Ceratophya carinifacies (Curran, 1934)

Reemer, Menno, 2013, Taxonomic exploration of Neotropical Microdontinae (Diptera: Syrphidae) mimicking stingless bees, Zootaxa 3697 (1), pp. 1-88 : 17-19

Ceratophya carinifacies (Curran, 1934)

Figs 29–35 .

Microdon carinifacies Curran, 1934: 376 .

Studied type specimens. HOLOTYPE. Female. GUYANA. Label 1 (red): " Microdon carinifacies Curran Type "; label 2: "Trop. research station New York Zool. Society, No. 201330"; coll. AMNH. The specimen is in bad condition: ventral parts of the thorax are missing, as well as front legs and all tarsi, and the wings are badly damaged. Attached to the pin is also an empty puparium, from which the female holotype has apparently been reared.

Additionally studied specimens. BRAZIL: 1 female, RO Fazenda, Rancho Grande, 62 km s. Ariquemes, 10°18’S 62°53’W, 8–20.IV.1997, malaise trap, leg. A.C. Rhen & C. Alexander, coll. UCD.

Redescription (based on holotype)

Adult female. Body size: 8 mm.

Head. Face occupying 2/5 of head width in frontal view; parallel-sided; submedially depressed; pale yellow, with brown median vitta from antennal fossa to oral margin, where it is at its narrowest; entirely short, appressed yellow pilose. Face in profile straight, produced downward at anterior oral margin. Gena blackish. Frons brown, short pale pilose; vertex blackish brown, short white pilose. Occiput blackish. Eye bare. Antennal fossa about as wide as high. Antenna with scape basally yellow, gradually getting brown in apical 1/2; pedicel and basoflagellomere blackish brown; antennal ratio approximately 4:1:5.5. Basoflagellomere parallel-sided, with apex directed a little upward. Arista slender, about half the length of the basoflagellomere.

Thorax. Scutum blackish brown, except narrowly yellow along margins; short black pilose, except lateral fasciae of white pile along anterior margin and transverse suture, and a complete white pilose fascia between postalar calli. Postpronotum and postalar callus yellow; short yellow pilose. Scutellum yellow, short yellow pilose; semicircular, without sulcus or calcars. Anterior and posterior part of anepisternum not differentiated; short yellow pilose except on ventral 1/3. Anepimeron entirely white pilose. Katepisternum white pilose, at least dorsally (ventral part not visible in type specimen). Katatergum and anatergum microtrichose. Other pleurae bare. Calypter and halter yellow.

Wing: hyaline; microtrichose, except bare on costal cells, basal 1/2 of cell r1, basal 1/3 of cell r4+5, entirely on cell r-m except for traces of microtrichia around vena spuria , on cell bm, on basal 1/4 of cells DM and CuA1, on anterobasal 1/2 of cell cup.

Legs: Front legs and all tarsi missing in holotype. Mid- and hindfemora and -tibiae yellowish brown, midfemora paler on apical half. Legs short and appressed pilose, black on femora, yellow on tibiae. Coxae and trochanters brownish, with pale pile.

Abdomen. Tergite 1 brownish. Tergite 2 brownish with large, oblique, lateral yellow markings over entire length, which leave narrow brown lateral margins and a large median brown triangle. Tergite 3 brownish with yellow lateral margins and a widely yellow posterior margin, which vaguely extends forward medially and gradually turns into pale brown. Tergite 4 mostly yellow, except brownish sublaterally. Tergite 5 yellowish brown. In profile with tergite 4 almost perpendicular to tergite 2, so apex of abdomen curved downward. Tergites short pilose, mostly black on brown parts and yellow on yellow parts. Sternites yellowish brown, short pale pilose.

Male. Unknown.

Puparium. Figs 34–35 . Length about 8 mm., dorsally more or less flat, ventrally convex. Head skeleton and anterior parts (including anterior spiracles) lost. Posterior spiracle not visible.

Diagnosis. Recognizable by the yellow posteromedian part of tergite 2 in combination with the unsulcate scutellum.

Notes. The female from Brazil is darker in overall colouration: the scutellum has two blackish marks posteroventrally, tergites 3 and 4 are black with yellow posterior margins (tergite 3 also with yellow lateral margins).

Distribution. Known from Brazil and Guyana.

Ceratophya longicornis Wiedemann, 1824 (excluded from Ceratophya )

Ceratophya longicornis Wiedemann, 1824: 14 . Type locality: Brazil. [type lost]

English translation of German description in Wiedemann (1830): "Antennae black, basally brown; third segment four times longer than first; face fawn-coloured ['rehhaarbräunlich']; frons black. Scutum black, with traces of fawn-coloured hairs along anterior margin, transverse suture, posterior margin and lateral margins. Abdomen black, second segment longer than in preceding species [ C. notata ], a little narrower than the other [segments], with 'longish', posteriorly forked ['hinten kurz gabelförmigen oder zweispitzigen'] yellow marking which does not reach the posterior margin. Base of abdomen ventrally and sternal margins widely yellow. Wing yellowish. Femora black, with narrowly yellow apex; tibiae and tarsi yellow.—In my collection, a specimen treated with arsenic-solution, because of which the colours are not well discernable."

Notes. According to Wiedemann (1830) the type was in his personal collection, which usually means that it is conserved in the NMW collection. However, no specimen recognizable as the type of C. longicornis is present in the NMW (pers. comm. P. Sehnal). It is not in the ZMHB collection either (pers. comm. J. Ziegler). Wiedemann (1830) wrote that the specimen had been treated with arsenic, a common practice in those days to prevent insect depredation of entomological collections. Sometimes arsenic solutions were applied in a mixture with other ingredients, e.g. soap or mercury (Albrecht 1993). Perhaps the chemical treatment of the specimen has eventually led to its disappearence.

The original description provides some indications that C. longicornis is quite different from other Ceratophya species:

basoflagellomere four times longer than scape (in all other Ceratophya species the basoflagellomere is less than twice as long as the scape);

the second tergite is longer than in C. notata and narrower than the other tergites (suggesting a constricted abdomen, which is found in no other Ceratophya species).

These characters indicate that C. longicornis is probably not a true Ceratophya as defined by Cheng and Thompson (2008) and Reemer and Ståhls (2013a). At present the taxonomic affinities of C. longicornis remain unclear. However, there are few Neotropical species of Microdontinae with such an antennal ratio combined with a constricted abdomen, so possibly the identity of C. longicornis can be clarified later.

Figures

FIGURES 22 – 31. 22. Carreramyia tigrina (holotype), scutellum. 23. Carreramyia megacephalus male (Costa Rica, coll. RMNH), genitalia lateral. 24 – 28. Ceratophya argentinensis female (holotype). 24. habitus dorsal; 25. habitus lateral; 26. head frontal; 27. head lateral; 28. wing. 29 – 31. Ceratophya carinifacies female (holotype). 29. habitus dorsal; 30. abdomen dorsal; 31. abdomen lateral.

FIGURES 32 – 41. 32 – 35. Ceratophya carinifacies female (holotype). 32. head frontal; 33. head lateral; 34. puparium lateral; 35. puparium dorsal. 36 – 41. Ceratophya notata male (holotype). 36. habitus dorsal; 37. habitus lateral; 38. head frontal; 39. head lateral; 40. wing; 41. scutellum.