Aymaradella boliviana, Holzenthal, Ralph W., Blahnik, Roger J. & Rios-Touma, Blanca, 2018

Holzenthal, Ralph W., Blahnik, Roger J. & Rios-Touma, Blanca, 2018, New species and a new genus of Philopotamidae from the Andes of Bolivia and Ecuador (Insecta, Trichoptera), ZooKeys 780, pp. 89-108 : 89

Aymaradella boliviana sp. n. Figs 1, 2, 3

Diagnosis.

Diagnosed by the characteristics of the genus as discussed above.

Description.

Adult. Forewing length (male) 5.5-5.8 mm (n = 2); (female) 5.8-6.3 mm (n = 2). Spur formula 2:4:4. Overall color, including wings and antennae, light brown, legs yellowish brown. Head short and rounded, eyes with short setae between facets, postparietal sclerite short (ca. ½ diameter of eye). Palps short; maxillary palp with segment I very short, segments II and IV short, II with apicomesal bristles, III only moderately elongate, V longer than III. Forewing with forks I-V, hind wing with forks I-III and V (IV absent). Forewing with discoidal cell relatively short, forks I and II approximately sessile, crossveins s, r-m, and m hyaline and nearly linear, 3A looped to 2A, 2A to 1A, intersecting in proximal half of vein. Fork I of hind wing with short stem, fork II sessile, 1A and 3A intersecting wing margin, 2A missing.

Male. Abdomen with segments through VII with sternites generally setose, tergites V-VII with setae confined to (more or less) linear row on posterior margin, each seta with more or less evident, desclerotized area at base. Sternum VII with short rounded mesoventral process from posterior margin, directed posterad and positioned posterior to sclerotized line that extends near the posterior margin from the mesoventral process to midlateral margin of sternite. Segment VIII synscleritous, ventrally ca. ½ length of sternite VII, widening anterodorsally to width subequal to tergum VII; as viewed dorsally, with anterior margin concavely invaginated, mesally with pair of elongate, narrow, sclerotized processes, with apices acutely narrowed and somewhat laterally projecting, extending from near anterior margin of segment beyond posterior margin of segment IX; dorsomesal part of segment, from lateral margin of posteromesal invagination to posterior of segment, only weakly sclerotized or submembranous. Segment IX synscleritous, ventral margin subequal in length to sternum VIII, evenly narrowed from posterior margin to narrow, sclerotized, invaginated, dorsomesal strap; posterior of segment weakly sclerotized or submembranous. Tergum X simple in structure, elongate, narrow, slightly widened near base and uniformly narrowed apically; apex rounded, basally with pair of small rounded protuberances, each with 2-3 short stiff setae; dorsal surface with short setae or seta-like sensilla, declining in size apically, extreme apex with cluster of small sensilla. Preanal appendages elongate, narrow, emerging near base of tergum X; as viewed dorsally, somewhat mesally curved, emerging near base of tergum X. Inferior appendages elongate and relatively narrow, widest near base of basal segment; apex of apical segment slightly widened, with cluster of short, stiff setae on apicomesal surface. Phallic apparatus with phallobase more or less tubular, with usual basodorsal projection, relatively short, simple, tapering from base to apex; phallotremal sclerite small, indistinct, endotheca simple, without associated spines or ornamentation.

Female. Genitalia very elongate, tapering from segment VII; segment VII much longer than preceding segment (ca. 1½ x length), ventral margin with very small, acute, mesoventral process at midlength; segment VIII nearly as long as segment VII, tapering, not synscleritous, sternite with lateral pair of very elongate, narrow apodemes, extending from anterdorsal margin, apodemes nearly 1½ x length of segment VII. Segment IX very short, (apparently comprised of tergum only), anterolateral margin with pair of very elongate, narrow apodemes, extending anterad, length ca. 1½ x length of segment VIII; posterior margin with pair of elongate, narrow sensillate lobes (segment X), each with short apical cercus. Vaginal apparatus membranous, only indistinctly evident.

Holotype.

Male. BOLIVIA: La Paz: quebrada del Río Zongo, 1400 m, 24-30.x.1984, L.E. Peña G. (UMSP000136162) (NMNH). Paratypes: same data as holotype, 1 male, 2 females (NMNH); BOLIVIA: La Paz: PN-ANMI [Parque Nacional y Área Natural de Manejo Integrado] Cotapata, Estacíon Biológica Tunquini , Quebrada El Padrini , 16°12.193'S, 67°50.692'W, el. 1343 m, 06-07.xii.2004, Robertson, Valdivia, 9 males, 2 females (UMSP, UASC).

Etymology.

Named for the country where the species was discovered.

Remarks.

The generic placement of this new species from Bolivia, which is unlike other Neotropical species of Philopotaminae, requires a discussion of the world fauna, particularly of the genus Wormaldia .

Wormaldia , in general, has a cosmopolitan distribution, excluding the Australian region. The Central and South American species of the genus agree in general form with other species in the genus ( Muñoz-Quesada and Holzenthal 2015). Wormaldia was treated comprehensively by Ross (1956), who recognized two subgenera, Wormaldia and Doloclanes and a single isolated species from the Philippines, W. recta Ulmer. Ross also treated the genus Gunungiella , which is characterized by apomorphic and often bizarre modifications of the inferior appendages and a reduced venation, namely with forks III and IV of the forewing absent and also with distinctive reductions and modifications of the hind wing. Only a very few species of Gunungiella were known at the time Ross did his revision, but this has changed, especially with a revision of the genus by Schmid (1968), who added 34 new species, mostly from India. Many additional species have been added since then, from India and Southeast Asia to Indonesia (e.g., Huisman 1993, Melnitsky and Ivanov 2010). Ross considered the possibility that W. recta might be related to Gunungiella , primarily because of its loss of fork IV in the forewing. However, Schmid questioned this placement and decided that the unusual species was probably correctly allied with Wormaldia , and thus independently lost fork IV in the forewing. Schmid agreed with Ross that it was a unique and isolated species with many primitive attributes.

The generic name Doloclanes has been variably treated by different authors. The genus was established by Banks (1937) for two species from the Philippines. It was reduced to a subgenus of Wormaldia by Ross (1956), who provided a rather informal diagnosis and recognized nine species in the subgenus, four of them new. He also reduced the generic names of Nanagapetus Tsuda and Gatlinia Ross to synonyms. The latter were based on the species Nanagapetus kisoensis Tsuda and Gatlinia mohri Ross, monotypic genera from Japan and Eastern North America, respectively. Doloclanes was subsequently raised to full generic status by Schmid (1991), who provided a more formal diagnosis and described eleven new species from India. The genus was subsequently reduced to synonymy with Wormaldia by Sun and Malicky (2002), based on the variability they observed concerning Ross’s venational characters in some species (e.g., W. quadriphylla ). They stated that even a subgeneric status was doubtful. However, no mention was made of Schmid’s work and the more extensive list of diagnostic characters he provided. At present, Doloclanes is considered a synonym of Wormaldia , but its status should probably be considered provisional until a more formal assessment is made. The single North American species placed in Doloclanes , W. mohri , was subsequently treated by Muñoz-Quesada and Holzenthal (2008), who considered it a member of the thryia species group of Wormaldia . However, the species rather clearly demonstrates all of the diagnostic criteria used by Schmid to recognize species of Doloclanes . Since none of these characters apply to the new species from Bolivia treated here, it cannot be considered a member of the genus Doloclanes , regardless of its formal status.

Placement of the new species from Bolivia also requires a consideration of the species of Wormaldia from Africa. Ross (1956) placed two African species in what he called the kyana group (in the subgenus Wormaldia ), commenting that they had a peculiar morphology and that they were probably an isolated lineage close to the ancestor of Wormaldia . Additional species from Madagascar and the African mainland have been discovered since then, most with elongate and filamentous preanal appendages. Gibon (2014), in describing a number of new species from Madagascar, subsequently divided the African species into the kyana group, including four mainland African species, and the pauliani group, including eleven species from Madagascar. The Madagascar species seem to consistently lack fork IV in the forewing (as in W. recta from the Philippines), as indicated in illustrations of new species from Madagascar by Johanson (2010). However, at least some mainland species have complete and primitive venation for Philopotamidae .

Given the unusual morphology of W. recta and the African species of Wormaldia , their inclusion in the genus should possibly be reconsidered, especially since the genus is otherwise morphologically uniform and well characterized. It should be noted also that the genus Thylakion , from South Africa, while not having the 2A vein of the forewing obsolete, does have it reduced to a stub, much as in the unrelated genus Chimarrhodella . Thylakion also has processes lateral to tergum X. Its possible relationship to African species of Wormaldia should probably be considered. However, these are questions independent of the placement of our new species from Bolivia. Given the fact that it possesses none of the apomorphic characters of the unusual species of Wormaldia from either the Philippines or Africa, and has an unusual set of characters of its own, we believe that the most reasonable way to treat the taxon is to assign it to a new genus. The designation also points out the need to include the species in subsequent studies of relationships among and within genera of Philopotaminae, which is sorely needed.