Canadian Journal of Arthropod Identification
 
 

The Cantharidae of Eastern Canada and Northeastern United States
CJAI 25 February 28, 2014
doi:10.3752/cjai.2014.25
urn:lsid:zoobank.org:pub:0D1AF9FE-8898-48CF-B031-4A3783079C69

G. Pelletier & C. Hébert

| Abstract | Introduction | Descriptions of Species | Checklist | Family Cantharidae | Identification Key | Synopsis of Taxa | Acknowledgments | References | PDF | Cite |

 
 

 

SYNOPSIS OF SUBFAMILIES, TRIBES AND GENERA OF CANTHARIDAE

(Based on Ramsdale (2002))

 

Subfamily CANTHARINAE

Frontoclypeal suture absent; apical maxillary palpomere bilaterally symmetrical. Lateral pronotum margin entire; elytra elongate. Seventh abdominal sternite of males with posterior margin entire and eighth abdominal sternite small and subtriangular; phallobase reduced, most membranous, with two lateral sclerites; lateral lobe large and strongly sclerotized; median lobe membranous. Female genitalia with coxites well developed, terminating in a setose stylus; proctiger typically more or less triangular, well developed and sclerotized, membranous; paraprocts well developed; valvifer well developed and sclerotized.

 

Tribe CANTHARINI

Head well visible from above but not constricted behind eyes, with gular suture widely separated. Pronotum slightly convex anteriorly, concealing the neck. Paired lateral glandular pores on abdominal tergites small, inconspicuous. Five genera are represented in our region.

Genus Atalantycha Kazantsev
(Cantharis (Ancistronycha): McKay-Fender (1950))

Third tarsomere emarginated, insertion of fourth tarsomere apical. Anterior claws of all tarsi invariably with a short triangular basal tooth. Three species are represented in our region.

 

Genus Cantharis Linnaeus

Third tarsomere emarginated, insertion of fourth tarsomere apical. Anterior mesotarsal and metatarsal claws entire or with a small basal blunt tooth. Male genitalia with laterophyses separated. Eight species are represented in our region.

 

Genus Pacificanthia Kazantsev

Head reddish orange. Pronotum nearly subquadrate or slightly transverse, much narrower than elytra, about 1.1X as wide as long, yellowish red. Elytra dark brown to black. Third tarsomere emarginate, insertion of fourth tarsomere pre-apical, claws simple. Two species are represented in our region.

 

Genus Rhagonycha Eschscholtz

Length 7.5 mm or less (except for R. fulva Scop.). Pronotum usually wider at basal third. Third tarsomere simple, not emarginated at apex, insertion of fourth tarsomere apical. More than 31 species are represented in our region.

This is the most difficult group of cantharids to identify because colour can vary considerably within a species and it is thus usually necessary to use other morphological features to separate species. The clypeus margin has four different shapes: emarginate at middle with lateral margins oblique, biarcuate, flat or sinuate. Relative eye size compared with the head width is also useful, mostly for males. Shape of the pronotum, especially width/length proportion, hind angles, microsculpture; colour patterns, though very variable, are also used in the key. Moreover, elytra shape (elongate, subparallel or divergent), pilosity (short, dense and inclined, long, sparse and erect, or both) and colour pattern (entirely black or yellow, dark with lateral and/or sutural stripe pale) are also helpful though sometimes confusing. Finally, the shape of claws (cleft, with a large elongate tooth, a small acute tooth or a large triangular tooth at base) is also very helpful for identification. Green (1940) used mostly the claws on the anterior leg of the males to separate the species because they are more variable, existing in 12 different shapes. It is preferable to use the claws on the posterior leg of both sexes because, though less variable with four different shapes, they can help to identify specimens of both sexes. Females often made up over 80% of the population of a given species.

 

Genus Rhaxonycha Motschulsky

Third tarsomere emarginated, insertion of fourth tarsomere apical. Both claws of all tarsi with an elongate basal tooth, making them appear broadly cleft. Two species are represented in our region.

 

Tribe PODABRINI

Head strongly prognathus, distinctly constricted behind eyes; mandibles simple, falciform; gular suture confluent. Pronotum truncated anteriorly with neck visible from above. Two genera is represented in our region.

 

Genus Dichelotarsus Motschulsky

Pronotum trapezoidal, rectilinear laterally, at least on the anterior half, widest in front of middle. Female tarsal claws broadly toothed at base. More than 17 species are represented in our region.

Genus Podabrus Westwood

Pronotum arcuate laterally, widest at base or near middle. Tarsal claws in both sexes broadly cleft. More than 22 species are represented in our region.

 

Subfamily SILINAE

Tribe SILINI

Lateral pronotal margins often incised or irregularly modified; seventh abdominal sternite deeply invaginated, appearing longitudinally divided. Strong sexual dimorphism, mainly in the pronotum shape. Large and protruding lateral glandular pores on the abdominal tergites; phallobase reduced, most membranous, with two lateral sclerites; lateral lobe large and strongly sclerotized, often fused, in some forming ventral plate; median lobe membranous. Female genitalia with coxites well developed, stylus reduced or absent; proctiger typically more or less triangular, reduced; paraprocts expanded and fused to valvifer; valvifer well developed, fused to paraprocts and coxites. Three genera are represented in our region.

 

Genus Ditemnus LeConte

Head deflexed, mostly concealed from above. Pronotum transverse with lateral margins excavated and modified into an angular process or round tubercles in the postero-lateral region in male, without angular process or tubercles, very transverse, at least 1.6X as wide as long in female. Seventh sternite with a U-shaped invaginated posterior margin, eightth sternite elongate but wide. Two species are represented in our region.

 

Genus Polemius LeConte

Head partly concealed from above; flagellomeres with longitudinal sensory grooves. Lateral margins of pronotum shallowly incised or entire. Seventh sternite with a U-shaped invaginated posterior margin, eightth sternite reduced to a narrow process or apparently absent. Four species are represented in our region.
             

 

Genus Silis Charpentier

Head deflexed, mostly concealed from above. Pronotum transverse with lateral margins excavated and modified into an angular process or round tubercles in the postero-lateral region in male, without angular process or tubercles, very transverse, at least 1.6X as wide as long in female. Seventh sternite with a V-shaped invaginated posterior margin, eightth sternite elongate but wide. Three species are represented in our region.

 

Subfamily MALTHININAE

Small size (1.2–5 mm). Apical maxillary palpomeres radially symmetrical and acutely pointed. Elytra short, abbreviated, exposing numerous abdominal tergites and hind wings often unfolded and covering sternites. Phallobase enlarged, strongly sclerotized, and produced ventrally; internal sac permanently invaginated. Female genitalia with coxites well developed, terminating in a setose enlarged stylus, which is more or less fused with coxites; proctiger typically more or less triangular, reduced; paraprocts emarginated or divided; valvifer well developed and sclerotized.

Tribe MALTHINI

Antennae filiform to slightly subserrate; mandibles with a prominent tooth; frons more or less convex; gular sutures confluent. Caudal abdominal segment of male simple. One genus is represented in our region.

 

Genus Malthinus Latreille

One species is represented in our region.

 

Tribe MALTHODINI

Antennae filiform; frons more or less concave; mandibles simple or finely serrated; gular sutures separated. Caudal abdominal segment of male often modified into an elaborate copulatory apparatus of varied structures and degrees of complexity. One genus is represented in our region.

 

Genus Malthodes Kiesenwetter

More than 14 species are represented in our region.

 

Tribe ICHTHYURINI

Head with terminal maxillary palpomere bilaterally symmetrical. Elytra strongly abbreviated, not concealing hind wings, about 1.5X as long as wide, sutural margin strongly divergent from middle. Caudal abdominal segment strongly modified. One genus is represented in our region.

 

Genus Trypherus Leconte

Two species are represented in our region.

 

Subfamily CHAULIOGNATHINAE

Tribe CHAULIOGNATHINI

Head strongly prognathus; frontoclypeal suture present; mandibles with inner margin unidentate; apical maxillary palpomeres bilaterally symmetrical. Tibial spurs absent. Sternite eight small, asymmetrical, with margins more or less entire; male genitalia distinctly asymmetrical; tegmen produced into two dissimilar elongate processes, of which one is flexible and the other fixed; phallobase strongly sclerotized, and fused to lateral tubercles; median lobe sclerotized. Female genitalia with coxites enlarged, terminating in a setose stylus; proctiger typically more or less triangular, reduced; paraprocts reduced; valvifer fused to paraprocts and coxites. Usually bright aposematic colour species feeding exclusively on pollen and nectar. One genus is represented in our region.

Genus Chauliognathus Hentz

Two species are represented in our region.