Coccinella cassidea Fabricius, 1775

Sekerka, Lukáš & Barclay, Maxwell V. L., 2014, Fabrician types of Cassidinae (Coleoptera: Chrysomelidae) deposited in the Natural History Museum, London, Acta Entomologica Musei Nationalis Pragae 54 (2), pp. 657-684 : 676-678

Coccinella cassidea Fabricius, 1775

( Figs 7–9 )

Coccinella cassidea Fabricius, 1775: 82 .

Cassida cribraria Fabricius, 1775: 90 , syn. nov.

Type locality. Original type locality of C. cassidea : ‘Marylandia’. Due to the designation of neotype a new type locality is established: ‘America’, after the type locality of C. cribraria mentioned by FABRICIUS (1775: 90).

Type material examined. Original type material lost. NEOTYPE (present designation): ♀ (specimen with large spots on the elytra), pinned, ‘ Cassida cribraria | Fab. Entom. p. [p] 90. n. 9. [w, hw, s, bf] || LECTOTYPUS | Cassida | cribraria | Fabricius, 1775 | L. Sekerka & | M.V.L. Barclay des. 2014 [r, p, cb]’ ( BMNH). The specimen is provided with an additional label: ‘NEOTYPE | Coccinella | cassidea | Fabricius, 1775 | L. Sekerka des. 2013 [r, p, cb]’.

Status in ZIMSEN (1964). P. 85; No. 1221 (no material listed).

Original description. ‘C. oblonga rubra:coleoptris punctis duodecim, thorace quatuor nigris. Habitat in Marylandia. Mus. Brit.

Thorax ruber, punctis quatuor nigris, antice emarginatus, margine incrassato, postice tridentatus. Elytra punctis sex, antico minutissimo.’ ( FABRICIUS 1775).

Current status. Chelymorpha cassidea ( Fabricius, 1775) .

Description of neotype. Body elongate oval, 12 mm long ( Fig. 7 ).

Pronotum red with four black spots. Scutellum brownish-black. Elytra red, each elytron with seven spots organized in three rows: ¿rst containing a single postscutellar spot forming a common spot; second row running along approximately internal third width of elytra and containing three spots, one at base, one at the level of postscutellar spot and one slightly behind; third row running along outer third of elytral width and containing three spots, one at humerus, one situated between 2nd and 3rd spot of the second row and one on apicolateral slope. Two internal spots, 2nd and 3rd of the second row, distinctly larger than other ( Figs 7–8 ). Head yellow with black mouthparts, ¿ve basal antennomeres yellow with upper side infuscate, remaining antennomeres black. Thorax including legs black, only episterna of mesothorax slighly paler. Abdomen black, three apical ventrites with a small yellow spot on each side.

Disc of pronotum sparsely but distinctly micro-reticulate and dull. Anterior margin moderately emarginate, swollen. Lateral margins swollen. Basal corners of pronotum strongly projecting posteriorly, thus pronotum distinctly broader than base of elytra.

Scutellum smooth and shiny.

Elytra regularly convex, smooth, without any ribs or elevated structures. Punctation dense, completely irregular. Punctures rather small but distinct, not particularly impressed. Interspaces two to four times wider than puncture diameter. Surface of elytra glabrous.

Clypeus approximately twice as wide as long, coarsely punctate. Prosternal collar moderately projecting towards mouthparts. Prosternal process moderately broad and slightly expanding apically. Tarsal claws divergent with large basal tooth.

Differential diagnosis. Chelymorpha cassidea belongs to a group of species characterized by a red dorsum with distinct black spots, elongate oval body, and weakly convex and ¿nely to moderately punctate elytra. The group contains only three species: C. cassidea ( Fabricius, 1775) , C. phytophagica Crotch, 1873 and C. rugicollis Champion, 1893 . Chelymorpha cassidea differs in bare elytra while C. phytophagica and C. rugicollis have pubescent elytra. The latter also has much coarser punctuation, more numerous spots on the elytra, and the postscutellar spot distinctly elongate. Mesoamerican species of the C. comata Boheman, 1854 group are similarly coloured, but this group differs in densely pubescent and gibbous elytra with coarse punctation, with the exception of C. comata .

Remarks. FABRICIUS (1775) stated that the species was described only from BMNH material. ZIMSEN (1964) was not able to trace any surviving type specimens of this species, and we have also failed to ¿nd any potential type, and thus consider it as lost. Therefore we have designated a neotype.

CROTCH (1873) transferred Coccinella cassidea to Chelymorpha Chevrolat, 1836 and considered C. cribraria as its synonym, but without any additional comments. As the type is lost we can judge only from the original description, and all characters listed apply to the species presently referred to as C. cassidea except Fabricius mentioned each elytron having six spots while the species has usually thirteen spots on elytra (six on each elytron plus one common postscutellar spot). The size of elytral spots is very variable in this species so it could be that Fabricius had some rare colour morph which was missing one of the elytral spots, and counted the postscutellar spot as two, making twelve in total. Regarding elytral punctures Fabricius also stated that the basal punctures are smaller, which is in accordance with most specimens that we have seen. Particularly important characters mentioned by Fabricius are those of the pronotum. He stated that it has thickened anterior and tridentate posterior margin. This is very characteristic of Chelymorpha species , which all have the hind angles of the pronotum projecting backwards, making the basal margin appear tridentate: no such pronotal shape is present in North American Coccinellidae . Fabricius also mentioned the oblong body which would be unusual for most coccinellids of this region. Moreover, Fabricius did not mentioned such characters in other Coccinella species described or treated in the same book ( FABRICIUS 1775), and he must have considered them to be diagnostic for C. cassidea . Therefore we think that the transfer proposed by CROTCH (1873) was correct.

Chelymorpha cassidea is a widespread and very common North American species having several distinct local races, some of which might in the future be revealed as distict species. Moreover, C. cassidea is synonymous with C. cribraria Fabricius, 1775 , which had been used until now for a different species since BOHEMAN (1854). As the two names are published in the same work, we use the First Reviser Principle ( ICZN 1999: Article 24.2.1) to select C. cassidea as the valid name for the taxon because it has been correctly applied, and this avoids changing the generally used name of a common species. In order to avoid any further misapplications of C. cassidea and C. cribraria , we have designated the lectotype of C. cribraria as the neotype of C. cassidea , making the names objective synonyms. Original descriptions of both species agree with the specimen in question.

Figures

Figs 7–12. 7–9 – Cassida cribraria Fabricius, 1775, lectotype, and Coccinella cassidea Fabricius, 1775, neotype; 10–12 – Cassida interrupta Fabricius, 1775, syntype. (7, 10 – habitus dorsal; 8, 11 – habitus lateral; 9, 12 – labels).