Cymatodera gerstmeieri Burke & Rifkind

Burke, Alan F., Rifkind, Jacques & Zolnerowich, Gregory, 2015, Four new species of Cymatodera Gray from central and southern Mexico (Coleoptera, Cleridae, Tillinae), ZooKeys 513, pp. 105-121 : 114-115

Taxon classification Animalia Coleoptera Cleridae

Cymatodera gerstmeieri Burke & Rifkind sp. n. Figs 3, 8, 13, 18, 25, 27

Type material

(n = 8): Holotype, red labeled, male: Mexico, Chiapas, El Aguacero, 680 m, 17-VI-1990, at light, R. A. Cunningham; holotype deposited in CSCA. Paratypes, yellow labeled: 4 males, 2 females: same data as holotype (JNRC), except 2 males and 1 female collected on 16-VI-1990, and 1 male collected on 01-IX-1990; 1 female: Mexico Chiapas, Aguacero, 16 km W Ocoz[ocuautla], 1-7-VII-1986, 2500', J. E. Wappes (JEWC).

Differential diagnosis.

Cymatodera gerstmeieri is similar to a number of New World tilline species that share a testaceous to ferrugineous integument and a median, dark fascia on the elytral ground; those closest include Cymatodera mitae Burke, Bogcia disjuncta Barr, and Cymatodera insignis Schenkling. The new species can be separated from the former as follows: male specimens of Cymatodera gerstmeieri have the eleventh antennomere medially depressed, acuminate posteriorly, and approximately 2 × longer than tenth antennomere (Fig. 8), while males of Cymatodera mitae have the eleventh antennomere cylindrical in shape, rounded posteriorly, and approximately 2.5 –3× the length of tenth antennomere. Furthermore, males of Cymatodera gerstmeieri have a feebly developed longitudinal carina on the first ventrite, but lack a carina on the second ventrite (Fig. 27), whereas males of Cymatodera mitae have a well-developed longitudinal carina on the first ventrite, but also a somewhat less developed carina on the second (Fig. 28). The females of both species lack these carinae, but can be distinguished by the presence of a fuscous macula located on each elytral humeral angle in Cymatodera mitae , absent in Cymatodera gerstmeieri . The feebly to moderately serrate antennomeres 4-10 of Cymatodera gerstmeieri (Fig. 8) will easily separate it from Bogcia disjuncta , which has strongly serrate antennae. Cymatodera gerstmeieri somewhat recalls the Central American species Cymatodera insignis , with which it shares similar integumental color, antennal structure, and a median, slightly oblique, dark fascia. However, Cymatodera insignis bears a dark macula on the humeral angles, a longitudinal black macula at the posterolateral margin of the pronotum on either side, and has the posterolateral margins of the elytral ground narrowly darkened. These markings are absent in Cymatodera gerstmeieri .

Description.

Holotype male. Moderately small, rather robust, metathoracic wings complete, TL = 10.2 mm. Color: head, pronotum, prosternum, mesosternum ferrugineous-brown, the rest of the body uniformly testaceous brown. Each elytron with a fuscous, irregular fascia near the mid-length, extending from the elytral suture to the eighth row of striae, but not reaching the epipleural fold (Fig. 3).

Head: HL = 1.2 mm, HW = 1.85 mm. Measured across eyes wider than pronotum; surface feebly rugose, shiny; frons bi-impressed; moderately, coarsely punctate; vested with short, recumbent setae interspersed with some erect, stiff setae on and behind eyes; eyes rather rounded, moderately large, slightly longer than wide, feebly emarginate in front, bulging laterally. Antennae reaching posterior margin of pronotum; second antennomere 0.75 × longer than third antennomere, antennomeres 3-10 subequal in length; antennomeres 2-3 subcylindrical; fourth antennomere feebly serrate; antennomeres 5-10 moderately serrate; last antennomere flattened apically, posterior margin acuminate, about 2 × the length of tenth antennomere (Fig. 8).

Thorax: PL = 2.9 mm, PW = 1.5 mm. Pronotum rugose; moderately punctate; anterior margin as wide as middle; sides feebly constricted subapically; slightly more constricted behind middle; disc flat, very feebly impressed in front of middle; subbasal tumescence absent; surface clothed with moderately long, semirecumbent setae interspersed with some long, erect setae. Prosternum sparsely vested, feebly punctate. Mesosternum convex; surface shiny, moderately, shallowly punctate. Metasternum with surface rugulose, shiny, moderately, shallowly puncticulate.

Legs: Moderately vested with semierect and some recumbent setae; femora puncticulate, rugulose; tibia moderately punctate, rugulose.

Elytra: EL = 6.9 mm, EW = 4.4 mm. Broader than pronotum; humeri pronounced, rounded; sides subparallel, widest portion behind posterior third; disc flattened above; surface moderately rugulose; apices rounded, feebly dehiscent; elytral declivity gradual; integument clothed with short, semierect setae intermixed with fewer long, erect setae; surface bearing coarse punctation arranged in regular striae that gradually become smaller and shallower on posterior half, punctation not reaching elytral apex; interstices at elytral base about 1.2 × the width of punctation.

Abdomen: Ventrites 1-5 rugulose, moderately, finely punctate, clothed with short, pale, fine, recumbent setae. First ventrite rather convex, subquadrate, conspicuously elevated at posterior 1/4 with a transverse, arcuate carina which does not attain posterolateral angles (Fig. 27). Fifth ventrite (Fig. 13) feebly convex; subquadrate in shape; surface shiny, moderately, shallowly, finely punctate; lateral margins oblique, somewhat arcuate; posterolateral angles rounded; posterior margin feebly, broadly emarginate. Sixth ventrite (Fig. 13) reduced; broader than long; subtriangular; lateral margins oblique, arcuate; hind margin moderately acuminate; surface feebly convex, shiny, moderately, finely, shallowly puncticulate. Fifth tergite subtriangular in shape, rugulose; lateral margin moderately oblique, posterior margin truncate. Sixth tergite subtriangular, broader than long; lateral margins strongly oblique, feebly arcuate; converging posteriorly; extending beyond apical margin of sixth ventrite.

Aedeagus 1.2 mm long; feebly sclerotized; wide; ratio of length of paramere to whole tegmen 0.45:1; tegmen partially covering phallus; parameres subtriangular; lateral margins obtuse, strongly oblique, pointed distally; phallobase wide; phallic plate armed with two long rows of moderately large denticles along dorsal and distal margins; phallobasic apodeme slender, somewhat shorter than endophallic struts; phallobasic struts slender throughout their length, 1.5 × the length of phallobasic apodeme (Fig. 25).

Females can be distinguished from males based on the structure of the pygidium. The sixth ventrite and the sixth tergite are broadly rounded posteriorly in females (Fig. 18). Other characters are constant in both sexes.

Variation.

Length of males ranges from 8.7-10.2 mm; length of females from 9.5-13.1 mm. The elytral fascia is slightly variable in width, extending from the elytral suture to the epipleural fold in one male and one female, but incomplete in remaining individuals. Two males and one female in the type series have slightly paler elytra than the male holotype.

Distribution.

All specimens in the type series were collected in the locality of El Aguacero, approximately 10 miles northwest of Ocozocuautla, Chiapas, Mexico. The elevation at the type locality is approximately 650 m and the vegetation is predominantly tropical deciduous forest (Fig. 29).

Etymology.

We name this beetle for Prof. Dr. Roland Gerstmeier (Technische Universität München, Germany), in recognition of his many contributions to the study of Cleridae .