Alterosa araras, Novais & Dumas & Nessimian, 2019

Novais, Christina, Dumas, Leandro Lourenço & Nessimian, Jorge Luiz, 2019, Two new species and a new distributional record of Alterosa (Trichoptera: Philopotamidae) from southeastern Brazil, Papéis Avulsos de Zoologia 59, pp. 1-7 : 2-4

Alterosa araras , new species

( Figs. 2 A‑2D)

Diagnosis: Alterosa araras sp.nov. clearly belongs to guapimirim group, as defined by Blahnik (2005), and shares many similarities with A. guapimirim Blahnik (2005) and A. orgaosensis Blahnik (2005) . All of them have a similarly developed, bulbously enlarged tergum X, with a basolateral projection; similar preanal appendages with a cupped apex bearing a spine-like seta; and similarly shaped inferior appendages, with second articles much shorter than the first. The new species resembles A. guapimirim in having sclerotized intermediate appendages, with several spines apically, but they are shorter and less developed in A. araras sp. nov. than in A. guapimirim . Alterosa araras sp. nov. also resembles A. orgaosensis in the shape of the preanal appendages, which are thinner in both species, as viewed laterally, than those of A. guapimirim . However, in the new species they have an extra stout, spine-like seta at midlength, absent in both A. orgaosensis and A. guapimirim . Additionally, A. araras sp. nov. can be distinguished from both by the general shape of tergum X, especially by its much more well-developed basolateral projection.

Description: Adult: Color (in alcohol) golden-brown; legs, palps, and antennae pale-brown, forewing color pattern not discernible. Male forewings 7.20 mm (n = 10; holotype = 7.20 mm). Maxillary palps 5-articulated; 2 nd article with elongate setae at apicomesal portion; 3 rd article about 2x length of 2 nd; 5 th article elongate, about 2.5x length of 3 rd. Head setal warts well-developed, frontal setal warts large, rounded; anteromesal setal warts laterally fused to anterior setal wart, M-shaped; posterior setal wart subtriangular; posterolateral setal warts large, robust and about ovoid. Tibial spurs formula: 2-4-4. Wing venation typical for the genus; forewings with forks I-V present, discoidal and thyridial cells similar in length; hind wings with forks I-III and V presents.

Male genitalia: Tergum VIII posteromesal margin with a shallow U-shaped emargination/incision. Sternum IX with anterolateral margin forming a moderately rounded projection in dorsal half; posteroventral margin slightly produced, forming broadly rounded expansion ( Fig. 2A ). Tergum IX reduced,forming a mesal projection over base of tergum X, projection prominent, apex subtruncate in lateral view and rounded, subspatulate as viewed dorsally ( Fig. 2B ). Tergum X with lateral margins sinuous in lateral view, subparallel as viewed dorsally, apex rounded and sensillate, forming greatly enlarged expansion in apical half as viewed laterally; dorsally with longitudinal mesal ridge, well-developed and slightly crenulated as viewed laterally ( Figs. 2A, 2B ); tergum basolaterally with well-developed setose projection, foot-like, placed in a large, sclerotized concave depression ( Figs. 2A, 2B ). Intermediate appendages about half length of preanal appendages, rod-like, strongly sclerotized; apex with several apical spines ( Figs. 2A, 2B ). Preanal appendages elongate, narrow and mesally curved; apex and mesal portion both with a single spine-like seta in a concavity (left appendage with an extra subapical small spinelike seta in holotype) ( Figs. 2A, 2B ). Inferior appendages setose, elongate, about linear, flattened on mesal surface; first article, laterally, approximately 2 times as long as wide; second article shorter than first (less than half length), base narrower than apex of first article, slightly constricted mesally, apex rounded with prominent pad of short, stiff apicomesal setae ( Figs. 2A, 2C ). Phallobase elongate and tubular, strongly curved near middle; endotheca with paired spines – 2 apical pairs and 1 basal pair very large and curved – and 2 isolated spines.

Holotype male: BRAZIL: Rio de Janeiro: Petrópolis, Araras, REBIO Araras , Rio Araras , Trilha do Caneco (ponte), 22°26’13.8”S, 43°15’37.4”W, 17.xi-13.xii.2018, 1,086 m, C Novais, LL Dumas, JL Nessimian & AA Alves leg. ( DZRJ).

Paratypes: BRAZIL: Rio de Janeiro: same data as holotype, 4 males ( DZRJ) ; same locality as holotype, 20.iii-13.iv.2018, C Novais, LL Dumas, JL Nessimian & ALD Ferreira leg., 2 males ( DZRJ) ; same locality as holotype, 13.iv-07.v.2018, C Novais, LL Dumas, JL Nessimian & ALH Oliveira leg., 1 male ( DZRJ) ; Petrópolis, Araras, REBIO Araras, Rio Araras , Trilha do Caneco (acima da captação de água), 22°26’15.8”S, 43°15’37.7”W, 13.iv.2018, 1,104 m, C Novais, LL Dumas, JL Nessimian & ALD Ferreira leg., 1 male ( DZRJ) ; Petrópolis, Araras, REBIO Araras, Rio Araras , trilha da represa (pequena cachoeira acima da gruta), 22°26’19.1”S, 43°15’40.9”W, 13.xii.2018, 1,124 m, AA Alves leg., 5 males ( DZRJ) ; Petrópolis, Araras, REBIO Araras, Rio Araras , trilha da represa (pequena cachoeira acima da gruta), 22°26’19.1”S, 43°15’40.9”W, 14.xii.2018, 1,124 m, C Novais, LL Dumas, JL Nessimian & AA Alves leg., 11 males ( DZRJ) ; Petrópolis, Araras, REBIO Araras, Rio Araras , trilha da represa (represa), 22°26’20.0”S, 43°15’42.4”W, 14.xii.2018, 1,123 m, C Novais, LL Dumas, JL Nessimian & AA Alves leg., 2 males ( DZRJ) .

Distribution: Brazil (RJ).

Etymology: The new species is named araras (a noun in apposition) in allusion to the Reserva Biológica de Araras, a beautiful Atlantic Forest reserve where the types specimens were collected.

Remarks: Alterosa araras sp. nov. is very similar and probably closely related to A. guapimirim and A. orgaosensis . Blahnik (2005) in the original descriptions of A. guapimirim and A. orgaosensis claimed that it is possible that the two species may eventually prove to be not specifically distinct.We therefore carefully examined and compared A. araras sp. nov. with the holotypes of previous described species, which are deposited in Museu de Zoologia de São Paulo (MZSP), choosing describe it as a new species. The new species can be recognized based on morphology of male genital structure, as discussed above. We think that these species represent a species complex, possibly contemporaneously diverged. However, further studies using analysis of DNA sequence may be useful in determining whether they form a species complex or whether they are a single polymorphic species.

Figures

Figure 2. Alterosaararas,new species,male genitalia.(A) lateral view; (B) dorsal view;(C) ventral view; (D) phallic apparatus,left lateral view.Scale = 0.25 mm..