New species and records of Chimarra (Trichoptera, Philopotamidae) from Northeastern Brazil, and an updated key to subgenus Chimarra (Chimarrita)

Abstract Two new species of Chimarra (Chimarrita) are described and illustrated, Chimarra (Chimarrita) mesodonta sp. n. and Chimarra (Chimarrita) anticheira sp. n. from the Chimarra (Chimarrita) rosalesi and Chimarra (Chimarrita) simpliciforma species groups, respectively. The morphological variation of Chimarra (Curgia) morio is also illustrated. Chimarra (Otarrha) odonta and Chimarra (Chimarrita) kontilos are reported to occur in the northeast region of Brazil for the first time. An updated key is provided for males and females of the all species in the subgenus Chimarrita.


Introduction
Philopotamidae Stephens, 1829 is a cosmopolitan family with approximately 1,270 described species in 19 extant genera. The family is comprised of three subfamilies: Rossodinae Özdikmen & Darilmaz, 2008 (endemic to Madagascar, with 16 species); Philo-potaminae Stephens, 1829 (present in all biogeographic regions, >400 species) and the most diverse subfamily, Chimarrinae Rambur, 1842 (cosmopolitan, ca. 800 species). Chimarrinae contains three genera: Edidiehlia Malicky, 1993 (Oriental, monospecific); Chimarrhodella Lestage, 1925 (Neotropical, 12 species); and one of the largest caddisfly genera, Chimarra Stephens 1829 (cosmopolitan, ca. 780 species) . The genus Chimarra is characterized by foretibial spurs reduced to one (spur formula 1:4:4), and by an anal loop in the hindwing, in which the 2A vein is looped to join the 1A vein (Blahnik 1998). Chimarra is divided into four subgenera, the cosmopolitan Chimarra Stephens, 1829, and the three primarily Neotropical subgenera Curgia Walker, 1860, Chimarrita Blahnik, 1997, and Otarrha Blahnik, 2002 analysis confirmed the monophyly of the genus Chimarra and hypothesized an early Cretaceous origin, approximately 138 million years ago. They suggested the genus first arose in the Neotropical region, with a subsequent radiation through the Oriental, Palaearctic and Australasian regions, secondarily to the Nearctic region, and with several independent colonization events in the Afrotropics.
The subgenus Chimarrita was previously divided into 3 species groups by Blahnik (1997): C. (Chimarrita) maldonadoi, C. (Chimarrita) rosalesi and C. (Chimarrita) simpliciforma groups. Recently Kjer et al. (2014) infered a phylogeny of the genus Chimarra using molecular data. Most of the subgeneric groups established by Blahnik based on morphological characters were recovered, but Kjer et al. (2014) did not support the placement of the maldonadoi Group in the subgenus Chimarrita, but rather considered the group incertae sedis, within the genus.
Males in the subgenus bear a partially to nearly separated tergum X, have very short knoblike and basally fused preanal appendages, the anteroventral margin of segment IX projected and tapering, usually to end acute apex, an elongate and narrow ventral process on segment IX, and a phallotheca with several short curved phallic spines or a single elongate spine almost always with slight helical twist. Females belonging to the subgenus Chimarrita can be easily diagnosed by the presence of an elongate tergum IX and segment VIII without anterolateral apodemes.
In this paper descriptions, diagnoses, and illustrations of two new species of Chimarra (Chimarrita) are provided, which fall within the C. rosalesi and C. simpliciforma groups. An updated key for males and females of the subgenus Chimarrita is also presented, and a description of the morphological variations of Chimarra (Curgia) morio. New records of Chimarra (Otarrha) odonta Blahnik, 2002, and Chimarra (Chimarrita) kontilos Blahnik, 1997, are reported for the first time from the northeast region of Brazil.

Material and methods
Ultraviolet light alcohol pan traps, UV lights placed in front of a white bed sheet, and Malaise traps were used to collect adults (Calor andMariano 2012, Blahnik and. Specimens collected by Malaise and pan traps were preserved in 80% ethanol. Other specimens were collected using ethyl acetate kill jars and pinned. Genitalia were cleared in lactic acid following Blahnik et al. (2007) or in a heated solution of 10% KOH . Prepared genitalia were transferred to micro vials with glycerin and examined with optical microscopy at 40-400 × magnification. Structures were traced in pencil with the use of a camera lucida (drawing tube) mounted on a microscope. Digitally scanned pencil sketches were used as a template and rendered in Adobe Illustrator® CS5. Morphological terminology follows that established by Blahnik (1997).
We also corrected an error in the coding of character 36 from Blahnik (1997) (female genitalia: sternum IX) of the species Chimarra camura that was modified from state "0" (not sclerously fused to segment VIII) to "2" (sclerously fused to segment VIII, broadly fused at base). As previously coded the state "0" for this species contradicted Blahnik's (1997) description and illustrations. In addition, species or life stages were added to the matrix (male and female of Chimarra curvipenis and Chimarra latiforceps and the female of Chimarra camella). The matrix can be found in the Suppl. material 1.
The matrix was rebuilt using Nexus Data Editor (NDE), version 5.0 (Page 2001). The phylogenetic analysis was carried out in Tree analysis using New Technology (TNT), version 1.1 (Goloboff et al. 2008). For the TNT Maximum Parsimony analysis, an exhaustive search was used (implicit enumeration option). Chimarrhodella ulmeri was designed outgroup species. Characters 32, 33 and 36 were ordered, all other characters were unordered. All character were unweighted. Bootstrap analysis was implemented based on a thousand replicate samples.
Types and additional material are deposited in the Museu de Zoologia, Universidade de São Paulo, São Paulo State, Brazil (MZSP), Museu de Zoologia da Universidade Federal da Bahia, Bahia State, Brazil (UFBA, Collection of Aquatic Insects), and University of Minnesota Insect Collection, Minnesota, USA (UMSP), as indicated in the species descriptions. New records are indicated with bold type in the Distribution section.

Results
The analysis resulted in a single parsimonious tree with a tree length of 75, consistency index of 0.640, rescaled consistency index of 0.854, retention index of 0.546, and homoplasy index of 0.360. The tree is presented in Fig. 1, with the synapomorphies and autapomorphies presented below the respective nodes. Bootstrap support values higher or equal to 50% are indicated above the respective nodes. The tree largely reflected the topology presented by Blahnik (1997) with additional characters solving the clade (C. majuscula (C. anticheira, C. latiforceps) C. heligma, (C. camura, (C. curvipenis, C. camella))) but with low support (<50%). There was a reduction of the previous support value (61%) of the clade (C. tortuosa, C. kontilos) because of the similarities of the inferior appendage of C. kontilos, C. heligma and C. curvipenis (character 41). Phylogenetic results concerning the new species are discussed under Remarks.

Chimarra (Chimarrita) rosalesi Group
Synapomorphies recognized for this species group, both in the female genitalia are: segment VIII greatly reduced and membranous dorsally, and sternum IX not fused ventrally to segment VIII (Blahnik 1997). Similarities among males of the group are: anteroventral margin of segment IX elongate, usually tapering to acute apex, sometimes abruptly narrowed preapically; preanal appendages usually basally fused, sometimes flattened and button-like; and phallic apparatus with spines (1 or more) usually short, curved and emerging more apically (Blahnik 1997). Currently, the C. rosalesi Group comprises 7 species. The 6 previously described species are all distributed in the Amazon basin: C. chela, C. neblina (Venezuela and Amazonas states of Brazil), C. forcipata, C. pusilla, C. rosalesi (Venezuela), and C. prolata (Ecuador). Chimarra mesodonta sp. n. unlike the others was recorded from outlying fragment of the Atlantic Forest, Bahia State, Brazil. Diagnosis. According to the phylogenetic analysis, C. mesodonta has a sister relationship with the clade (C. chela (C. pusilla, C. forcipata)) based on the presence of short phallic spines with a pronounced helical twist, but differs from these species by not sharing the flattened and button like preanal appendages. Among the species contained in this clade, this new species most closely resembles C. forcipata by the overall aspect mainly in lateral view, and by both possess a mesally a mesally directed acute projection on the inferior appendage. Chimarra mesodonta can be distinguished from C. forcipata by the following characters: R1 of the hind wing is not fused to the subcosta (fused in C. forcipata); tergum X is shorter, and in lateral view slightly longer than the dorsal portion of segment IX (nearly 2× longer than segment IX in C. forcipata); preanal appendage is not flattened (flattened in C. forcipata); the ventral process is not strongly tapered, having apex subacute to truncate (strongly tapered and acute in C. forcipata); in ventral view the apex of inferior appendage is broad and a projection is formed in the medial margin (apex strongly narrowed and with the projection formed apically in C. forcipata); and the phallus bears 2 large helically curved spines (several small spines in C. forcipata).
Male genitalia. Segment IX synsclerous; lateral view, anteroventral margin expanded, apex narrowed, acute; ventral process elongate, narrow, subacute, somewhat curved. Tergum X short, fused to segment IX; with short weakly sclerotized mesal lobe apically excavated, tergum X fully divided dorsally, separated ventrally until the length of mesal lobe, forming 2 separate, simple, lateral lobes with numerous sensilla. Preanal appendage very short, rounded, button-like, fused near base of tergum X. Inferior appendage short, triangular in lateral aspect; in ventral view, strongly rounded basally, tapered apically, apex rounded, medial margin forming tooth-like projection. Phallotheca tubular, slightly bent at middle, with rounded phallobase; with internal membranous structures and bearing 2 distinct curved phallic spines. Phallotremal sclerite complex could not be distinguished.
Female genitalia. Sternum VII without ventral process. Segment VIII synsclerous, triangular in lateral aspect, dorsally membranous, very reduced; lateral suture line not evident, only demarcated by difference in texture and pigmentation of ventral portion, more granulous; anteroventral margin with subacute, deflected ventral process, posteroventral margin also with short ventral process. Sternum IX elongate, lightly sclerotized basally, with elongate, narrow, paired, ventral sclerites; sternum membranous between paired sclerites, and laterally from base to apex. Tergum IX elongate, narrow, nearly straight, sparsely setose, anteroventrally with short apodeme. Segment X with elongate basal portion, furrowed dorsally, with basal and inner margins more sclerotized, apically with small setose lobes, each with apical cercus. Vaginal apparatus largely membranous, anteriorly with weakly sclerotized structure.
Holotype, male (   Etymology. The species name is derived from the Greek meso, middle, and donti, tooth, referring to the median tooth present in the inferior appendages. Remarks. The aperture between the lateral lobes of tergum X can be wider depending on the specimen examined. Also, membranous structures of the endotheca and the lightly sclerotized mesal lobe of tergum X vary in shape depending on the preparation. When cleared in lactic acid, the basal portion of the endotheca shows some sclerotization and may be considered a rod of the phallotremal sclerite complex. Concerning the phylogenetic relationships, the new species shares character 30(1), segment VIII of female genitalia much narrowed or obsolete dorsally, with the C. rosalesi Group sensu Blahnik (1997). The shared character 7(1), phallic spines short, with pronounced helical twist, supports the clade (Chimarra mesodonta (C. chela (C. pusilla, C. forcipata))). However, the new species does not posses character 13(1), preanal appendages flattened and button-like, a character shared by the other three species.

Chimarra (Chimarrita) simpliciforma Group
Species belonging to this group are recognized by the presence of a single and elongate spine that emerges from the base of phallotheca. Females in the group have reduced or absent apodemes in tergum IX and sternum IX sclerously fused to segment VIII (Blahnik 1997). The C. simpliciforma Group currently contains 12 species, with 11 previously described species distributed through the Amazon Region: C. akantha, C. tortuosa (Amazonas State of Brazil), C. simpliciforma (Amazonas State of Brazil, Guyana, Surinam, and Venezuela), C. xingu (Pará State of Brazil), C. heppneri (Peru); and through Southeastern Brazil: C. camella (Minas Gerais, Rio de Janeiro and São Paulo States) C. camura, C. majuscula (Rio de Janeiro and São Paulo states), C. curvipenis, C. heligma (Minas Gerais), C. kontilos (Bahia, Espírito Santo, Minas Gerais, Rio de Janeiro and São Paulo states), C. latiforceps (Minas Gerais and São Paulo states).
Diagnosis. This species is very similar to Chimarra latiforceps Blahnik & Holzenthal, 2012, mainly by the general shape of tergum X that form apically clavate lobes. Chimarra anticheira can be distinguished from C. latiforceps by the presence of a dorsally directed apical thumb-like projection on the inferior appendage (absent in C. latiforceps). Additionally, the posterolateral margin of tergum IX is more angulate and the tergum X slightly shorter than in C. latiforceps. The phallotheca in C. anticheira is less curved than C. latiforceps and the apicoventral portion of the phallotheca is rounded in C. anticheira, whereas it is excavated in C. latiforceps, also the apex of the phallic spine is angularly truncate (tapered in C. latiforceps).
Male genitalia. Tergum VIII short, forming sclerotized strip over segment IX. Segment IX synsclerous, anterodorsal margin excavate, rounded, posterolateral margin angularly projecting at level of inferior appendages, tapering to pointed apex; anteroventral margin expanded, with apex rounded in ventral aspect; ventral process elongate, narrow, acute, almost straight. Tergum X short, fused to segment IX, in dorsal view with apex mesally divided by rounded excision, extending about half of tergum length, forming paired lobes apically; apical lobes and lateral margins of tergum with many sensilla. Preanal appendage small, rounded, knob-like, positioned close to base of tergum X. Inferior appendage elongate, linear in lateral view, apex with thumb-like dorsally directed projection; in ventral view, appendages mesally curved, with submedial projection on mesal surface. Phallotheca tubular, with rounded phallobase; phallic  spine single, elongate, emerging near phallobase, apparently fused with ventral portion of phallotheca, apex ventrally projecting, angularly truncate, pointed; endotheca forming sheath on basal half. Phallotremal sclerite complex appearing very narrow, elongate, apparently bifid sclerotized rod.
Female genitalia. Sternum VII with ventral process; process large, projecting, subacute, emerging close to middle of segment in lateral aspect. Segment VII synsclerous, short dorsally, anterolateral margin rounded, excavated dorsally and ventrally; segment fused ventrally to sternum IX; anteroventral margin of segment, as viewed ventrally, with short, narrow mesal emargination, margins of emargination distinctly sclerotized; segment bearing dorsal and ventral rounded unpigmented regions, usually around the larger setae. Sternum IX elongate, with paired, angular projections continuous posteriorly with elongate, narrow ventral sclerites; sternum membranous ventrally between the sclerites, and laterally from base until the apex. Tergum IX elongate, narrow, slightly curved, moderately setose, anteroventrally with short apodeme. Segment X with elongate basal portion, furrowed dorsally, with mesal tract of setae in furrow; apically with pair of small, rounded, setose lobes, each with short apical cercus. Vaginal apparatus largely membranous, with anterior sclerite forming ring and with pair of more elongate sclerites posteriorly.
Holotype Etymology. The species name derives from the Greek word anticheira, which means thumb, referring to the diagnostic thumb-like projection present on the inferior appendages.
Remarks. Intra-specific variation may be observed in several structures. In some individuals the mesally formed projection on the inferior appendage is more prominent and there may also be a second subapical smaller projection. Membranous structures of the endotheca can vary in shape depending upon the preparation and some convoluted parts of phallic spines may be difficult to discern. The phylogenetic analysis resulted in a clade (C. majuscula (C. anticheira, C. latiforceps)) based on the shared character 37(1), lobes of tergum X roundly inflated apicaly, club-shaped, and C. anticheira as sister taxon of C. latiforceps based on the characters 36(2), female genitalia with stemum IX sclerously fused to segment VIII, broadly fused at base, and 38(1), male genitalia with ventral margin of tergum X with a small projection subapically. Observed intraspecific variation. In his redescription, Flint (1998) analyzed specimens from diverse localities (Santa Catarina, Rio de Janeiro, São Paulo and also Bahia states) reporting wide variations, mainly in the shape and size of the inferior appendages. For the variant from Bahia, Flint (1998) the described inferior appendages and ventral process as longer, and tergum VII and tergum X as slightly bifid, but he did not provide any illustrations of this variant. Analysis of material from Bahia from the same locality reported by Flint and from other localities revealed other variations: Segment IX is opened dorsally forming a U-shape; in lateral aspect, the posterolateral margin of segment IX is slightly projected at level of inferior appendage. Tergum X in addition to being bifid is also constricted near the base, forming 2 small lateral lobes; the preanal appendages are elongated and tapered, with a small ventral projection; and the inferior appendages are rounded in ventral aspect, and have a medial and apical point on the lateral margin visible in lateral aspect.