Charissa Curtis, 1826

Erlacher, Sven, Palma, Laura Marrero & Erlacher, Josepha, 2017, A systematic revision of Charissa, subgenus Pterygnophos Wehrli, 1951, with description of a new species (Lepidoptera: Geometridae), Zootaxa 4341 (3) : -

Charissa Curtis, 1826 nomen protectum

(= Hyposcotis Hübner, [1825] nomen oblitum)

Charissa Curtis, 1826 , British entomology; being illustrations and descriptions of the genera of insects found in Great Britain and Ireland. John Curtis, London: object number 105.—Type species: Geometra obscurata [Denis & Schiffermüller], 1775, originally designated as “ Geometra obscuraria Hüb. ” (unjustified emendation).

Hyposcotis Hübner, [1825], Verzeichniss bekannter Schmettlinge [sic!], Jakob Hübner, Augsburg: 314.—Type species: Geometra mucidaria Hübner , [1799], by subsequent designation by Prout (1904: 122).

Diagnosis. The genus Charissa is characterized by the following autapomorphic character states:

– Juxta divided into two arms, without terminal spines

– Costa more sclerotized than the rest of the valva, pilose but with not more than one or two spines – Ductus bursae (= part between antrum and base of ductus seminalis) not present or extremely short – Bursa copulatrix with sclerotized longitudinal folds

Moths belonging to Charissa are externally very similar to those belonging to Gnophos , Gnophopsodos Wehrli, 1945 , Rhiphignophos Wehrli, 1951 and several other genera, which are just as perfectly adapted to rocks. Most of the species of Charissa are medium sized moths with medial lines and discal spots often distinct. The antennae of males range from filiform to not more than shortly bipectinate, both states occurring even in the same subgenus (e.g. Cnestrognophos Wehrli, 1951 ). Hind tibiae are clavately thickened. The wing venation is very variable in the genus, even within a single species, and not at all constant as indicated in Sauter (1990).

Unlike the situation with external characters, the species of Charissa can be recognized by their male and female genitalia (see list of autapomorphies).

Distribution. The genus Charissa currently comprises about 70 species occurring across the Palearctic ecozone and the Arabian Peninsula. One member of the subgenus Dysgnophos Wehrli, 1951 also occurs in the Nearctic.

Remarks. Objectively, there are some problems in using the name “ Charissa ”. In his bibliographical account of the entomological works of Jacob Hübner, Hemming (1937) concluded that the pages 305–431 of Hübner’s “Verzeichniss bekannter Schmettlinge [sic!] ” including the generic name Hyposcotis most likely appeared in 1825. On this basis, he initiated an “Opinion” by the International Commission on Zoological Nomenclature to establish his findings in order to stabilize nomenclature (ICZN 1943). When Sauter (1990) proposed the genus name Charissa Curtis, 1826 for several subgenera and species formerly belonging to Gnophos Treitschke, 1825 , he obviously overlooked that Hyposcotis Hübner, [1825] should have been used, although Fletcher (1979) already considered both Hyposcotis and Charissa as valid. However, since their type species, Geometra mucidaria Hübner , [1799] and Geometra obscurata [Denis & Schiffermüller], 1775 respectively, are currently treated as congeneric (e.g. Parsons et al. 1999), Charissa and Hyposcotis must be considered to be synonyms. For Hyposcotis, to our knowledge, there are only four sources in which it has been used according to Article 23.9.1.1. ICZN after 1899 ( Prout 1904, Oberthür 1913, Prout 1912 –1916, Prout 1914). Apart from the general list in Fletcher (1979) (according to Article 23.9.6. ICZN), more than 100 years have passed without Hyposcotis being used as a genus name. On the other hand, many authors have increasingly used Charissa in their publications since Sauter (1990) and now the name is widely adopted, as exemplified in Erlacher & Erlacher (2017). Nevertheless, the name Hyposcotis instead of Charissa was recently used by two Turkish colleagues (e.g. Kemal & Koçak 2015; Kemal & Koçak 2016). Even if this seems unnecessary, it is in accordance with a strict interpretation of the ICZN (2017). To avoid taxonomic instability and confusion amongst the scientific community it was decided to refer this matter to the International Commission of Zoological Nomenclature for a ruling under the plenary power ( Erlacher & Erlacher 2017). According to § 23.9.3. ICZN the prevailing usage of Charissa Curtis, 1826 is to be maintained while the case is under consideration (nomen protectum).