Dicaelus (Paradicaelus) elongatus Bonelli 1813

Dicaelus (Paradicaelus) elongatus Bonelli
Dicaelus elongatus Bonelli, 1813:448.
Dicaelus simplex Dejean, 1826:389; [type specimen in Oberthiir Coll. (fide
Lindroth).] Type locality: " Amerique septentrionale " ; (the specimen
was sent to Dejean by Le Conte, and was presumably collected either in
New Jersey or Georgia).— Le Conte, 1848 : 430.— Ibid., 1853 : 389.— Horn,
1880 : 52.— Casey, 1920 : 406. Dicaelus ambiguus Le Conte not Laferte, 1841, 1848:428; [a single specimen
in the Le Conte collection bearing the label " var. ambiguus ? Ferte Ala."
is a member of D. elongatus Bon., and is presumably the specimen on
which this record was based]. — Ibid., 1853:389. Dicaelus opacus Le Conte not Laferte, 1841, 1848:429; [one specimen from
Alabama, collected by Haldeman]. — Horn, 1880:52. Dicaelus obscurus Le Conte, 1848:428; [type specimen a female, in the Le
Conte Coll., MCZ no. 5716]. Type locality: "southern states"; (type
specimen labelled with an orange disc). — Ibid., 1853:389. Dicaelus debiliceps Casey, Mem. Col., Vol. Ill, p. 151, 1913; New synonymy;
[type specimen a female, in Casey Coll.]. Type locality: Buena Vista
Spring, Franklin Co., Pa.— Ibid., 1920:206. Dicaelus ashevillensis Casey, ibid.; New synonymy; [type specimen a male, in
Casey Coll.]. Type locality: Asheville, North Carolina; (determined from
original description). Specimens of this species which lack the extra pair of setae on the pronotum are liable to be confused with members of the typical subspecies of Dicaelus jurvus. However, the two are readily differentiated on the mandibular characters, D. elongatus having a well developed terebral tooth on the left mandible and lacking a dorsal protuberance, and D. jurvus lacking the terebral tooth on the left mandible but having a small protuberance on the dorsal surface close to the terebral margin (figs. 83a and 86a). Beyond its superficial similarity to D. j. jurvus, D. elongatus is a very distinctive species within the genus Dicaelus.
Variation. — For the number of synonyms listed under this species, variation is, at most, slight and local or individual. Size variation for a series of twenty males and twenty females, chosen at random from localities scattered throughout the range of the species, is as follows : males, length 15.2-19.0 mm. (16.6 mm. ), width 6.0-7.8 mm. (6.7 mm.); females, length 14.9-18.4 mm. (16.4 mm.), width 6.0-7.7 mm., (6.6 mm.). Variation in size seems to be clinal in nature, with specimens from the Gulf Coastal states averaging distinctly larger than specimens from farther north and specimens from peninsular Florida (see Ball, 1954: 313 and table 25 for details). The proportions of the terminal segments of the palpi vary slightly.
The pronotum (fig. 91) is either more or less strongly constricted posteriorly and the sides are, in a few specimens, more or less reflexed laterally. The number of setigerous punctures on each side of the pronotum varies from two to as many as four, with a distinct mode at two. Data on variation in this character are presented in table 20. Because the two sides of a single pronotum frequently do not have the same number of punctures, the sum total is used rather than the number of punctures on a single side. The surface of the pronotum varies from almost smooth to rugulose, the smoother specimens occurring generally in the northern part of the species range and the more rugose ones farther south. The disc is somewhat flatter than average in specimens from Hope, Arkansas.
The setigerous punctures on the 6th abdominal sternite vary in number from 4-6 (4.8) in the males, and from 6 to 8 (6.8) in the females.
The median lobe of the male genitalia is as in figs. 107a and b, but the apical portion exhibits considerable variation in shape, as follows :
left margin straight rather than concave, right margin strongly obtuse, the apex, therefore, broadly truncate and appearing shorter than in fig. 107b; as in fig. 107b, but apex more rounded; apex as in figure, but more strongly inclined toward left; apex less inclined to left (twenty specimens have been examined).
Synonymical Notes. — The synonymy of this species as presented in the Leng Catalogue is satisfactory, except that simplex and debiliceps should be reduced to synonyms of Dicaelus elongatus. Both are founded on characteristics such as size and slight differences in proportions which are neither great enough nor constant enough to have taxonomic value. I have examined a large series of specimens from Asheville, North Carolina, the type locality of D. ashevillensis Casey, and find that the characters associated with this name are features of only an individual, and not of the entire Asheville series. Various specimens from this one locality can be placed in typical elongatus, typical ashevillensis, or neither, depending upon whether the pronotum narrows anteriorly from before or behind the middle, this being the key character which separates these species. A second variable feature, less unequally elevated intervals of the elytra as opposed to more unequally elevated intervals as in D. elongatus and simplex, seems to vary at random and not in a geographical pattern. Therefore, D. ashevillensis should also be treated as a synonym of D. elongatus.
Immature Stages. — See Schaupp ( 1878 : 43 and 44) for description of larva and pupa of this species, and data on life history.
Distribution. — This species ranges from southern Quebec to southern Florida in the east, to at least 4000' elevation in the Smoky Mountains, westward into the Plains, northward to northern Iowa, westward probably no farther than the 100th Meridian, and southward to northeastern Texas. I have collected this species on dry hillsides in October in the vicinity of Ithaca, New York, and have found it in moist leaf litter in a swamp in the vicinity of Oneco, Manatee County, Florida.
Two hundred forty-seven males and two hundred eighty-six females collected in the following states and provinces have been examined.
Peripheral localities — New Hampshire: Sullivan County, Cornish. New York : King's County, Staten Island. Florida : Dade County, Paradise Key. Kansas: Douglas County, Lawrence. Michigan: Oakland County, Milford. Additional states — Alabama. Arkansas. Connecticut. District of Columbia. Georgia. Illinois. Indiana. Iowa. Kentucky. Louisiana. Maryland. Massachusetts. Mississippi. Missouri. Nebraska. New Jersey. North Carolina. Ohio. Oklahoma. Pennsylvania. Rhode Island. South Carolina. Tennessee. Texas.

Dicaelus elongatus is a species of ground beetle in the family Carabidae. It is found in North America.