Polybia flavifrons Smith, 1857

Amorim, Danielle C. De A., Dos Santos Junior, José N. A., Carvalho- Filho, Fernando Da S., Silveira, Orlando T. & Carpenter, James M., 2024, Taxonomic study of wasp species in the Polybia (Myrapetra) occidentalis group morphologically related to P. scrobalis and P. flavifrons, with description of a new species (Hymenoptera, Vespidae, Polistinae), Zootaxa 5477 (5), pp. 537-562 : 545-546

Polybia flavifrons Smith, 1857

Polybia flavifrons Smith, 1857: 152 . Holotype ♀, Ecuador, Guayaquil (NHM); examined.

Polybia occidentalis var. flavifrons : Bequaert 1944: 286.

Polybia occidentalis flavifrons : Richards 1951: 145.

Polybia flavifrons flavifrons : Richards 1978: 39, 97.

Polybia saussurei Holmgren, 1868: 440 . Lectotype (designated by Richards, 1978) ♀, Ecuador, Puná (NHRS, Stockholm; not found); Synonymy by Richards (1978).

Polybia flavifrons was described by Smith (1857) based on a female collected in Ecuador, Guayaquil, close to the Pacific coast. Polybia saussurei was described by Holmgren (1868), also from a nearby Ecuadorian locality (Puná Island) and was treated as a probable junior synonym of P. flavifrons both by Bequaert (1944) and Richards (1951). Because Holmgren mentioned “California et Puna” as type localities, Richards (1951) thought P. saussurei had been collected in Mexico. After seeing the types in Stockholm and realizing that “Puna” is actually in Ecuador, Richards (1978: 97) designated a lectotype and established the synonymy of P. saussurei under P. flavifrons . Unfortunately, staff of the NHRS recently informed us that they could not find Holmgren’s specimen.

Richards (1978) recognized two other forms as subspecies of P. flavifrons , as follows. Richards (1951), still working under the concept of P. occidentalis as a single species with several intraspecific varieties, treated P. flavifrons as a subspecies of P. occidentalis . However, while redescribing the taxon and listing the examined material (mostly from coastal areas of Ecuador and Peru), he noted considerable variation in number and extension of color marks, with the relatively darker specimens coming from Peru. These Peruvian specimens would form the basis of the subspecies barbatula, only described in Richards’s (1978) book.

Richards (1951) also described a new subspecies' of Polybia parvula (Fabricius) (= P. parvulina Richards, 1970 ; see below), P. parvula hecuba , based on females only from Brazil (holotype from RJ; plus 11 paratypes from PR, RJ, SC, SP). Later, Richards (1978) would recognize this taxon as a subspecies of P. flavifrons , to which he then further added the subspecies barbatula based on females (holotype plus 50 paratypes) from Peru (mentioned above) and Bolivia, and one male paratype from Peru.

From Richards’s descriptions and examination of type material in the NHM (by O. T. Silveira), these three taxa can be diagnosed (see identification key), and this could be seen as sufficient motive to treat them as distinct species, especially P. f. hecuba which has at most very weak traces of a pronotal carina and is darker in color, with the gena totally black, and slightly wider (see below). The other two forms differ in size, degree of development of pronotal carina (it can be clearly distinguished in both; but Richards, 1978: 98, says one barbatula paratype from Huánuco ( Peru) “ has no trace of pronotal keel ”) and vestiture, with P. f. barbatula presenting bristles more evident and in larger extension throughout the body.

According to Richards (1978), the nominotypical subspecies had been found only in Ecuador, in localities near the coast.We examined more recent material of P. f. flavifrons in the NHM from western Ecuador (Manabi, Portoviejo, 22.xii.1971 and Arenillas, 20.ii.1984; M. Cooper). The subspecies P. f. barbatula was reported by Richards (1978) also from western South America ( Peru and Bolivia) but not Ecuador. We found in the NHM a specimen from Ecuador (Loja, Masanamaca, 16.iii.1985, L. Coloma) that agrees with the holotype of P. f. barbatula (from Peru, Lambayeque), showing the yellow marks on the head less reddish, not completely covering the frons, clypeus with a central black area, and with first metasomal segment shorter than in P. f. flavifrons . However, another specimen from coastal Ecuador (Manabi, Tosagua, 6.xii.1985, F. Bravo; NHM) with a shorter first metasomal segment and distinct pronotal carina, has the mesosoma and metasoma (pronotum laterally, entire scutellum, metanotum, and most of propodeum and metasomal tergum 2, plus distal bands on other metasomal segments) extensively marked with orange yellow (more like typical flavifrons ), but the head is mostly black, with just the usual yellow lateral marks on the clypeus and inner orbits. So, although the mentioned differences between typical flavifrons and barbatula, we believe that more material from these forms should be examined before making a decision on their taxonomic status. It is interesting to note that the known distribution of P. f. flavifrons is from coastal areas, while P. f. barbatula has been reported both from places near the coast (Chiclayo, Peru; holotype) as well as from higher inland regions (Cochabamba, Bolivia). So, we here keep the status of barbatula as in Richards (1978).