New records of the Neotropical genus Phaonantho Albuquerque (Diptera: Anthomyiidae)

. The genus Phaonantho Albuquerque (Anthomyiidae) comprises three species: P. mallochi (Curran), P. benevola Couri, and P. sordilloae Pamplona & Couri. These species are distributed in the neotropics. In this study, we updated the distributional knowledge for Phaonantho species, including the first record of the genus in Bolivia, Paraguay, Peru, and Mexico, and additional new records to Brazil.


INTRODUCTION
Phaonantho Albuquerque is a neotropical genus comprising three species (Pamplona & Couri, 1993), distributed from Central America to southern Brazil.This distribution pattern is exceptional compared to most genera of anthomyiids, which are scarce or absent in warm lowland forests (Michelsen, 1996).Albuquerque (1957) previously classified Phaonantho as Muscidae, with anthomyiid flies considered a subfamily of Muscidae; the author indicated that the genus was an intermediary form between Phaoniinae and Anthomyiinae, both members of the Muscidae at that time.Cilia on the ventral apex of the scutellum, interfrontal setae on females, three anterodorsal setae on hind tibia, and general appearance resembling Anthomyiidae are present in this genus.However, characters such as lower calypters longer than upper ones, a short vein A₁ (not reaching the wing margin), and a posterodorsal calcar on hind tibia resembling Phaoniinae flies (Muscidae) are also present.
Phaonantho is monophyletic based on three synapomorphies: two proclinate orbital setae on females, two median setulae on pregonite, and epiphallus absent.Additionally, Phaonantho exhibits six homoplasies: one reclinate orbital seta on females, a narrow prosternum, lower calypter longer than the upper one, cerci distally with a quadrangular margin, two long distal setulae on pregonite, and pregonite length equal to that of the postgonite (Gomes & de Carvalho, 2023).
With the present study, we significantly contribute to the understanding of Phaonantho species' distribution pattern.In addition, we present an updated identification key and discuss the collection methods and the distribution pattern of this genus.

MATERIAL AND METHODS
The studied material is deposited in the following institutions: Centro de Coleções Taxonômicas, Museum, Washington D.C., United States of America (USNM).
Diagnosis: Male holoptic (Figs.1A, 2A, 3A) and female dichoptic (Figs. 1D,2D,3D).Male frons at the narrowest point with contiguous fronto-orbital plates (Figs. 1A,2A,3A).Two pairs of frontal setae.Gena, proboscis, and antennae are light to dark brown.Arista plumose.Palpi filiform.Females with a pair of interfrontal setae, two pairs of proclinate orbital setae (the upper one being very short), and one pair of reclinate orbital setae (Figs. 1D,2D,3D).One to two anterior anepisternal setae.The prealar seta shorter than the posterior notopleural seta.The apex of the scutellum is setulose ventrally.Prosternum bare.Dorsocentral setae 2+3.Katepisternal setae 1+2, lower and upper katepisternal setae, similar in length in males.Wings hyaline or brownish without spots.Veins bare, except for the presence of microtrichia, also present on the wing membrane.Vein A₁ short, not reaching the wing margin (Figs.1C, F).Lower calypter twice as long as the upper calypter.Male fore tibia with a median seta on the posteroventral surface.Female fore tibia with a median seta on the anterodorsal and posteroventral surfaces.Hind tibia with a submedian anteroventral seta, three anterodorsal setae, and a median posterodorsal seta (calcar) twice the tibial width.Fore and hind basitarsi, with a conspicuous ventrobasal seta.Abdomen light brown, basally yellowish.Tergites with marginal setae developed, the laterals longer.Sternite one setulose.Male terminalia: surstyli bifurcated, shorter than cerci; cerci wide and rounded, length equal to that of the epandrium width in lateral view; pregonite covered by long setae.

Distribution
We have updated the distributional knowledge of the genus, including the first record of Phaonantho in Bolivia, Paraguay, Peru, and Mexico, as well as the first records across Brazilian states: Amazonas, Bahia, Goiás, Maranhão, Pará, Paraíba, Paraná, Piauí, Rio Grande do Sul, Rondônia, Roraima, and Santa Catarina (Fig. 4).Phaonantho benevola and P. sordilloae are mainly distributed in the Boreal Brazilian, Paraná, Chacoan, South Brazilian, and South-eastern Amazonian dominions (sensu Morrone, 2014), with both species co-occuring in most regions where they have been recorded.In contrast, P. mallochi is mainly distributed in the Paraná dominion, with only a few known records in the Boreal Brazilian, Chacoan, and Pacific dominions (Fig. 4).Remarkably, P. mallochi is distributed in Panamá and Guyana (Curran, 1934).Conversely, the remaining records are exclusively from southern, southeastern, and northeastern Brazil and Paraguay, with no presence in Bolivia, Peru, and Northern Brazil, where P. benevola and P. sordilloae have numerous records.Our study introduces numerous new records for Phaonantho species, but the distribution of these species probably are even wider.

DISCUSSION
We have examined a significant number of specimens representing the three recognized species of Phaonantho.Through our observations, we noted that some characters indicated by Pamplona & Couri (1993) key are intraspecific variation.These morphological variations are as follows: the number of posterior anepisternal setae ranged between 3 and 5 in P. benevola and P. sordilloae; the number of anterior anepisternal setae ranged between 1 and 2 across all three species; and hind femur exhibited a range of 2 to 4 anterodorsal and anteroventral setae also in the three species.Therefore, we updated the Phaonantho key by omitting these characters and including the new information presented in the key above.Some studies have indicated that P. mallochi is an asynanthropic species in Campinas (Linhares, 1981), São Carlos (Oliveira, 1986), and Rio de Janeiro (D 'Almeida, 1992).Linhares (1981) collected P. mallochi from human feces and mouse carcasses as bait.Based on label information of the numerous specimens of Phaonantho that we examined, these specimens were primarily collected using Malaise, light, and Shannon traps with various baits including fish, bovine lungs, feces, and pig carcasses.In addition, P. mallochi was collected from Aristolochia giberti Hook (Aristolochiaceae), a genus known for its pollination by various families of flies (Endress, 1994).
Gomes & de Carvalho ( 2023) recovered the topology of P. mallochi (P.benevola + P. sordilloae).This topology agrees with the distribution of these species, considering that P. benevola and P. sordilloae co-occur mainly in the northern portion of South America, whereas P. mallochi occurs mainly in southeastern South America.
The distribution pattern of Anthomyiidae is mainly concentrated in cold areas at high altitudes or latitudes (Michelsen, 2010).Nevertheless, Phaonantho species (as well as Coenosopsia) are an exception, occurring mainly in the warm lowland forests of Central and South America (Michelsen, 1996).This concurs with our current understanding of Phaonantho distribution pattern.Phaonantho mallochi had a wider longitudinal distribution pattern among the three species, reaching colder southern regions.