Macrelmis granigera

Passos, Maria Inês Silva Dos, Miranda, Gustavo Silva De & Nessimian, Jorge Luiz, 2015, Three new species of Macrelmis Motschulsky (Coleoptera: Elmidae: Elminae) from Southeastern Brazil with new definition of species groups to the genus, Zootaxa 4058 (2), pp. 195-210 : 205

granigera species group Hinton 1940

Diagnostic character: aedeagus with truncated apex, and with a constriction two thirds before the apex ( Figs. 4A – C ).

Species: Macrelmis granigera , M. scutellaris and M. shoemakei .

Distribution ( Fig. 7 ): Costa Rica: Cache ( Sharp 1882). Mexico: Temascaltepec ( Hinton 1934; Hinton 1940), Coahuila ( Brown 1971). USA: Texas ( Brown 1971).

History of the group: Hinton (1940) stated that M. granigera and M. scutellaris form a group characterized by pronotum with a prominent gibbosity in front of the scutellum. Additionally, Hinton (1940) described some larval characters that supported the group, such as "a short but prominent median longitudinal carina on the base of both the metasternum and the first abdominal sternite". Hinton (1945) added M. germaini , M. peruviana and M. amazonica to the group and emmended that all species have elytron apex obliquely truncate, except for M. scutellaris . Manzo (2003) included one more species, M. saltensis , which also has pronotum with gibbosity. M. bispo was the last species added to this group due its "obovate gibbosity near the middle of pronotal base" ( Barbosa et al. 2013). Despite the external similarities of these species (gibbosity on pronotum), the male genitalia of most of them is completely different, so, according to the current definition, species with different shape of genitalia should not be included in the group. M. peruviana was described based on a female and a redescription was never carried out; so, according to our proposed organization of the groups, it cannot be placed in any of them. M. saltensis has a unique aedeagal morphology and should be considered as belonging to its own group, also taking into account its tibia unusual shape, which is unique in the genus. M. bispo has an unusual shape of male aedeagus as well and should have its own group. M. germaini does not have description and illustration of the male genitalia, so, according to our organization, it should not be included until its proper publication.

Figures

FIGURE 7. Distributional map of North and Central American species of Macrelmis. The species are shown separately to facilitate visualization. All maps are all in the same scale as the last one (bottom right).

FIGURE 4 A – F. Male genitalia of Macrelmis. A – C. granigera sp. group. A. M. granigera. B. M. scutellaris (both modified from Hinton, 1940). C. M. shoemakei (modified from Brown, 1971). D – F. striata sp. group. D. M. striata (modified from Hinton, 1940). E. M. sandersoni. F. M. striatoidea (both modified from Hinton, 1936 a). Scale bars: 0.1 mm.