Chimarra (Chimarrita) singularis, Desidério & Barcelos-Silva & Hamada, 2018

Desidério, Gleison Robson, Barcelos-Silva, Patrik & Hamada, Neusa, 2018, New species, records, and immature stages of Chimarra Stephens (Trichoptera: Philopotamidae) from Campos Amazônicos National Park, northern Brazil, Zootaxa 4500 (2), pp. 258-270 : 259-260

publication ID	https://doi.org/ 10.11646/zootaxa.4500.2.6
publication LSID	lsid:zoobank.org:pub:499EE392-D9DF-4744-B86B-52D1E7242B94
persistent identifier	https://treatment.plazi.org/id/27D98826-2897-4DD7-BC6E-C6C742BBC6C0
taxon LSID	lsid:zoobank.org:act:27D98826-2897-4DD7-BC6E-C6C742BBC6C0
treatment provided by	Felipe
scientific name	Chimarra (Chimarrita) singularis
status	sp. nov.

Treatment

Chimarra (Chimarrita) singularis sp. nov.

( Figures 2A–2G View FIGURE 2 )

Material examined. Holotype male. BRAZIL: Amazonas : Manicoré, Campos Amazônicos National Park,

confluence of the Igarapé do Veado with the Rio Macaco, 08°25'23.9''S, 61°42'02.9''W, 79 m a.s.l., 04.vii.2017, N. Hamada, G. R GoogleMaps . Desidério, P. V . Cruz, J.O. Silva legs., sheet LED light ( INPA) .

Diagnosis. Chimarra (Chimarrita) singularis sp. nov. male resembles that of C. (Chimarrita) xingu Blahnik 1997 by sharing prominent dorsal ridges on segment IX. However, in the new species these structures are covered with short fine setae. The new species also has a pair of mesal, arrow-shaped ridges on segment IX that are strongly sclerotized, while in C. xingu the ridges are differently shaped, converge posteriorly, and are lightly sclerotized. Additionally, C. singularis sp. nov. can be easily distinguished from all other species in the subgenus by the small, dark, rounded subapical lobe on the mesal surface of each inferior appendage.

Description. Male adult. Forewing length 3.1 mm (n = 1). Overall color (in alcohol) nearly uniformly pale brown, palps dark; thorax ventrally, meso- and metacoxae yellowish; antennae indistinctly annulated ( Fig. 2A View FIGURE 2 ). Head very short and somewhat flattened; anteromesal and anterior setal warts with tufts of yellow setae; posterolateral setal warts with tufts of dark setae; posterior parietal sclerite narrowly meeting on posterolateral portion, slightly extending below eye. Maxillary palps relatively short, 2nd segment longer than 3rd segment, apicomesally with stout setae ( Fig. 2B View FIGURE 2 ). Forewing venation typical for the subgenus; Rs straight; crossveins r, s, and r-m nearly linearly arranged and unpigmented, crossvein m-cu and apex of Cu2 also hyaline; A2 with apparent apical “fork,” that to A1 elongate and broadly rounded and that to A3 shortest ( Fig. 2C View FIGURE 2 1 View FIGURE 1 ). Hind wing: R1 not fused to Sc; Rs 4-branched, M 3-branched ( Fig. 2C 2 View FIGURE 2 ). Male pretarsal claws symmetrical, unmodified.

Male genitalia. Segment IX synsclerous, in dorsal view slightly longer than wide; anterodorsal margin slightly convex; dorsally with mesal and dorsolateral ridges from posterior to anterior margins, spaces among them covered with many short fine setae, mesal pair of ridges arrow-shaped strongly sclerotized ( Fig. 2E View FIGURE 2 ); their posterolateral margins angularly projecting at level of bases of inferior appendages, apex rounded; in ventral view anteroventral margin expanded, with apex rounded; in lateral view ventral process elongate, narrow, acute, almost straight ( Fig. 2D View FIGURE 2 ). Tergum X short, fused to segment IX; in dorsal view, apex with deep U-shaped mesal excision, extending about ½ length of tergum, forming narrow paired lateral lobes with acute and mesad-directed apices ( Fig. 2E View FIGURE 2 ); apical lobes and lateral margins of tergum with numerous sensilla ( Fig. 2D View FIGURE 2 ). Preanal appendages very small, rounded, fused to terga near base of tergum X ( Figs. 2D, 2E View FIGURE 2 ). Inferior appendages of moderate length, in lateral view, each nearly linear, slightly inflated basoventrally, subtruncate apically ( Fig. 2D View FIGURE 2 ); in dorsal or ventral views, widest basally and narrowing in apical half; apex rounded, with small, dark, rounded subapical lobe on mesal surface ( Figs. 2F View FIGURE 2 1 View FIGURE 1 , 2F 2 View FIGURE 2 ). Phallotheca elongate, tubular, with rounded phallobase and distinct apicoventral extension; phallic spine single, stout, curved, elongate (subequal in length to phallotheca), emerging ventrally near phallobase; apex of phallotheca ventrally projecting, angularly truncate, pointed; endotheca elongate, slightly inflated in basal half ( Fig. 2G View FIGURE 2 ); phallotremal sclerite complex evident as two sclerotized pieces: (1) elongate, slender rod at base of endotheca, and (2) claw-shaped sclerite apically ( Fig. 2G View FIGURE 2 ).

Female and immature stages. Unknown.

Etymology. The specific epithet is an allusion to the distinct morphology of the inferior appendages of this species. Derived from the Latin, singularis means “characteristic, unique, remarkable.”

Remarks. Chimarra (Chimarrita) is currently divided into two species groups ( Blahnik 1997; Kjer et al. 2014): the C. (Chimarrita) rosalesi Group (7 species) and the C. (Chimarrita) simpliciforma Group (14 species, including the new species described here). Species in the latter group are recognized by having the male phallic apparatus with a single, elongate spine emerging basodorsally from the phallotheca. Females in this group bear a ventral process on sternum VII, reduced or absent apodemes on segment IX, and tergum and sternum IX both elongate ( Blahnik 1997). All species in the simpliciforma Group occur in Brazil, mainly distributed in the Southeast region: ( C. camella Blahnik 1997 , C. camura Blahnik 1997 , C. curvipenis Blahnik & Holzenthal 2012 , C. heligma Blahnik 1997 , C. kontilos Blahnik 1997 , C. latiforceps Blahnik & Holzenthal 2012 , C. majuscula Blahnik 1997 ), Amazon Basin ( C. akantha Blahnik 1997 , C. heppneri Blahnik 1997 , C. simpliciforma Blahnik 1997 , C. tortuosa Blahnik 1997 , C. xingu ); and a few in the Northeast region: ( C. anticheira Vilarino & Calor 2015 , C. heppneri , C. kontilos ).