Loxinum Navas
Creators: name: Prather Table Of Contents, Aysha L.
Publisher: name: Zenodo
Year: 2004
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Trichoptera
Calamoceratidae
Loxinum

description: Genus Loxinum Navás
Loxinum Navás 1934b:175 [Type species: Loxinum aequatorium Navás 1934b, original designation]. — Flint 1983:77 [as synonym of Banyallarga]
Navás (1934b) described Loxinum aequatorium from Ecuador —based on a single female specimen, which is now lost—as a calamoceratid. The only illustration in his description is of the forewing; characters of the head, wings, and legs are described in the text. The palps are described as long, with the first segment short; the remaining segments long. The forewing illustrated and described possesses only forks I, II, III, and V. The same forks are present in the hind wing. The tibial spurs are 2, 4, 4. "Short" as a descriptor of the first maxillary palp segment is ambiguous (in calamoceratids the first and second segments are of approximately equal length, and several times longer than wide). All known calamoceratids retain fork IV in the forewing of both sexes. Flint (1983) argued that Navás had omitted to draw or mention in the text fork IV, and synonymized Loxinum with Banyallarga. However, it may be argued that the possession of that character was not necessarily required by Navás's concept of Calamoceratidae — Navás (1931) also described the African genus Silvatares —which Prather & Holzenthal (2002) examined and determined to belong to Pisuliidae —in Calamoceratidae, and neither does it have forewing fork IV.
The venation of the wing illustrated appears most similar to that of species in the genus Chimarrhodella (Philopotamidae). I compared Navás' illustration with Blahnik & Holzenthal's (1992) illustration of Chimarrhodella galeata (Martynov) and specimens of C. tapanti Blahnik & Holzenthal 1992 and C. ulmeri (Ross 1956). The wings appear very similar in shape, and the crossveins forming the chord are lined up vertically in Loxinum and Chimarrhodella. There are certain differences: 1) crossvein r is at the bases of forks I and II in C. aequatoria, while it attaches more distally to M 2 in the three Chimarrhodella species examined; 2) crossvein m­cu also is placed more distally in C. aequatoria. Navás wrote that he used Ulmer's (1907) key. He would have had to make two errors in keying his specimen if he was looking at a Chimarrhodella: 1) he would have interpreted the terminal maxillary palp segment as non­annulate (on a pinned specimen this is not always easy to determine); and 2) he would have missed the ocelli (which in Chimarrhodella are small and easily obscured by setae on the head). Navás's description and illustration, such as they are, are consistent with Blahnik & Holzenthal's (1992) diagnosis of Chimarrhodella, and contradictory to the diagnosis of Calamoceratidae. Therefore, I am transferring this species to Chimarrhodella, NEW COMBINATION; as aequatorium is the type species of Loxinum, the latter becomes a junior synonym of Chimarrhodella, NEW SYNONYM.
description: Published as part of Prather Table Of Contents, Aysha L., 2004, Revision of the Neotropical caddisfly genus Banyallarga (Trichoptera: Calamoceratidae), pp. 1-76 in Zootaxa 435 (1) on page 9, DOI: 10.11646/zootaxa.435.1.1, http://zenodo.org/record/5028097