Diabrotica circulata Harold

Species name

Diabrotica circulata Harold 1875: 91

Type locality

Guatemala

Type depository

MNHN, lectotype, female, verified

Synonyms

nummularis Harold 1877: 110 (type locality: Mexico; type depository: MfN, lectotype, male, verified)

Diagnosis

Body length 6.7-7.3 mm, width 3.4-3.5 mm. Head basic color black. Antennae filiformfiliform:
slender antennae with antennomeres of similar shape
, uniformly yellow. Maxillary palpi yellow or yellow ocher, labrumlabrum:
the "upper lip" of beetles, a movable sclerite joined under clypeus
black or chestnut. Pronotumpronotum:
the notum of the prothorax with highly sclerotized pronotal disc
yellow, mustard yellow, light cadmium or yellow ocher, subquadrate, weakly bifoveate with wide shallow foveae, not shagreened, sometimes with minute wrinkles. Scutellumscutellum:
small, usually triangular shield between the bases of elytra
yellow. Elytra yellow or rufous, with two black bandsbands:
(here) transverse maculae on the beetle elytra
. One yellow macula of the variable size may present in the center of basalbasal:
of or pertaining to the base, as in the first, or basal segment of an appendage; opposite of apical
band on each elytronelytron:
<em>(pl. elytra)</em> the fore highly sclerotized wing of beetle
. Posteriorposterior:
the region of the body parts of the beetle furthest from the head
band may be reduced to oculate or sickle-shaped maculae. Bandsbands:
(here) transverse maculae on the beetle elytra
black, metallic black blue or chestnut. Epipleura completely yellow, sutural anglesutural angle:
the posterior angle or apex of the elytron near the suture
of elytronelytron:
<em>(pl. elytra)</em> the fore highly sclerotized wing of beetle
round, punctation scattered, fine. Abdomen yellow or yellow ocher. Legs yellow or yellow ocher. Aedeagusaedeagus:
the main sclerotized part of the male genitalia; "aedeagus" is used here instead of "median lobe of aedeagus"
symmetric, with five internal sac scleritessclerites:
(here) the sclerotized hooks, spines or plates in the internal sac
.

Known distribution

Mexico, Guatemala, Costa Rica, Panama, Colombia

Host plants

Unknown. Two specimens in the USNM collection were collected on the milkweeds (AsclepiasL.)

Remarks

Smith and Lawrence (1967) designated the lectotype of D. circulata and two paralectotypes (the paralectotype labels with question-marks) in the Allard collection in MNHN. One of the paralectotypes, a male, is morphologically identical with the type. We presume this male to be the male of D. circulata. Genitalia of this male were examined and no any substantial differences were found in internal sac structure between it and the type male of D. nummularis. The currently known range of both species is about the same. Except the very variable macula shape, no any substantial morphological differences occur in both species. Thus, we placed D. nummularis into synonymy of D. circulata.

Potential problems with identification

Diabrotica circulata is very similar to many of the "oculate" species such as D. gratiosa Baly, D. adelpha Harold, D. biannularis Harold, D. bioculata Bowditch and D. godmani Jacoby.
They can be separated by the following features: tibiae of D. gratiosa and D. bioculata are black or darkened by brown, but yellow in D. circulata; pronotumpronotum:
the notum of the prothorax with highly sclerotized pronotal disc
is nonfoveate D. adelpha, but very convex, bifoveate in D. circulata; elytrae of D. adelpha are more convex than in D. circulata; scutellumscutellum:
small, usually triangular shield between the bases of elytra
of D. biannularis is black, but yellow in D. circulata. Diabrotica godmani is smaller in size, its antennae are thinner and longer, slightly moniliformmoniliform:
(here) antennae with bead-like, slightly elongate and swollen antennomeres
, usually bearing the longitudinal costae on the inner margin of antennomeres. Internal sac in D. circulata is very similar to D. pulchella (Jacquelin-du-Val). The internal sac scleritessclerites:
(here) the sclerotized hooks, spines or plates in the internal sac
5B in D. circulata are elongate, handlelike hooks slightly widened and bearing 5-8 big teeth apically, while in D. pulchella they are elongate, handlelike hooks bearing 2-3 big teeth apically. Antennae are yellow in D. circulata, but bicolored in D. pulchella; posteriorposterior:
the region of the body parts of the beetle furthest from the head
maculae on elytra are sickle-shaped or oculate in in D. circulata, but usually round in D. pulchella.