Cis pallidus Mellié, 1849: redescription, new synonym, geographic distribution, and host fungi records

Abstract Cis pallidus Mellié, 1849 is redescribed based on specimens from Northeast, Southeast, and South Brazil, and from Argentina. A lectotype is designated for Cis semipallidus Pic, 1916, and the species is synonymized with C. pallidus. The first host fungi records and a distribution map for the species are provided.


Introduction
Cis Latreille is the most diverse genus of Ciidae with approximately 400 described species and a worldwide distribution (Oliveira et al. 2013, Lawrence 2016. The genus contains more than half of all described Ciidae species (Lawrence 1971, Oliveira et al. 2013, Lawrence 2016. The Neotropical species of Cis (biogeographic regions sensu Morrone 2015) are represented by nearly 70 described species and at least half of them are organized into artificial species-groups, such as the comptus, creberrimus, melliei, pallidus, taurus, tricornis, and vitulus species-groups.
The pallidus-group comprises C. corticinus Gorham, 1883 from Totonicapán, Guatemala, C. pallidus Mellié, 1849 from the state of Bahia, Northeast Brazil, C. semipallidus Pic, 1916 from Buenos Aires, Argentina, and C. tetracentrum Gorham, 1886, which occurs from southern California and Arizona to southern Mexico (Mellié 1849, Lawrence 1971, Gorham 1883, 1886. These four species share an elongate body with single and uniform elytral punctation, dorsal vestiture of short to long bristles, slightly tumid prosternum, and males with a very small sex patch on the first abdominal ventrite or none at all (Lawrence 1971;pers. obs.). These species are morphologically closely related to species in the vitulus-group, which are similar but usually have a comparatively less elongate body (Lawrence 1971;pers. obs.).
The aim of this paper is to redescribe C. pallidus, propose a new synonym, and provide new host fungi and geographic distribution records.

Materials and methods
The examined specimens are listed in the section on "type material" and "additional material" below. A total of 12 males from eight localities were dissected, as follows (number of specimens between parentheses): Buenos Aires (1; lectotype of Cis semipallidus) and Famaillá (1), in Argentina; Rio de Janeiro (1), São João del-Rei (1), Viçosa (5), Palotina (1), Nova Teutônia (1) and Urubici (1) Terms for external morphology and male terminalia of ciids follow Lopes-Andrade and Lawrence (2005, Lawrence et al. (2011), andLawrence (2016), but see also Oliveira et al. (2013) for an explanation on the use of "tegmen". The following abbreviations are used for measurements (in mm) and ratios: BW (basal width of scutellar shield), CL (length of antennal club measured from base of the eighth to apex of the tenth antennomere), EL (elytral length along the midline), EW (greatest width of both elytra), FL (length of antennal funicle measured from base of the third to apex of the seventh antennomere), GD (greatest depth of body measured in lateral view), GW (greatest diameter of eye), PL (pronotal length along midline), PW (greatest pronotal width), SL (length of scutellar shield), TL (total length counted as EL+PL, i.e. excluding head).
The GD/EW and TL/EW ratios indicate the degree of body convexity and elongation, respectively.
A total of 21 males and 20 females were measured, with representative specimens from all examined localities. Measurements of antennomeres, GW, and BW provided in the description are the mean measurements of three males from three localities (Viçosa, Atílio Vivacqua, and Nova Teutônia); in these cases, standard deviations are not provided because they were 0.01 or less.
For scanning electron microscopy (SEM), specimens were dehydrated in a series of alcohol and acetone solutions, critical point dried (CPD 020, Balzers, Liechtenstein), mounted on aluminum stubs and sputter coated with gold (sputter module SCA 010, Balzers). Samples were then examined under a SEM (LEO VP 1430, Zeiss). Transcription of labels, dissection, photography under optical equipment, and measurement of specimens followed the methods provided by Araujo and Lopes-Andrade (2016). Names of host fungi extracted from labels were updated consulting the online database of Index Fungorum (http://www.indexfungorum.org) and are summarized in the section "Host fungi". The criteria provided in Orledge and Reynolds (2005) are followed for determining breeding records. The distribution map ( Fig. 45) was generated using the on-line SimpleMappr tool (Shorthouse 2010).

Taxonomy
Variation in pronotal and elytral color occurred between specimens from the same locality or even from the same basidiome. Also noticeable was variation in the length of dorsal bristles, mainly those on the pronotum (compare Figs 1,9,12,[15][16][17][18][19][20][21]. The comparatively darker elytra and longer pronotal bristles of specimens of the type series of C. semipallidus were observed in several named specimens of C. pallidus. There was little variation in size and morphology of tegmen and penis between dissected specimens from eight localities (30)(31)(32)(33)(34)(35)(36)(37)(38)(39)(40)(41)(42)(43)(44). Length of tegmen varied from 0.29 to 0.36 mm, and of penis from 0.26 to 0.33 mm. The very rounded apical lobes of tegmen observed in two cases (Figs 6, 32) were artifacts of preparation, and occurred when the tegmen was dorso-ventrally-flattened between slide and cover slip. To confirm this, we photographed a tegmen before (Fig. 40) and after distortion (Fig. 41). No conspicuous sex patch was observed externally on the first abdominal ventrite of males, neither under stereomicroscopy nor under SEM (Figs 22, 28), but a possibly vestigial small mark was observed in all dissected males (e.g. Fig. 29, arrow). No diagnostic features to sustain C. semipallidus as a separate species have been found; thus we propose it as a junior synonym of C. pallidus.

Diagnosis.
Distinguished from other South American ciids by the elongate body (TL/ EW at least 2), reddish to dark brown head and pronotum, yellowish elytra with a black band on both sides, and pronotum projected forward, partially or completely covering head when seen from above. Among South American ciid species with lightcolored elytra, Orthocis platensis Brèthes, 1922 differs in the pronotum being not projected over the head. Cis bisbidens Gorham, 1883 differs in lacking lateral elytral band, in the developed projections associated with the male head and pronotum, and the small but conspicuous sex patch on first abdominal ventrite of the male. Cis granarius Mellié, 1849 has a comparatively stouter body and the sides of pronotum are lightcolored. In C. grossus Mellié, 1849 andC. validithorax Pic, 1916 only the apical portion of the elytra is light-colored. Cis steinheili Reitter, 1878 is devoid of conspicuous lateral dark longitudinal band on elytra and the male has an obvious sex patch on the first abdominal ventrite.
Females. Projections of head and pronotum more rounded and less prominent than in males. Otherwise like males, but first abdominal ventrite devoid of any discernible mark. Female abdominal terminalia (in specimen from Viçosa with everted terminalia) with paraprocts 1.25× as long as gonocoxites; each gonocoxite with three ventral lobes; gonostyli inserted at top of gonocoxites.    Comments. There was no consistent difference in the morphology of tegmen and penis between specimens with different dorsal coloration and length of dorsal bristles, and such variation occurred within the populations throughout the geographic extension of the species. Therefore, we consider that the abovementioned specimens all belong to a single species. After the description of C. pallidus, Mellié (1849: 247) wrote "Provient de Bahia; a été donné à M. Reiche par M. Mocquerys de Rouen", a statement in the singular, suggesting that he had only one specimen at the time of the description. It is important to note that Mellié, in the same work, clearly used plural in case he had examined two or more specimens. Therefore, we consider the single type specimen located in the MNHN as the holotype, even though it has a lectotype label. Two specimens from MACN, pinned at the same card, have the same locality label of the type series of C. semipallidus, but these do not have any indication whether they were examined or not by Maurice Pic. Thus we think they do not belong to the type series but they were possibly collected together. The specimen from the MNHN labeled "(…) Bahia (Tabacs) A. Grouvelle (…)" is possibly from Recôncavo Baiano (Fig. 45, question mark), a name for the geographic area around Bay of All Saints, the biggest bay at the northeastern coast of Brazil. The collector Antoine Grouvelle was the director of the "Manufactures nationales des Tabacs" (national manufacturers of tobacco) and used to catch small insects in the tobacco leaves exported to France. These insects, mostly Coleoptera, were probably retained during their flight by the more or less abundant pubescence and viscosity which covers the tobacco leaves; it is also possible that some of them had been attracted by the rainwater which remains in the axils of the leaves, and that others came from the washing water in the country of production (Régimbart 1895). In the 19 th century, most of the tobacco production from Bahia came from Recôncavo Baiano; therefore, we consider that it is plausible that this specimen of C. pallidus has come from this area.