Pherbina cayennensis, Robineau-Desvoidy, 1830: 689

Murphy, William L., Abercrombie, Jay, González, Christian R. & Knutson, Lloyd, 2023, Overview of the Sciomyzidae (Diptera: Sciomyzoidea) of the Americas south of the United States, Zootaxa 5345 (1), pp. 1-113 : 59

cayennensis Robineau-Desvoidy, 1830: 689 (Pherbina) ; nomen dubium

HT:? [ French Guiana] “Cayenne.” MNHN. Lost (in litt. Christophe Daugeron, MNHN, 12. November 2014 to WLM) [ Murphy et al. 2021: 159]

Note 1: Steyskal 1974: 429 remarked:

“Another name that may possibly be referred to Dictyodes is Pherbina cayennensis Robineau-Desvoidy (1830: 689) , the entire description of which is as follows:

‘4. Pherbina cayennensis R. D. Simillima Ph. reticulatae ; magis flava; alae rete maculisque magis bruneis. Cette espèce, tout-à-fait semblable au Ph. reticulata d’Europe , a l’ensemble du corps plus fauve; les taches et le réseau des ailes sont d’un brun plus prononcé. Cette espèce, originaire de Cayenne, fait partie de la collection du comte Dejean.’ [Translation by WLM of the French portion of the description: ‘This species, quite like Ph. reticulata of Europe, has the entire body more tawny; the spots and the network of the wings are of a more pronounced brown. This species, originally from Cayenne, is part of the collection of Count Dejean.’]

“Efforts to locate the type have been fruitless, and it must be presumed lost. Comparison of the species by its author with the European Pherbina reticulata [= P. coryleti ( Scopoli, 1763) ] is all that permits reference of the species to Dictyodes . Nothing resembling P. coryleti has been recovered from northern South America (Cayenne = French Guiana), and until such a specimen may be found and treated as a neotype the name Pherbina cayennensis must be considered a nomen dubium.”

Note 2: Murphy et al. 2021: 159 noted that under “Unplaced species” in A Catalogue of the Diptera of the Americas South of the United States, Knutson et al. (1976: 64.13) listed “ cayennensis Robineau-Desvoidy,1830:689 (Pherbina) .Type-locality: French Guiana, Cayenne [?,lost].” Christophe Daugeron (in litt. 12 November 2014 to WLM), while preparing an inventory of type specimens of Diptera in the MNHN, confirmed that the type is indeed lost: “ ... we recently inventoried the Robineau Desvoidy collection and there are no sciomyzids.” Thus, as per Steyskal (1974), the name cayennensis must be considered a nomen dubium, which Article 75.5 of the ICZN restricts to “a nominal species-group taxon [that] cannot be determined from its existing name-bearing type.” A specimen of D. dictyodes from Rio de Janeiro represents the closest collection site to French Guiana of a species of Dictyodes . However, Robineau-Desvoidy’s brief description of P. cayennensis also fits the general aspect of the two species of Guatemalia that are known from Guatemala and Honduras. The only records of any Sciomyzidae from French Guiana are Sepedonea annulata , S. guianica , the recently described Thecomyia diederiki , and T. longicornis .