Cyrnellus marginalis ( Banks 1930 )

Rueda Martín, Paola A., Gibon, Francois-Marie & Sganga, Julieta V., 2021, New species and records of the Neotropical genus Cyrnellus (Trichoptera: Polycentropodidae) and the re-establishment of C. minimus and C. marginalis, Zootaxa 5082 (1), pp. 15-29 : 20

Cyrnellus marginalis ( Banks 1930)

Figs 3A–3D

Nyctiophylax marginalis Banks 1930: 231 (original description); Ross 1938: 12 (designated male lectotype).

Cyrnellus marginalis Banks ; Ross 1944: 71, 72 (descriptions of male, female); Flint 1964: 469 [as synonym of Cyrnellus fraternus ( Banks 1905) ]; Holzenthal & Calor 2017: 418 (catalogue, as synonym of C. fraternus ).

Cyrnellus zernyi Mosely 1934: 142 (original description); Ross 1938: 13 (synonym of C. marginalis )

Diagnosis. Cyrnellus marginalis is distinguished from other species in the genus by the following character combination: Subapicomesal spine of each inferior appendage conical, wide at base, subapical in position ( Fig. 3B , as); its internal lobe rounded ( Fig. 3B , il); the dorsal phallic sclerite has its anterior arm short ( Fig. 3C , ds) and posterior arms short and divergent ( Fig. 3D , ds). Cyrnellus marginalis is considered to be distinct from C. fraternus by having the base of each intermediate appendage narrower than the median part whereas in C. fraternus the base is subequal to the median part ( Figs 3A, 3E ). Another constant character is the ventral margin of each inferior appendage which is angulate in C. marginalis and sinuous in C. fraternus . An additional remarkable difference between the species is the position of the subapicomesal spine of each inferior appendage: in C. marginalis this spine is subapical by a distance as long as the width of the apex of the appendage ( Fig. 3A ); in C. fraternus the spine’s subapical insertion is more than 1.5 times as far as the width of the apex of the appendage ( Fig. 3F ); this distance is not constant among individuals of the same species ( Figs 3F, 3I–3K ).

Material examined. BOLIVIA: Laguna Granja, Bella Vista , 13°15’50’’S, 63°42’33’’W, 06.v.2006, 1 male (IBN) ; BRAZIL: Rondonia, 62 Km S de Ariquemes, Linea C-20, 7 Km E B- 65, 165 m, Fazenda Rancho Grande , 10°32,5´S, 62° 48´W, 17.xi.1991, Dr Peter, 3 males (USNM) ; GUYANA: Karanambo, Rupununi R., 3°45,1´N, 59°18,6´W, 31.iii–2.iv.1994, MV Light, O.S. Flint Jr., 1 male (USNM); Mazarini Potaro district, Takutu Luber Camp., Takutu Mountains , 6.25°N, 50.0°W, 29.xii.1982, Steiner, Lowry & Williams, 1 male (USNM); Dunulay ranch, Aramanti River , 5°39,4´N, 57°35,5´W, 15–18.iv.1995, O.S. Flint Jr., 1 male (USNM) ; PARAGUAY: Dpto Concepción, Concepción, UV Light trap between 5:45–12:30 PM, warm night 5 days after heavy rain, J.A. Kochalka, 12 males (USNM) ; URUGUAY: Artigas: San Gregorio, orillas del Río Uruguay , light trap, 29.xi.1959, 9 males (CFHCM) ; VENEZUELA: GU, Fundo Masaguaral, Caño Caracol, 19-20.i.1983, O.S. Flint Jr., 1 male (USNM); Río Caroni , at Paso Caruachi , 9.ii.1979, C.M. & O.S. Flint Jr., 1 male (USNM) .

Distribution. Cyrnellus marginalis is distributed in various South American countries but was collected and described for the first time in United States of America by Banks from Put-In-Bay, Ohio. Banks’ material could not be reviewed; his specimen could belong to C. fraternus , but because the two species have been considered synonyms since 1964, all existing North American records are suspect and need to be reviewed. It is reported for the first time from Bolivia. Bolivia new record, Brazil, Guyana, Paraguay, Uruguay, United States of America, Venezuela.

Figures

FIGURE 3. Cyrnellus spp., male genitalia. 3A–3D, Cyrnellus marginalis Banks 1930: 3A, left lateral; 3B, right inferior appendage, ventral; 3C, phallus, left lateral; 3D, phallus, dorsal. 3E–3K, Cyrnellus fraternus (Banks 1905): 3E, left lateral; 3F, right inferior appendage, ventral; 3G, phallus, left lateral; 3H, phallus, dorsal; 3I–3K, variations of the right inferior appendage, ventral. ap = apex of an inferior appendage; as = subapicomesal spine; dlp = dorsolateral process; ds = dorsal phallic sclerite; ia = inferior appendage; iap = intermediate appendage; ix = sternite IX; mlp = mesolateral process; mvp = mesoventral process.