Megatibicen grossa ( Fabricius, 1775 ) Sanborn, 2023

Sanborn, Allen F., 2023, Resolving taxonomic issues of cicadas (Hemiptera: Cicadidae) including new combinations, new synonymies, and revised status, with updates on the diversity of the Brazilian cicada fauna and new records for four South American countries, Zootaxa 5318 (3), pp. 339-362 : 340-341

Megatibicen grossa ( Fabricius, 1775) new combination

[Tettigonia] grossa Fabricius, 1775: 678 (Brasilia).

Cicada auletes Germar, 1834: 65 (Pensylvania (sic )). n. syn.

Fidicina literata Walker, 1850: 91 (Unknown locality). n. syn.

Cicada sonora Walker, 1850: 105 (Unknown locality). n. syn.

REMARKS. Diceroprocta grossa ( Fabricius, 1775) is a species listed in the Brazilian fauna ( Nunes et al. 2023) that has a complex and confused history. Tettigonia grossa was originally reported as being collected in Brazil ( Fabricius 1775). The taxon was then reassigned to three other genera and reported from numerous localities in North and South America before Metcalf (1963a) reassigned the species without comment to Diceroprocta Stål, 1870 where it has remained since ( Duffels & van der Laan 1985; Sanborn 2013). North American records were considered to represent Megatibicen auletes ( Germar, 1834) ( Sanborn & Heath 2017) but the status of the South American records is still in doubt. Since we could not examine the holotype of Tettigonia grossa previously, we were not able to synonymize the species and considered the North American records misapplication of the taxon ( Sanborn & Heath 2017). In addition, the genus Diceroprocta does not extend into South America with the southernmost records being reported (although suspect) from Panama and D. grossa has been considered an incertae sedis species ( Sanborn 2018). The number of incorrectly synonymized species that have occurred historically (see summary in Metcalf 1963a) further illustrate the confusion in how to apply the taxon.

As with most descriptions of the era, the description of Tettigonia grossa is abbreviated. Fabricius (1775) describes the taxon as thorax green, lined with piceous, wings white, bases with posterior yellow spot. Habitat in Brazil. Banks Museum. He then continues with giant in the genus. Rostrum gray-fuscous, with a piceous tip. Frons (could mean postclypeus) transversly sulcate. Thorax dark green, with some piceous lines. Cruciform elevation notched. Fore wings white, veins and costal margin piceous. The inner margin with a piceous base. The hindwings are white, with a large yellow spot at the base.Abdomen fuscus, margins of the segments ciliated, anus pointed. Feet gray, tips piceous. The description is sufficiently vague so that it can be applied to species found in several current genera and tribes and cannot be used alone to distinguish the taxon.

Germar (1834) was equally brief with the description of Cicada auletes . The taxon is described as being olive-colored, white pruinosity on collar. Black lines, black mesothorax, pale lines, hyaline fore wings, fuscous veins, olive-colored costal margin, two externally dark covered anastomoses (radial and radiomedial crossveins). There are additional similarities with Fabricius’ description in the paragraph following the initial description. However, both are sufficiently vague so that the species could not be separated without observing the type specimens.

We are fortunate in that the holotype of Tettigonia grossa survives in the BMNH ( Fig. 1 , type specimen BMNH, Banks Collection, BMNH(E) #668748) and that the holotype of Cicada auletes survives in the ZMD (zoomus. lviv.ua/GERMAR/ZM3845web.htm) so the uncertainty in the status of the taxa can be eliminated. Comparing the images, it is clear that the two specimens represent the same species. As a result, Tettigonia grossa Fabricius, 1775 is reassigned to become Megatibicen grossa ( Fabricius, 1775) n. comb. with Cicada auletes Germar, 1834 n. syn., Fidicina literata Walker, 1850 n. syn., and Cicada sonora Walker, 1850 n. syn. becoming junior synonyms. The synonymies of Walker’s species with Germar’s species was first proposed by Stål (1862). Distant (1906) suggested these synonyms and had access to all holotypes except Cicada auletes . However, the uncertain status of Megatibicen grossa ( Fabricius, 1775) n. comb. and the lack of a discussion as to the reasons for the synonymies meant these synonymies were not widely recognized (see references in Metcalf 1963a). It is also clear ( Fig. 1 ) that the hind coxae lack a large inner protuberance so that Tettigonia grossa cannot be classified in the genus Diceroprocta or the Fidicinini Distant, 1905e ( Marshall et al. 2018).

Making Cicada auletes n. syn. a junior synonym of Megatibicen grossa n. comb. is done here because Article 23.9.1.1 of the Code (ICZN 1999) cannot be applied even though Article 23.9.1.2 is met. As a result, Article 23.9.2 cannot be used to grant precedence to Germar’s name as a nomen protectum and the synonymy must occur. This case is similar in many ways to that of another common North American species, Neotibicen tibicen ( Linnaeus, 1758) ( Sanborn 2008a) . Although there was some resistance when the change to Linnaeus’ species was published, people have adapted and have used the correct name since that time. Under Article 23.9.3, a petition to the Commission would be necessary to suppress Megatibicen grossa in favor of Megatibicen auletes under Article 81 (plenary powers) since Article 23.9.1.1 is not met.

The labels associated with the holotype of Tettigonia grossa clearly state Brazil as the collection location ( Fig. 1 ). However, this is an obvious case of an incorrect label being associated with a specimen that was probably collected on an extended expedition and the incorrect label being added during the curation process at a later date. A similar example from the same time period is Quesada gigas ( Olivier, 1790) being reported to originate in Java when the species is found over most of the New World ( Sanborn & Phillips 2013). The range of Megatibicen auletes covers most of the eastern half of the United States of America (including 31 states) ( Sanborn & Phillips 2013). As a result, the type locality given in Fabricius (1775) is considered to be a mistake and Megatibicen grossa is not part of the Brazilian cicada fauna.

DISTRIBUTION. The species has been reported from most of the eastern half of the United States of America ( Metcalf 1963a; Duffels & van der Laan 1986; Sanborn 2013; Sanborn & Phillips 2013).

Figures

FIGURE 1. Tettigonia grossa Fabricius, 1775 type specimen (BMNH(E)#668748) dorsal (left) and ventral (right) habitus. ©The Trustees of the Natural History Museum, London.