Cyrnellus guyanensis Rueda Martín & Gibon & Sganga 2021, new species
Creators: name: Rueda Martín, Paola A.
name: Gibon, Francois-Marie
name: Sganga, Julieta V.
Publisher: name: Zenodo
Year: 2021
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Trichoptera
Polycentropodidae
Cyrnellus
Cyrnellus guyanensis

description: Cyrnellus guyanensis new species
Figs 2A–2D
Diagnosis. Cyrnellus guyanensis can be distinguished from other Cyrnellus species by the following character combination: The apex of each inferior appendage is as wide as the median part (Fig. 2A, ia), with two subapicomesal spines dorsoventrally flat (depressed, Fig. 2B, asI, asII), and lacking an internal lobe; the anterior arm of the dorsal phallic sclerite is thick (Figs 2C, 2D, ds), the posterior arms are divergent, short and slender (Fig. 2D, ds). Cyrnellus guyanensis is most similar to C. ulmeri Flint 1971. The difference in size is important, the length of each forewing is 5 mm in C. ulmeri whereas it is 3.8 mm in C. guyanensis. The genitalia of C. guyanensis are distinguished from those of C. ulmeri by the apex of each inferior appendage being as wide as the median part (whereas it is apically broadened in C. ulmeri); the subapicomesal spines are flat (conical in C. ulmeri); an internal lobe of each inferior appendage is absent (present in C. ulmeri); the anterior arm of the dorsal phallic sclerite is reduced (absent in C. ulmeri); and the posterior arms of the dorsal phallic sclerite are divergent, short, and slender (fused and forming a tube in C. ulmeri).
Description. Adult: Length of each male forewing 3.8 mm. General coloration light brown.
Male genitalia. Anterior margins of sternite IX sinuous; posterolateral margins irregular, each with acute projection (Fig. 2A, ix). Width of intermediate appendage constant from base to apex, with dorsal and ventral margins parallel (Fig. 2A, iap). Preanal appendages each with mesolateral process narrow at base (Fig. 2A, mlp); dorsolateral process subequal in length to mesolateral process, slightly curved, directed distad (Fig. 2A, dlp); mesoventral process wide at base, gradually tapered to blunt apex (Fig. 2A, mvp). Inferior appendages long, each with dorsal and ventral margins sinuous, parallel (Fig. 2A, ia); apex slightly curved toward midline, subapicomesal lobe high, bearing two flat, triangular spines with broad bases at 2/3 length of inferior appendage (Fig. 2B, ap, asI, asII); internal lobe absent (Fig. 2B). Phallus tubular; dorsal phallic sclerite Y-shaped, with anterior arm thick and posterior arms divergent, short, and slender (Fig. 2D, ds).
Discussion. This species was discovered among specimens of the USNM identified as Cyrnellus ulmeri. These two species are very similar. Both have two subapicomesal spines I (asI), inserted at mid-length of each inferior appendage. Even though the genitalia of C. guyanensis n. sp. and C. ulmeri are similar, some constant differences clearly distinguish the two species.
Material examined. Holotype: Male: GUYANA: Mazaruni, Potaro District, Takutu Mountains, 6°15´N, 59°5´W, 17.xii.1983, at blacklight in forest clearing near streams, Earthwatch Research Expedition, P.J. Spangler & W.E. Steiner (USNM).
Paratypes: 9 males, same data as holotype. BRAZIL: Para: Rio Oriri Camp., 52°40´W, 3°50´S, Altamira, Ca 1000Km, 17–18.x.1986, P. Spangler & O.S, Flint, 2 males (USNM).
Etymology. The name is a Latin adjective referring to the type country (Guyana).
Distribution. Brazil, Guyana.
description: Published as part of 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, pp. 15-29 in Zootaxa 5082 (1) on page 18, DOI: 10.11646/zootaxa.5082.1.2, http://zenodo.org/record/5783094