The genus Alterosa Blahnik, 2005 (Trichoptera, Philopotamidae, Philopotaminae) in northeastern Brazil, including the description of three new species and an identification key for the genus

Abstract Alterosa Blahnik, 2005 contains 35 described species distributed in southern and southeastern Brazil. Three new species of Alterosa from northeastern Brazil are described and illustrated, Alterosa amadoi sp. n., Alterosa castroalvesi sp. n. and Alterosa caymmii sp. n., the first records of the genus from northeastern Brazil. An identification key for all known species of the genus is also presented.

The genus Alterosa was originally described by Blahnik (2005) to include 2 previously described species, Dolophilodes (Sortosa) sanctipauli Flint, 1971 and Dolophilodes (Sortosa) marinonii Almeida & Duarte, 2003, and 20 new species, totaling 22 species. More recently, 13 new species were described by Jardim and Dumas (2012) and Dumas and Nessimian (2013), raising the total to 35 species distributed exclusively in south and southeastern Brazil. These species are usually found in pristine headwaters and rapids of streams or small rivers in the Atlantic Forest; they are rarely encountered near large rivers. Despite the recent increase in the number of species known from the country, the Brazilian diversity of Alterosa seems to be greatly underestimated, with many more unknown species remaining to be collected. Additionally, there is a lack of knowledge of most aspects of the biology, ecology and distribution of the species, including their immature stages, which are unknown.
In this paper we provide descriptions, diagnoses and illustrations of 3 new species of Alterosa from Bahia state, the first records from northeastern Brazil. In addition, we provide an identification key for all known species of the genus.

Material and methods
The specimens were collected with UV light pan traps (Calor and Mariano 2012) and preserved in 70% ethanol. In order to observe the genital structures, the abdomen of each specimen was removed and cleared in a heated lactic acid 85% solution, followed by a rinse in distilled water, transferred to a solution of 95% EtOH, and mounted temporarily in glycerin or glycerin jelly on a slide for viewing and drawing . After that, removed abdomens were transferred back to alcohol and stored permanently in micro vials with 80% EtOH. A Zeiss stereomicroscope and a Zeiss optical microscope, each equipped with a camera lucida, were used to observe specimens. Genitaia were drawn in pencil and drawings were inked with a technical pen and light table. Females were not illustrated because the minor differences among them were not diagnostic. The terminology used in the descriptions follows that of Blahnik (2005). However, unlike A. ruschii and A. spiesae, the 2 new species cannot be placed in or even near the A. sanctipauli group because of the lack of a basal rounded protuberance on tergum X, with cuticle scabrously developed, and the absence of a crest-like process at the apex of tergum X. Alterosa amadoi sp. n. can be diagnosed by the overall shape of the intermediate appendages, especially the rod-like mesal branch with spines at its apex, and the inferior appendages with the 1st article short and nearly as wide as long. An additional diagnostically unique character for this new species is the dorsal spiny crest-like projection at midlength of tergum X.
Male genitalia. Tergum VIII with posteromesal margin moderately emarginate; emargination U-shaped and extending no more than halfway to anterior margin. Sternum IX with anterolateral margin weakly rounded, subtruncate; posteroventral margin greatly produced, extending nearly linearly from dorsum (Fig. 1A). Tergum IX greatly reduced, membranous or fused to base of tergum X (Fig. 1B). Tergum X tapered from base in lateral view; dorsally with spiny crest-like projection at midlength; apex sensillate, subtruncate, slightly enlarged in lateral view (Figs 1A,1B). Intermediate appendages heavily sclerotized, branched subbasally; mesal branch elongate, surpassing preanal appendages, rod-like, blunt and with small spines apically; lateral branch lobe-like, rounded, covered by spine-like setae, subacute apically in dorsal view, apex greatly enlarged and rounded as viewed laterally (Figs 1A,1B). Preanal appendages elongate, club-like, covered with stiff, small setae; apex rounded with elongate subacuminate projection bearing small apical setae as viewed laterally and dorsally (Figs 1A,1B). Inferior appendages robust, setose; 1st article, in lateral view, short, nearly as wide as long, bulging mesally; 2nd article longer than 1st article, relatively wide, base as wide as apex of 1st article, slightly enlarged apically and with small pad of short, stiff apicomesal setae (Figs 1A,1C). Phallobase tubular, relatively short, slightly curved; endotheca without spines; phallotremal sclerites indistinct (Fig. 1D Distribution. Brazil (Bahia). Etymology. The species is dedicated to the deceased Brazilian writer Jorge Amado, who was born in Bahia state in 1912 and died in 2001. Amado is one of the most acclaimed contemporary Brazilian novelists, whose 32 novels have sold millions of copies. Among his best-known works are "Capitães de Areia", "Gabriela, Cravo e Canela", and "Tieta do Agreste". In 2012, Brazil celebrated the centenary of his birth.
Alterosa castroalvesi sp. n. urn:lsid:zoobank.org:act:04FB0169-E8AF-4E54-9F01-3DF278EA1B19 http://species-id.net/wiki/Alterosa_castroalvesi Figs 2A-D Remarks. Alterosa castroalvesi sp. n. is closely related to Alterosa truncata Blahnik 2005, resembling that species in the broadened and truncate apices of the inferior appendages, the elongate, narrow, and arched intermediate appendages, each terminating in a very prominent apical lance-like seta, and the general structure of preanal appendages. Additionally, the general structure of tergum X with paired longitudinal, serrate ridges, is also similar between these species. It differs in that the intermediate appendages in A. castroalvesi sp. n. have 2 prominent lance-like setae, the usual apical 1 and an additional 1 at the apical third. Alterosa castroalvesi sp. n. also differs from A. truncata in the length of 2nd article of preanal appendages, that is relatively shorter in the new species. The differences are relatively minor and it is possible that the 2 species may eventually prove to be not specifically distinct. As A. truncata, the new species probably belongs to A. sanctipauli Group, as defined by Blahnik (2005).
Male genitalia. Tergum VIII with posteromesal margin deeply emarginate, emargination V-shaped and extending more than half way to anterior margin. Sternum IX with anterolateral margins broadly rounded; posteroventral margin greatly produced, forming broadly rounded expansion ( Fig. 2A). Tergum IX greatly reduced, membranous or fused to base of tergum X (Fig. 2B). Tergum X narrow, wider at base, lateral margins subparallel in dorsal view; dorsally with mesally divided crest-like projection near base, with spine-like projections along each side of divided margin; apex sensillate, rounded as viewed dorsally, rounded and slightly enlarged in lateral view (Figs 2A, 2B). Intermediate appendages heavily sclerotized, elongate, extending past preanal appendages, rod-like, curved at base, narrowly paralleling lateral margins of tergum X; intermediate appendages with small projection at apical third bearing 1 apical lance-like seta; apex acute, terminating in apical lance-like seta (Figs 2A, 2B). Preanal appendages narrow, constricted basally, moderately elongate, not greatly modified, covered with scant setae and numerous minute spine-like setae; apex rounded, without apical setae, with 1 short preapical projection from the ventral surface, fringed apically with minute spines (Figs 2A,2B). Inferior appendages elongate, linear, flattened on mesal surface, setose; each with 1st article, in lateral view, approximately 2 times as long as wide, tapering apically; 2nd article slightly shorter than 1st article, moderately wide, nearly as wide at base as apex of 1st article, apex enlarged and subtruncate, with fringing pad of short, stiff apicomesal setae ( Paratypes: BRAZIL: Bahia: same data as holotype, 2 males (DZRJ 3797), 1 male (UFBA).

Distribution. Brazil (Bahia).
Etymology. This species is named in memory of Antônio Frederico de Castro Alves, known as "the poet of the slaves" because of his sympathy for the Brazilian abolitionist cause. Castro Alves was born in Bahia state in 1847 and died at 1871. He is the patron of the 7th chair of the Brazilian Academy of Letters. Some of his abolitionist poems, like "Espumas Flutuantes", "A Cachoeira de Paulo Afonso", and "O Navio Negreiro", were collected in a posthumous book called "Os Escravos", published in 1883.
Alterosa caymmii sp. n. urn:lsid:zoobank.org:act:51728D88-1218-4C1A-ADDF-FED6872BBE77 http://species-id.net/wiki/Alterosa_caymmii Figs 3A-F Remarks. Alterosa caymmii sp. n. is very similar to Alterosa amadoi sp. n., as discussed under that species. It differs in that the lateral branch of each intermediate appendage is apically projecting in A. caymmii sp. n., while in A. amadoi sp. n. it is broadly rounded. Alterosa caymmii sp. n. also differs from A. amadoi sp. n. in the shape of inferior appendages. Additionally, the phallus of A. caymmii sp. n. is more developed, with endotheca bearing several tracts of numerous large spines.
Etymology. This species is named in memory of Dorival Caymmi, considered one of the most important Brazilian songwriters. Caymmi was born in Bahia state in 1914 and died at 2008. He became a national icon with his lyrics that evoked the charm of Bahia's fishing villages, beaches and beautiful women, like "O Que é Que a Baiana Tem?", "Marina", "Rainha do Mar", "Samba da Minha Terra", among others.