Revision of the genus Cenophengus LeConte, 1881 (Coleoptera, Phengodidae), with the description of four new species, new geographic records and a new synonymy

Abstract A taxonomic revision of the genus Cenophengus LeConte, 1881 (Coleoptera: Phengodidae) is provided, including new data on geographic ranges of the species. This is the first time this genus has been recorded for Belize and in Honduras. Four new species (C.gardunoi, C.saasil, C.tsiik and C.zuritai) are described and a new synonymy (C.guerrerensis, Zaragoza-Caballero, 1991 = C.major Wittmer, 1976) is established. The study includes a key to the 30 valid species, diagnoses, descriptions, photographs and distribution maps.


Introduction
The genus Cenophengus was described by LeConte (1881), based on C. debilis, a species from California, United States of America. LeConte took into account characters such convex in dorsal view, posterior edge convex with a small median notch or not, sides almost straight, anterior angles rounded, posterior angles rounded or acute; prosternal anterior margin sinuate; scutellum triangular, narrowed distally; each elytron 2.8 to 5.4 times wider than long, leaving the last 3 abdominal segments exposed, apex slightly swollen in dorsal view; hind wings with radial cell closed, r4 vein present or absent (if present: without touching the RP and the radial cell or touching the RP and the radial cell ), r3 vein present or absent, RP up to half as long as MP1+2, medial field may or may not contain seven main veins: MP3, MP4, CuA, CuA2, CuA3+4, AA1+2 and AA3+4; AA and AP3+4 well-marked to vestigial and cubito-anal cell open or closed; legs increasing in length posterad, tarsomeres simple without ventral combs, tarsomeres 1 and 2 of the prothoracic legs similar in length, tarsomere 3 shorter, tarsomeres 1, 2 and 3 of meso-and metathoracic legs decreasing in length, fourth tarsomere of all legs 1/3 as long as fifth; claws simple, without any teeth. Abdomen. Eight sternites visible, sternite 7 with sides subparallel, posterior margin sinuate; sternite 8 rhomboidal, with posterior margin notched; aedeagus with phallobase entirely sclerotised; median lobe cylindrical, rounded apically; flagellum not encircling median lobe at rest, about 1.5 times longer than median lobe; parameres symmetrical in dorsal view, slightly widened towards the middle, toothed on mesal side pre-apically, with long bristles separated by a distance at least 0.2 setae lengths. Antennae short ( Antennomere 1 is longer than antennomeres 2 and 3 combined; terminal maxillary palpomere shorter than or equal to preceding three combined ...29 29 Terminal maxillary palpomere shorter than preceding three combined; antennal rami 1.5 times respective antennomere ........C. zuritai sp. nov. (Fig. 33 Type locality. California, USA (Fig. 3). Type material examined. Holotype ♂: "Type /2813" "Cenophengus/ debilis Lec." "Cal." | MCZ, url: http:/insects.oeb.harvard.edu.
Remarks. Cenophengus debilis is morphologically similar to C. baios, but can be distinguished by the antennal rami length, branching of the hind wing and interantennal distance. In C. debilis, the branching of the anterior cubital veins (CuA) is present on the hind wing, whereas in C. baios, it is unbranched. The interantennal distance is wider than length of first antennomere in C. debilis, in C. baios, it is narrower than length of antennomere 1. Additionally, in C. debilis, the antennal rami are 1.5 times as long as the respective antennomere, whereas in C. baios, they are as long as the respective antennomere.
Diagnosis. Integument smooth and pronotum bicoloured (yellow-orange and dark brown); antennal rami are 1.5 times as long as the respective antennomere; clypeus totally sclerotised; anterior cubital veins (CuA) on hind wing branched; aedeagus with one spine at the inner apex of paramere.
Female and immatures. Unknown.  Remarks. Cenophengus brunneus is sister to C. villae (Vega-Badillo et al. 2021b), but can be distinguished by the interocular distance: in C. brunneus it is 3.5 times eye width, whereas in C. villae, it is 4.0 times longer. Additionally, in C. brunneus, the pronotal disc is convex, without a longitudinal carina, whereas in C. villae, it has a longitudinal carina.
Diagnosis. Body brown, integument chagreened, antennae less than twice the length of the pronotum, antennal rami 1.5 times the respective antennomere and each elytron 5.1 times as long as wide; aedeagus with three teeth at the inner apex of paramere.

Cenophengus ciceroi Wittmer, 1981
Remarks. Cenophengus ciceroi is sister to C. gorhami (Vega-Badillo et al. 2021b), but can be distinguished by the antennal rami length, interocular distance and the terminal maxillary palpomere. In C. ciceroi, the interocular distance is 1.5 times eye width, whereas in C. gorhami, it is twice longer. The terminal maxillary palpomere is as long as the preceding three combined in C. ciceroi; in C. gorhami, it is shorter than the preceding three combined. Additionally, in C. ciceroi, the antennal rami are twice as long as the respective antennomere, whereas in C. gorhami, they are 1.5 times as long as the respective antennomere.
Diagnosis. Integument chagreened, antennae less than twice the length of the pronotum, antennal rami twice as long as the respective antennomere, pronotum longer than wide and each elytron 3.3 times as long as wide; aedeagus with three teeth at the inner apex of paramere.
Female and immatures. Unknown. Distribution. USA (Fig. 3). Remarks. Cenophengus cuicatlaensis is morphologically similar to C. tsiik, but can be distinguished by the interocular distance and the terminal maxillary palpomere. In C. cuicatlaensis, interocular distance is twice as long as eye width, whereas in C. tsiik, it is 3 times as long as eye width. Terminal maxillary palpomere is longer than the preceding three combined in C. cuicatlaensis, in C. tsiik, it is shorter than the preceding three combined.

Cenophengus cuicatlaensis
Diagnosis. Integument chagreened, antennae long more than twice the length of pronotum, antennal rami twice as long as the respective antennomere, pronotum longer than wide and each elytron 3.8 times as long as wide; aedeagus with three teeth at the inner apex of paramere.
Female and immatures. Unknown. Distribution. Mexico: Oaxaca (Fig. 3). Remarks. Cenophengus gardunoi is morphologically similar to C. major, but can be distinguished by the integument and r3 vein. In C. gardunoi, the integument is chagreened, whereas in C. major, it is smooth; the r3 vein is absent in C. gardunoi, whereas in C. major, it is present.

Cenophengus gardunoi
Diagnosis. This species can be distinguished by the chagreened integument, antennae long, more than twice the length of pronotum, antennal rami 3 times the respective antennomere and each elytron 4.4 times as long as wide, with two longitudinal costae and aedeagus with three teeth at the inner apex of paramere.
Diagnosis. Integument chagreened, antennae long, more than twice the length of pronotum, antennal rami twice as long as the respective antennomere and elytra barely reaching the middle of the metasternum, each elytron 3.1 times as long as wide; aedeagus with three teeth at the inner apex of paramere.
Diagnosis. Integument smooth, long antennae more than twice the length of pronotum, antennal rami 1.5 times the respective antennomere and each elytron 4.7 times as long as wide with whitish colouration at the apex; aedeagus with three teeth at the inner apex of paramere.
Diagnosis. Integument chagreened, antennae long, more than twice the length of pronotum, antennal rami twice as long as the respective antennomere, each elytron 2.6 times as long as wide; aedeagus with three teeth at the inner apex of paramere.
Female and immatures. Unknown. Distribution. Mexico: Durango (Fig. 3). Remarks. Cenophengus huatulcoensis is morphologically similar to C. baios, but can be distinguished by its shorter size, interantennal and interocular distances. In C. hualcoensis, the interantennal distance is equal to the length of the antennomere 1, whereas in C. baios, it is shorter. The interocular distance is 3.0 times longer than eye width in C. hualcoensis, in C. baios, it is 3.5 times longer. Additionally, in C. hualcoensis, the antennal rami are twice as long as the respective antennomere, whereas in C. baios, they are as long as the respective antennomere.

Cenophengus huatulcoensis
Diagnosis. Integument smooth, antennae less than twice the length of the pronotum, antennal rami lanceolate, twice as long as respective antennomere, pronotum as long as wide and each elytron 3.1 times as long as wide; aedeagus with one spine at the inner apex of paramere.
Immatures and females. Unknown. Distribution. Mexico: Oaxaca (Fig. 3). Remarks. Cenophengus kikapu is morphologically similar to C. sonoraensis, but can be distinguished by the width of the head and the terminal maxillary palpomere.

Cenophengus kikapu
In C. sonoraensis, the head is almost as wide as the pronotum, whereas in C. kikapu, the head is wider than the pronotum. In addition, the terminal maxillary palpomere is as long as the preceding three combined in C. sonoraensis, whereas in C. kikapu, it is longer than the preceding three combined.
Diagnosis. Head almost as wide as pronotum, integument chagreened, antennae less than twice the length of the pronotum, antennal rami twice as long as respective antennomere, terminal maxillary palpomere as long as preceding three combined, each elytron 3.6 times as long as wide; aedeagus with three teeth at the inner apex of paramere.
Female and immatures. Unknown. Distribution. Mexico: Coahuila (Fig. 3). Remarks. Cenophengus longicollis is morphologically similar to C. xiinbali, but can be distinguished by the interocular distance and the terminal maxillary palpomere. In C. longicollis, the interocular distance is 3.5 times longer than eye width, whereas in C. xiinbali, it is 2.5 times longer. The terminal maxillary palpomere is longer than the preceding three combined in C. longicollis, whereas in C. xiinbali, it is as long as the preceding three combined.
Female and immatures. Unknown. Distribution. USA: Texas (Fig. 3). Remarks. Cenophengus magnus is sister to C. major (Vega-Badillo et al. 2021b), but can be distinguished by the elytral length and r3 vein. In C. magnus, each elytron is 4 times as long as wide, whereas in C. major, they are almost 4.5 times as long as wide; the r3 vein is absent in C. magnus, whereas in C. major, it is present.
Diagnosis. Integument smooth, antennae long, more than twice the length of pronotum antennal rami, 3 times the respective antennomere, scutellum almost quadrangular, with small notch on posterior margin and each elytron 4 times as long as wide, with one longitudinal costa; aedeagus with three teeth at the inner apex of paramere.
Female and immatures. Unknown. Remarks. We synonymise C. guerrerensis with C. major, based on the observation of holotypes, being the body shape and total body length, as well as the maxillary palps and wing venation particularly important characters for its synonymisation. C. major is sister to C. magnus (Vega-Badillo et al. 2021b), but can be distinguished by the elytral length and r3 vein. In C. magnus, each elytron is 4 times as long as wide, whereas in C. major, they are almost 4.5 times as long as wide; the r3 vein is absent in C. magnus, whereas in C. major, it is present.
Diagnosis. Integument smooth, antennae long, more than twice the length of pronotum, antennal rami lanceolate in lateral view, 3.1 times the respective antennomere and each elytron 4.5 times as long as wide; aedeagus with three teeth at the inner apex of paramere.
Diagnosis. Head almost as wide as the pronotum, integument chagreened, antennae long, more than twice the length of pronotum, antennal rami twice as long as the respective antennomere; pronotum mottled with darker brown spots; each elytron 4.0 times as long as wide; aedeagus with three teeth at the inner apex of paramere.

Remarks.
Cenophengus mboi is morphologically similar to C. predregalensis, but can be distinguished by the colour of the body and terminal maxillary palpomere. In C. mboi, the body is dark brown, whereas in C. pregalensis, it is dark brown and the pronotum yellow-orange. Terminal maxillary palpomere is as long as the preceding three combined in C. mboi, in C. pedregalensis, it is longer than the preceding three combined.
Diagnosis. Body black, integument chagreened, antennae long, more than twice the length of pronotum, antennal rami twice as long as the respective antennomere, terminal maxillary palpomere is as long as the preceding three combined and each elytron 4.3 times as long as wide; aedeagus with three teeth at the inner apex of paramere.
Female and immatures. Unknown. Distribution. Mexico: Hidalgo (Fig. 19). Remarks. Cenophengus mumui is in a clade with C. munizi and C. huatulcoensis (Vega-Badillo et al. 2021b), but can be distinguished from C. munizi by the shape and colour of the head. In C. mumui, the head is square and brown, whereas in C. munizi, it is rectangular-shaped. Additionally, in C. mumui, the antennal rami are 1.5 times as long as the respective antennomere, whereas in C. munizi, they are twice as long as the respective antennomere. Finally, C. mumui can be distinguished from C. huatulcoensis by the interantennal distance and interocular distance. In C. huatulcoensis, the interantennal distance is equal to the length of antennomere 1, whereas in C. mumui, it is less than the length of antennomere 1. The interocular distance is 2 times eye width in C. mumui, in C. huatulcoensis, it is 3 times eye width.

Cenophengus mumui Vega-Badillo et al. 2021
Diagnosis. Body yellow, except for head brown, integument smooth, antennae long more than twice the length of pronotum, antennal rami 1.5 times the respective antennomere, pronotum as long as wide and each elytron 4.3 times as long as wide; aedeagus with one spine at the inner apex of paramere.
Immatures and females. Unknown. Distribution. Mexico: San Luis Postosí and Tamaulipas (Fig. 19). Remarks. Cenophengus munizi is in a clade with C. mumui and C. huatulcoensis (Vega-Badillo et al. 2021b), but can be distinguished from C. mumui by the shape and colour of the head and interantennal distance. Cenophengus munizi exhibits a rectangular-shaped head, which is yellow-brown coloured like the rest of the body, whereas in C. mumui, it is square and brown. In C. munizi, the interantennal distance is equal to the length of antennomere 1, whereas in C. mumui, it is less than the length of antennomere 1. Additionally, in C. munizi, the antennal rami are twice as long as the respective antennomere, whereas in C. mumui, they are 1.5 times as long as the respective antennomere. Finally, C. munizi can be distinguished from C. huatulcoensis by the interocular distance. The interocular distance is 2 times eye width in C. mumui, in C. huatulcoensis, it is 3 times eye width.
Diagnosis. Integument smooth, head almost as wide as the pronotum, antennae long, more than twice the length of pronotum, antennal rami twice as long as respective antennomere, each elytron 6 times as long as wide; aedeagus one with spine at the inner apex of paramere.
Immatures and females. Unknown. Distribution. Mexico: Hidalgo (Fig. 19). Remarks. Cenophengus niger is morphologically similar to C. howdeni, but can be distinguished by the length of antennomere 1 and the diameters of the punctures. In C. niger, antennomere 1 is equal to the length of antennomeres 2 and 3 combined, whereas in C. howdeni, it is shorter than antennomeres 2 and 3 combined. In C. niger, the punctures are twice as long as eye facets and separated by approximately 0.2 punctured diameters, whereas in C. howdeni, they are as long as eye facets and separated by approximately 1 punctured diameter.
Diagnosis. Integument chagreened, head less wide than pronotum, antennae less than twice the length of the pronotum, antennal rami twice as long as the respective antennomere and each elytron 3.5 times as long as wide; aedeagus with three teeth at the inner apex of paramere.
Female and immatures. Unknown. Distribution. Costa Rica: Monteverde, Heredia and Puntarenas (Fig. 19). Remarks. Cenophengus pallidus is sister to C. sonoraensis (Vega-Badillo et al. 2021b), but can be distinguished by the colour of the body and the interocular distance. In C. pallidus, body is yellow, whereas in C. sonoraensis, it is pale brown. The interocular distance is 1.5 times eye width in C. pallidus, in C. sonoraensis, it is twice eye width. Additionally, in C. pallidus, the pronotal disc has a longitudinal carina, whereas in C. sonoraensis, it is weakly elevated dorsally forming a small depression in the basal part of each side.
Diagnosis. Integument chagreened, head wider than the pronotum, antennae short, less than twice the length of the pronotum, antennal rami twice as long as the respective antennomere and each elytron 3.5 times as long as wide; aedeagus with three teeth at the inner apex of paramere.
Female and immatures. Unknown. Distribution. USA: Texas; Mexico: Nuevo León (Fig. 19). Remarks. Cenophengus pedregalensis is morphologically similar to C. mboi, but can be distinguished by the colour of the body and the terminal maxillary palpomere. In C. predregalensis, body is dark brown and pronotum yellow-orange, whereas in C. mboi, it is dark. The terminal maxillary palpomere is longer than the preceding three combined in C. pedregalensis, in C. mboi, it is as long as the preceding three combined.
Diagnosis. Body dark brown with pronotum yellow-orange, integument chagreened, antennae long, more than twice the length of pronotum, antennal rami twice as long as the respective antennomere, terminal maxillary palpomere is longer than the preceding three combined and each elytron 4.5 times as long as wide; aedeagus with three teeth at the inner apex of paramere.
Female and immatures. Unknown. Distribution. Mexico: Mexico City (Fig. 19). Additional material examined. "MEXICO: Ciudad de Mexico/Jardín Botánico,/19°19'10" N 99° 11'37.25 Remarks. Cenophengus punctatissimus is morphologically similar to C. mboi, but can be distinguished by the interocular distance. In C. punctatissimus, the interocular distance is 2.5 times eye width, whereas in C. mboi, it is 3 times eye width. Additionally, in C. punctatissimus, the posterior radial vein length is 5.3 times less than the length of MP1+2, whereas in C. pedregalensis, it is twice less than the length of MP1+2.
Diagnosis. Body dark brown, integument chagreened, head less wide than the pronotum, antennae long, more than twice the length of pronotum, antennal rami twice as long as the respective antennomere and each elytron 5.4 times as long as wide; aedeagus with three teeth at the inner apex of paramere.
Female and immatures. Unknown. Distribution. Mexico: San Luis Potosí (Fig. 19). Remarks. Cenophegus saasil is morphologically similar to C. wittmeri, but can be distinguished by pronotum colouration and r3 vein. In C. saasil, the pronotum colouration is uniform, whereas in C. wittmeri, it is dark brown near mid-line; the r3 vein is present in C. wittmeri and absent in C. saasil.

Cenophegus saasil
Diagnosis. Body pale yellow, integument chagreened, head as wide as the pronotum, antennae long, more than twice the length of pronotum, antennal rami twice as long as the respective antennomere and each elytron 4.6 times as long as wide; aedeagus with three teeth at the inner apex of paramere.
Description. Male. Body length 9.50 mm, maximum body width 0.90 mm (pronotum). Body pale yellow, except for the antennae and stripe on pronotum brown (Fig. 26A, B). Head. Wider (0.90 mm) than long (0.65 mm) (Fig. 26C), at eye level, as wide as the pronotum, integument chagreened, punctures twice as long as eye facets and separated by approximately 1 punctured diameter, each puncture bearing a yellow seta; interantennal distance (0.06 mm) less than the length of antennomere 1 (0.24 mm); eyes 1/2 as long as head in lateral view, longer (0.41 mm) than wide (0.21 mm); interocular distance (0.42 mm) twice as long as eye width; antennae long (3.10 mm) more than twice the length of pronotum; antennomere 1 (0.24 mm) longer than next two combined, antennomere 3 cup-shaped, 4 to 11 about equal in length (0.30 mm), 12 (terminal) (0.33 mm), antennal rami lanceolate in lateral view, twice as long as the respective antennomere; maxillary palpomeres of the holotype lost; labial palpomere 1 (0.03 mm). Thorax. Pronotum longer (1.10 mm) than wide (0.90 mm) (Fig. 26D); integument chagreened, punctures twice as long as facets and separated by approximately 1.5 punctured diameters, each puncture bearing a yellow seta, disc convex, weakly elevated dorsally, forming a small depression in the basal part of each side, posterior margin curved with middle notch, sides almost straight, anterior angles rounded and posterior angles acute; mesosternal suture incomplete; scutellum of the holotype lost; each elytron 4.6 times as long (3.40 mm) as wide (0.74 mm), convex, with longitudinal costae, elytral apex rounded; hind wings with posterior radial vein (RP) length twice less than the length of MP1+2, radial cell closed, r3 vein absent, r4 vein developed (reaching the radial cell), those of the anterior anal and posterior anal sectors, present (Fig. 26E). Legs: tarsomeres 1 and 2 of the prothoracic legs with a similar length and tarsomere 1 of meso-and metathoracic legs is longer than 2. Abdomen. Integument shiny, punctured, with long dense setae, sternite 7 with margin sinuate, sternite 8 with margin notched; aedeagus with three teeth at the inner apex of paramere ( Fig. 26F-H).
Female and immatures. Unknown. Distribution. Honduras (Fig. 19). Etymology. The term sáasil means glow in the Maya language, which is spoken in Honduras. Remarks. Cenophengus sonoraensis is sister to C. pallidus (Vega-Badillo et al. 2021b), but can be distinguished by the colour of the body and the interocular distance. In C. sonoraensis, it has a pale brown body, whereas in C. pallidus, it is yellow. The interocular distance is twice as long as eye width in C. sonoraensis, in C. pallidus, it is 1.5 longer than eye width. Additionally, in C. sonoraensis, disc weakly elevated dorsally, forming a small depression in the basal part of each side, whereas in C. pallidus, it has a longitudinal carina.

Cenophengus sonoraensis Zaragoza-Caballero, 2008
Diagnosis. Body pale brown, integument chagreened, head wider than the pronotum, antennae less than twice the length of the pronotum, antennal rami twice as long as the respective antennomere and each elytron 4.1 times as long as wide.
Female and immatures. Unknown. Distribution. Mexico: Sonora (Fig. 19). Remarks. Cenophengus tsiik is morphologically similar to C. cuicatlaensis, but can be distinguished by the interocular distance and the terminal maxillary palpomere. In C. tsiik, interocular distance is 3 times eye width, whereas in C. cuicatlaensis, it is twice as long as eye width. Terminal maxillary palpomere is shorter than the preceding three combined in C. tsiik, in C. cuicatlaensis, it is longer than the preceding three combined.

Cenophengus tsiik
Diagnosis. Integument chagreened, head almost as wide as the pronotum, antennae less than twice the length of the pronotum, antennal rami 1.5 times the respective and antennomere, each elytron 2.8 times as long as wide; aedeagus with three teeth at the inner apex of paramere.
Description. Male. Body length 5.50 mm, maximum body width 0.65 mm (pronotum). Body dark brown, except for the antennae buccal parts, legs and the two last sternites are pale brown to yellow (Fig. 28A, B). Head. Wider (0.68 mm) than long (0.55 mm) (Fig. 28C), at eye level, almost as wide as the pronotum (0.65 mm), integument chagreened, punctures twice as long as eye facets and separated by approximately 0.5 punctured diameters, each puncture bearing a yellow-brown seta; interantennal distance (0.09 mm) less than the length of antennomere 1 (0.18 mm); eyes 1/2 as long as head in lateral view, longer (0.30 mm) than wide (0.13 mm); interocular distance (0.40 mm) 3 times eye width; antennae short (1.58 mm less than twice the length of the pronotum; antennomere 1 (0.18 mm) is longer than the next two combined (0.10 mm), antennomere 3 cup-shaped, 4 (0.10 mm) shorter than following antennomeres, 5 to 11 about equal in length (0.15 mm), 12 (terminal) (0.17 mm), antennal rami lanceolate in lateral view, 1.5 times the respective antennomere; terminal maxillary palpomere robust, securiform (0.25 mm), shorter than the preceding three combined; terminal labial palpomere spindle-shaped (0.09 mm), 3 times as long as preceding one (0.03 mm). Thorax. Pronotum longer (0.80 mm) than wide (0.65 mm) (Fig. 28D); integument chagreened, punctures twice as long as eye facets and separated by approximately 1 punctured diameter, each puncture bearing a yellow-brown seta, disc convex, with a longitudinal carina in posterior portion of pronotum strongly visible, with a length equal to the median length of the pronotum, posterior margin curved with middle notch, sides almost straight, anterior and posterior angles rounded; mesosternal suture complete; scutellum with posterior margin rounded; each elytron 2.8 times as long (1.12 mm) as wide (0.40 mm), convex, without longitudinal costae, elytral apex rounded; hind wings with posterior radial vein (RP) length 5 times less than the length of MP1+2, radial cell closed, r3 vein absent, r4 vein developed (reaching the radial cell), those of the anterior anal and posterior anal sectors, slightly evident (Fig. 28E). Legs: tarsomere 1 of pro-, meso-and metathoracic legs is longer than 2. Abdomen. Integument shiny, punctured, with long dense setae, sternite 7 with margin sinuate, sternite 8 with margin notched; aedeagus with three teeth at the inner apex of paramere ( Fig. 28F-H).
Female and immatures. Unknown. Distribution. Belize (Fig. 19). Etymology. The term "tsiik" means honour in the Maya language, which is spoken in some regions of Belize. Remarks. Cenophengus tupae is morphologically similar to C. howdeni, but can be distinguished by the length of antennomere 1, the pronotal disc and interocular distance. In C. tupae, antennomere 1 is longer than the next two combined, whereas in C. howdeni, it is shorter than the next two combined. The pronotal disc is convex, weakly elevated dorsally, forming a small depression in the basal part of each side, in C. howdeni it has a groove along mid-line. The interocular distance is 3.0 times eye width in C. howdeni, in C. tupae, it is twice as long as eye width.

Cenophengus tupae
Diagnosis. Body brown except for antennae yellow-brown, integument chagreened, antennae long, more than twice the length of pronotum, antennal rami 3 times as long as the respective antennomere, head almost as wide as the pronotum and each elytron 4.1 times as long as wide; aedeagus trilobed with three teeth at the inner apex of paramere.
Female and immatures. Unknown. Distribution. Mexico: San Luis Potosí (Fig. 19). Remarks. Cenophengus villae is sister to C. brunneus (Vega-Badillo et al. 2021b), but can be distinguished by the interocular distance: in C. villae, it is 4 times eye width, whereas in C. brunneus, it is 3.5 times longer. Additionally, in C. villae, the pronotal disc has a longitudinal carina, whereas in C. brunneus, the disc is without a longitudinal carina.

Cenophengus villae
Diagnosis. Body dark brown, integument chagreened, antennae less than twice the length of the pronotum, antennal rami 1.5 times the respective antennomere and each elytron 4.3 times as long as wide.
Redescription. Male. Body length 4.20 mm, maximum body width 0.51 mm (pronotum). Body dark brown, except for legs yellowish (Fig. 30A). Head. Wider (0.65 mm) than long (0.50 mm) (Fig. 30B), at eye level, less wide than the pronotum, integument chagreened, punctures twice as long as eye facets and separated by approximately 1 punctured diameter, each puncture bearing a brown seta; interantennal distance (0.05 mm) less than the length of antennomere 1 (0.13 mm); eyes 1/2 as long as head in lateral view, longer (0.28 mm) than wide (0.15 mm); interocular distance (0.70 mm) 4 times eye width; antennae short (1.50 mm) less than twice the length of the pronotum; antennomere 1 (0.13 mm) as long as the next two combined, antennomere 3 cup-shaped, 4 (0.11 mm) shorter than following antennomeres, 5 to 11 about equal in length (0.15 mm), 12 (terminal) (0.20 mm), antennal rami lanceolate in lateral view, 1.5 times the respective antennomere; terminal maxillary palpomere robust, securiform (0.40 mm), as long as the preceding three combined; terminal labial palpomere spindle-shaped (0.06 mm), 3 times as long as preceding one (0.02 mm). Thorax. Pronotum longer (0.70 mm) than wide (0.51 mm) (Fig. 30C); integument chagreened, punctures twice as long as eye facets and separated by approximately 1 punctured diameter, each puncture bearing a brown seta, disc convex, with a longitudinal carina in posterior portion of pronotum strongly visible, with a length that does not reach the median length of the pronotum, posterior margin curved, sides almost straight, anterior and posterior angles rounded; mesosternal suture complete; scutellum with posterior margin rounded; each elytron 4.3 times as long (1.64 mm) as wide (0.38 mm), convex, without longitudinal costae, elytral apex rounded; hind wings with posterior radial vein (RP) length 5 times less than the length of MP1+2, radial cell closed, r3 vein present, r4 vein reduced (not reaching the RP or the radial cell, those of the anterior anal and posterior anal sectors, evident (Fig. 30D). Legs: tarsomeres 1 and 2 of pro-and mesothoracic legs with a similar length, tarsomere 1 of metathoracic legs is longer than 2. Abdomen. Integument shiny, punctured, with long dense setae, sternite 7 with margin sinuate, sternite 8 with margin notched; aedeagus of the holotype lost.
Female and immatures. Unknown. Distribution. Mexico: Veracruz (Fig. 19). Remarks. Cenophengus wittmeri is morphologically similar to C. marmoratus, but can be distinguished by the colour of the body and the terminal maxillary palpomere. In C. wittmeri, its body is brown, except for the middle part of the pronotum that is dark brown, whereas in C. marmoratus, it is yellow or pale brown, the pronotum partially interrupted by darker brown spots. The terminal maxillary palpomere is as long as the preceding three combined in C. wittmeri, in C. marmoratus, it is shorter than the preceding three combined. Additionally, in C. wittmeri, the posterior radial vein length is twice less than the length of MP1+2, whereas in C. marmoratus, it is 1.6 times less than the length of MP1+2.

Cenophengus wittmeri
Diagnosis. Body brown, except for middle part of pronotum, integument chagreened, head almost as wide as the pronotum, antennae long, more than twice the length of pronotum, antennal rami twice as long as the respective antennomere and each elytron 3.7 times as long as wide; aedeagus with three teeth at the inner apex of paramere.
Female and immatures. Unknown. Distribution. Mexico: Puebla, Hidalgo and Veracruz (Fig. 19). Remarks. Cenophengus xiinbali is morphologically similar to C. longicollis, but can be distinguished by the interocular distance and terminal maxillary palpomere. In C. xiinbali, the interocular distance is 3.5 times eye width, whereas in C. longicollis, it is 3 times longer. The terminal maxillary palpomere is as long as the preceding three combined in C. xiinbali, whereas in C. longicollis, it is longer than the preceding three combined.
Diagnosis. Integument chagreened, antennae long, more than twice the length of pronotum, antennal rami twice as long as the respective antennomere, terminal maxillary palpomere as long as the preceding three combined and each elytron 4.1 times as long as wide; aedeagus with three teeth at the inner apex of paramere.
Redescription. Male. Body length 8.15-8.30 mm, maximum body width 0.90-0.93 mm (pronotum). Body brown, except for pronotum, legs and two last abdominal Remarks. Cenophengus zuritai is morphologically similar to C. xiinbali, but can be distinguished by the interocular distance and terminal maxillary palpomere. In C. zuritai, the interocular distance is 3 times eye width, whereas in C. xiinbali, it is 2.5 times longer. The terminal maxillary palpomere is shorter than the preceding three combined in C. zuritai, whereas in C. xiinbali, it is as long as the preceding three combined.
Diagnosis. Head orange-brown, pronotum orange, integument chagreened, head a little wider than the pronotum, antennae long, more than twice the length of

Discussion
The genera Cenophengus and Phengodes (Zaragoza-Caballero and Pérez-Hernández 2014) are the richest genera within the family Phengodidae. Cenophengus species are distributed in the Nearctic and Neotropical regions, mainly in the mountainous areas of the Mexican Transition Zone (sensu Morrone et al. 2017), where its highest diversity is found (Vega-Badillo et al. 2021b). In this work, we describe four new species, three of which are distributed in the mountainous areas of Central America (Chiapas Highlands and Central American biogeographic provinces). This suggests that these species may show high levels of endemism, perhaps due to low vagility caused by the presence of neotenic females which reduces the capabilities to disperse and colonise new habitats (Bocak et al. 2008).
Some intraspecific variation in colouration has been observed in some species of Cenophengus, particularly in C. pedregalensis, C. dedilis and C. major, which are amongst the few species that have been widely collected, compared to other species for which only the holotype is available. One of the insights derived from observation of several populations of C. pedregalensis and C. major, however, is that, despite variation in colouration, wing venation remains comparatively constant intraspecifically, being useful for discerning between species within the genus (Vega-Badillo et al. 2021a). These observations are amenable to a morphometric analysis in the future, including extensive taxonomic and population sampling, as well as analysis of variation both in other structures and at the genetic level.
Taxonomy is essential for biodiversity knowledge and a crucial part of ecosystem conservation. It is necessary to implement an adequate sampling programme to explore the distributional patterns of Cenophengus species and detect the existence of possible areas of endemism. These could contribute to the identification of areas suitable for biodiversity conservation.