozamia in Veracruz.

1. Lateral pronotal carinae thicker anteriorly in lateral view ( Fig. 3D, E ); elytra without a basal bead; head with supraocular lines, stridulatory files at base of head separated by distance ≈ ½ width of scutellar shield ( Fig. 3B ); tarsomeres I–III distinctly widened, metatarsomere I width> length................................................. [genus Ceratophila ] … 2

- Lateral pronotal carinae in lateral view narrow, same thickness for entire length ( Fig. 3C ); elytra with a basal bead ( Fig. 3A ); head without supraocular lines, stridulatory files at base of head separated by distance ≈ width of scutellar shield ( Fig. 3A ); tarsomeres I–III not distinctly widened, metatarsomere I width <length.................... [genus Pharaxonotha ] … 9

2 (1). Pronotum in dorsal view, with anterior half of lateral carinae converging anteriorly; not explanate laterally, surface convexly curved to lateral carinae; lateral carinae in lateral view distinctly thicker anteriorly, anterior thickness 2× posterior thickness ( Fig. 3D ); pronotal disc lacking longitudinal groove extending anteriorly from lateral basal pore in margin ( Fig. 3B ); metatibia triangularly dilated toward apex ( Fig. 3F )............................................ [subgenus Ceratophila ] … 3

- Pronotum, in dorsal view, with central 2/3 of lateral carinae nearly parallel ( Figs. 4A , 5A ), explanate laterally, surface broadly concave near lateral carinae; lateral carina weakly thickening anteriorly, anterior thickness <1.5× that at base ( Fig. 3E ); pronotal disc with longitudinal groove extending anteriorly from lateral basal pore in margin ( Fig. 3A ); metatibia not triangularly dilated toward apex ( Fig. 3G )............................. [subgenus Vovidesa Tang, Skelley & Pérez-Farrera ] … 6

3(2). Head with broad medial transverse ridge anterior of a distinct transverse basal groove in males ( Fig. 3B ), ridge and groove weak in females, ridge interrupting supraocular line in both male and female; head broad, width = 0.74–0.75× pronotal width; anterior clypeal margin emarginate; pronotal hypomeron densely punctate; [Veracruz — C. euryphyllidia Vázq.Torres, Sabato & D.W. Stev. ]................................................ C. (C.) chemnicki Tang, Skelley & Pérez-Farrera

- Base of head at most with indistinct shallow transverse groove, supraocular line complete; head narrower, width = 0.66–0.68× pronotal width; anterior clypeal margin truncate or weakly convex; pronotal hypomeron with punctures sparse and minute or lacking............................................................................................. 4

4(3). Dark elytral markings (when present) laterally covering most of disc; pronotum generally more elongate, pronotal length/pronotal width (PL/PW) = 0.83–0.90; [Chiapas — C. alvarezii Pérez-Farr., Vovides & Iglesias , C. mirandae Vovides, Pérez-Farr. & Iglesias , C. norstogii D.W.Stev. , C. vovidesii Pérez-Farr. & Iglesias ].... C. (C.) picipennis Tang, Skelley & Pérez-Farrera

- Dark elytral markings (when present) only along suture and laterally; pronotum generally shorter, PL/PW = 0.80–0.84..... 5

5(4). Color of pronotum and elytra similar; pronotum generally more quadrate; male genitalia with penile struts relatively long, length of penile strut relative to median lobe 2:1; setae at apex of parameres with greatest length <dorsal width of parameres; [Veracruz — C. tenuis ].............. C. (C.) sanchezae Tang, Skelley & Pérez-Farrera (? P. mexicana Santiago-Jiménez )

- Pronotum reddish brown contrasting with light brown of elytra; pronotum generally more trapezoidal, narrowing anteriorly; male genitalia with penile struts shorter, length of penile struts relative to median lobe 3:2; setae at apex of parameres with greatest length ≥ dorsal width of parameres; [Oaxaca — C. mixeorum Chemnick, T.J.Greg. & Salas-Mor. ]............................................................................ C. (C.) gregoryi Tang, Skelley & Pérez-Farrera

6(2). Male meso- and metatibiae each with medial subapical emargination ( Fig. 3G ); female abdominal segments weakly alutaceous, punctures and setae visible except on lateral quarters......................................................... 7

- Male tibiae lacking medial subapical emargination; female abdominal segments strongly alutaceous, punctures obscured across middle, setae reduced [Chiapas — C. alvarezii , C. mirandae , C. norstogi , C. vovidesii ].......................................................................................... C. (V.) chiapensis Tang, Skelley & Pérez-Farrera

7(6). Submentum of male and female with sparse patch of setae-bearing punctures, male with long setae projecting anteriorly; pronotal length to width (PL/PW) = 0.65–0.73; male genitalia more dorsoventrally compressed, median lobe nearly cylindrical; [Veracruz — C. mixeorum ]....................................... C. (V.) mixeorum Tang, Skelley & Pérez-Farrera

- Submentum of male and female with dense patch of setae-bearing punctures, male with long setae projecting laterally ( Figs. 4E–F ); PL/PW = 0.70–0.86; male genitalia laterally compressed, median lobe laterally flattened and distinctly curved in lateral view............................................................................................... 8

8(7). Pronotum shorter, wider, pronotal length to width (PL/PW) of males = 0.76–0.79, of females = 0.70–0.76; [Veracruz — C. tenuis ]............................... C. (V.) vazquezi Tang, Skelley & Pérez-Farrera (? P. tenuis Santiago-Jiménez )

- Pronotum longer, narrower, PL/PW of males = 0.81–0.86, of females = 0.78–0.82; [Chiapas — C. santillanii ]................................................................. C. (V.) chipjonesi Tang & Gomez Dominguez , new species

9(1). Pronotum anterior angles rounded ( Fig. 6A ), PL/PW = 0.68–0.74; in females, spermatheca short, length/width ratio <3.5, apical 1/3 wider than basal 1/3, insertion points of spermathecal and glandular ducts adjacent and in one shallow pit ( Fig. 4J ) [Chiapas — C. santillanii ]............................ Pharaxonotha perezi Tang & Gomez Dominguez , new species

- Pronotum anterior angles pointed, PL/PW = 0.71–0.79; in females, spermatheca more elongated, length/width ratio> 4, apical and basal 1/3 approx. equal in width; insertion points of spermathecal and glandular ducts separate and on a raised swelling, not in a pit [Chiapas — C. santillanii ]........................................................... Pharaxonotha sp.

Figures

FIGURE 2. Spermatheca of Pharaxonotha from Jalpan de Cerra, Querétaro, Mexico indicating the diagnostic structures and orientations used in descriptions and key.

FIGURE 3. Key characters of adults: base of head, pronotum and base of elytra, dorsal view: A) Pharaxonotha sp. collected from Ceratozamia tenuis; B) Ceratophila (C.) chemnicki; pronotal left lateral margins: C) Pharaxonotha sp. from Ceratozamia tenuis; D) Ceratophila (C.) sanchezae; E) C. (Vovidesa) chiapensis; right metatibiae of male individuals, posterior view: F) C. (C.) gregoryi; G) C. (V.) mixeorum; b: basal bead of elytra; g: longitudinal grooves; s: stridulatory files t: transverse groove. Scale bars = 0.2 mm.

FIGURE 4. Ceratophila chipjonesi male holotype: A–F: A–C) dorsal, lateral and ventral habitus; D–F) head dorsal, lateral and ventral views, arrow indicates tuff of setae projecting laterally from submentum; G) tegmen attached to median lobe, (top to bottom) ventral and lateral views; H) male genital capsule, ventral view; I) parameres of tegmen, ventral view; J) paramere, lateral view. Scale bars: white = 1 mm for A, B & C; brown = 0.5 mm for D, E & F; gray = 0.5 mm for G & H; black = 0.1 mm for I & J.

FIGURE 5. Ceratophila chipjonesi female: A–C) allotype dorsal, lateral and ventral habitus; D–F) head dorsal, lateral and ventral views; G) female genitalia, ventral view; H) spermatheca. Scale bars: white = 1 mm for A, B & C; brown = 0.5 mm for D, E & F; gray = 0.5 mm for G; black = 0.1 mm for H.

FIGURE 6. Pharaxonotha perezi (A–F: female holotype): A–C) dorsal, lateral and ventral habitus (male habitus with no discernable difference); D–F) head, dorsal, lateral and ventral views; G) tegmen attached to median lobe (top) genital capsule (bottom), ventral views; H) tegmen attached to median lobe, lateral view; I) parameres of tegmen, (top to bottom) ventral and lateral views; J) spermatheca; K) female genitalia, ventral view. Scale bars: white = 1 mm for A, B & C; brown = 0.5 mm for D, E & F; gray = 0.5 mm for G, H & K; black = 0.1 mm for I & J.