Five new species of Alisotrichia Flint, 1964 (Trichoptera: Hydroptilidae: Leucotrichiinae) from Northeastern Brazil

Five new species of Alisotrichia Flint, 1964 microcaddisflies are described and illustrated from type material collected in Northeastern Brazil, constituting the first records of the genus to this region, as it was previously known only from Southeastern and Northern Brazil. The number of Brazilian species of Alisotrichia is doubled herein from five to ten, however, likely there are still many other species to be described. The new species described here are all placed in the orophila species group: A. froehlichi sp. nov. (Sergipe State), A. calori sp. nov. (Bahia and Paraíba states), A. penispinata sp. nov. (Ceará and Pernambuco states), A. dilatata sp. nov. (Ceará and Mato Grosso do Sul states), and A. nordestina sp. nov. (Ceará and Sergipe states). These new species are separated mainly by features of male genitalia, particularly the dorsal area of segment X, the shape of the segment VIII, and the phallus morphology. Currently, the orophila species group is composed by 37 species, more than half of the species diversity of Alisotrichia.


Introduction
Hydroptilidae constitute the most species rich family of caddisflies, with approximately 2,600 species distributed in six subfamilies and 76 genera (Thomson, 2023).Leucotrichiinae are restricted to the New World, but mostly Neotropical and divided into two tribes: Leucotrichiini and The Northeast Region of Brazil is a formal administrative region, with about 20% of the Brazilian territory and encompass nine states.To date, 207 species of Trichoptera are recorded from states in this region (Santos et al., 2023), corresponding to 23% of the Brazilian fauna.This region also houses 54 species of Hydroptilidae (Santos et al., 2023) and, although no nominal species of Alisotrichia has been described from this region, three undescribed species were listed in a survey carried out in the Caatinga biome (Takiya et al., 2016).In the present paper, five new species of Alisotrichia are described and illustrated from male specimens collected at different localities in Northeastern Brazil (Fig. 1).

Material and methods
Specimens were collected at different localities in Alagoas, Bahia, Ceará, Paraíba, Pernambuco, and Sergipe states, Brazil (Fig. 1).Collecting techniques included collapsible light traps (Nessimian et al., in press) and light pan traps (Calor and Mariano, 2012), as well as Malaise traps (Gressitt and Gressitt, 1962).Specimens were preserved in 80% ethanol.To observe and to illustrate genital structures, male abdomens were removed and clarified using warmed solution of 10% KOH (Ross, 1944).After clarification, the abdomen of holotypes was placed in glycerin jelly, mounted on a temporary slide, and then observed under a compound microscope LEICA DM 4000 B LED equipped with digital camera LEICA DMC 2900.Photographs at different focal planes were taken and stacked with CombineZP Image Stacking Software (Hadley, 2010) to be illustrated into an Adobe Illustrator® CC v. 22.0.1 (Adobe Inc.) document.After observation, abdomens were returned to alcohol and stored with the specimen body.Maps were made with QGIS v. 3.10.8(QGIS Development Team, 2020) using Brazilian biome shape layers (IBGE, 2019).Species description was made using the software DELTA (Description Language for Taxonomy) (Dallwitz et al., 1999).Terminology used in descriptions follow mainly that of Marshall (1979) and Harris and Flint (2002).
Abdominal segment VII with ventromesal process, bifurcate in lateral view, with dorsal branch longer than ventral (Fig. 3C).
Male genitalia.Segment VIII with a pair of dorsolateral processes, posterad directed, each bearing a very long, spine-like seta, extending beyond segment apex (Figs.3A, 3C); in lateral view, with rounded apex (Fig. 3C); in ventral view, posterior margin with a very deep mesal Y-shaped incision, with a pair of short, acute processes directed inwards, and a pair of shallow lateral V-shaped incisions (Fig. 3B).Segment IX fused with segment X, reduced ventrally; with a pair of slender, lateral elongate processes, slightly curved inwards in dorsal view (Fig. 3A); anterolateral margins with a pair of slender apodemes reaching segment VII internally (Figs.3A-3C).Segment X long, membranous; with lateral margins slightly arched in dorsal view (Fig. 3A); dorsally with a pair of slender sclerites, each one thinner at midlength, tapering to a rounded apex (Fig. 3A).Subgenital plate, in ventral view, long, extending beyond half length of segment VIII; with anterior portion projecting into a pair of rods; posterior margin subquadrate, with a subapical circular open area (Fig. 3B).Inferior appendages absent.Phallus tubular, constricted mesally; superior portion with basal and median third shovel-like, slightly sclerotized; apical third membranous and apically rounded (Fig. 3D); ejaculatory duct protruding subapically, in an inverted funnel-like portion (Fig. 3D).
Taxonomic notes.This new species is placed in the orophila species group by having a pair of dorsolateral processes on segment VIII.Alisotrichia froehlichi sp.nov. is most similar to A. kanukua Harris & Flint, 2002 and A. dilatata sp.nov.because they share the segment X, in dorsal view, with arched lateral margins and apex slightly concave, and segment VIII, in lateral view, with rounded apex, and in ventral view, with a mesal Y-shaped incision and paired lateral V-shaped incisions.However, A. froehlichi sp.nov.can be distinguished by the presence of the ventromesal process on abdominal segment VII, and by the posterior margin of the segment VIII, in ventral view, with a pair of short acute processes, directed inwards, arising at the edge of the mesal incision (Fig. 3B).In addition, the posterior margin of segment VIII, in ventral view, also bears shallow lateral incisions, but in this new species they are shallower than in others (Fig. 3B).The general aspect of the phallus is also diagnostic, with basal and sclerotized portion resembling a shovel and apical region mostly membranous (Fig. 3D).
Male genitalia.Segment VIII with a pair of dorsolateral processes, directed anterad, with apex curved posterad, each one bearing an elongate, spine-like seta, extending beyond segment apex (Figs.5A, 5C); in lateral view, with bifid apex, dorsal portion rounded, ventral portion acute (Fig. 5C); in ventral view, posterior margin with a deep mesal Y-shaped incision, laterally to mesal incision paired lobes with a digitate process internally, and outerad of lobes paired narrow U-shaped incisions (Fig. 5B).Segment IX fused with segment X, reduced ventrally; with a pair of slender, lateral elongate processes, slightly curved inwardly in dorsal view (Fig. 5A); anterolateral margins with a pair of slender apodemes reaching segment VI internally (Figs.5A-5C).Segment X long, membranous, slightly elliptical in dorsal view (Fig. 5A); dorsally with a pair of sclerites shaped like a leg on tiptoe, with a constriction followed by a subbasal dilatation, tapering to an acute basis, apex rounded (Fig. 5A).Subgenital plate, in ventral view long, reaching segment VII internally; anterior portion projecting into a pair of rectangular rods; posterior margin rounded, with a wide subapical open area (Fig. 5B).Inferior appendages absent.Phallus tubular, long, mesolaterally with four digitate sclerites grouped at each side of phallus, at midlength, sclerites partially overlapping (Fig. 5D); with a pair of apical lobes, each tapering to a rounded apex, directed inwardly, with internal margins sclerotized (Fig. 5D); ejaculatory duct projecting between apical lobes (Fig. 5D).
Taxonomic notes.Alisotrichia calori sp.nov.belongs to the orophila group because of the presence of dorsolateral processes on segment VIII (Fig. 5A).This new species is very distinctive, but in some respects resembles the previous one, A. froehlichi sp.nov., and A. dilatata sp.nov., mainly because of the deep Y-shaped and the lateral pair of incisions on posterior margin of segment VIII in ventral view (Fig. 5B).Alisotrichia calori sp.nov.can be easily distinguished from these by: (1) the shape of the dorsal sclerite on segment X, which resembles a leg on tiptoe; (2) the mesal Y-shaped incision on posterior margin of segment VIII in ventral view, delimited by paired lateral rounded lobes, each with a very small digitate process internally (Fig. 5B); and (3) the shape of the phallus, with lateral digitate sclerites grouped laterally at midlength (Fig. 5D).
Etymology: This species is named in honor of Dr. Adolfo Calor, Brazilian entomologist and former student of Dr. Claudio Froehlich, in recognition of his contributions to the study of the neotropical caddisflies and for providing material used in this work.
Male genitalia.Segment VIII with a pair of dorsolateral processes, posterad directed, each bearing an elongate, spine-like seta, slightly surpassing the segment apex (Figs.7A, 7C); in lateral view, with apical portion tapering abruptly to an acute apex (Fig. 7C); in ventral view, posterior margin with a deep mesal wide incision, with serrated, sclerotized inner margins, bearing a pair of pointed sclerotized processes at midlenght, with a small, mesal bifid projection (Fig. 7B); mesal incision with margins produced inwardly, in lateral view, forming a sclerotized Y-shaped structure (Fig. 7C).Segment IX fused with segment X, reduced ventrally; with a pair of lateral slender, elongate processes, curved downwards in lateral view, curved inwardly in dorsal view (Figs.7A, 7C); anterolateral margins with a pair of slender apodemes reaching segment VI internally (Figs.7A-7C); ventrally with an arch-like apodeme (Fig. 7B).Segment X long, membranous; apical portion slightly dilated; apex with with U-shaped mesal incision (Fig. 7A); dorsally with a pair of slender, sinuous sclerites, with basal region acute, median region slightly constricted, and apical region slightly dilated and rounded (Fig. 7A).Subgenital plate inverted, with basal portion directed posterad, apical portion directed anterad and partially folded under itself, not visible externally.Inferior appendages absent.Phallus tubular, long, constricted at basal third; mesoapically enlarged, with margins sclerotized; apically constricted, with a pair of sclerotized, smaller anterior spine-like processes, and a pair of sclerotized, larger posterior spine-like processes; laterally with paired lobes, each with lateral margins bordered by numerous small spines, superior and inner margins of lobes with numerous larger spines, posteriorly with a pair of straight, knife-like, sclerotized processes, and a pair of inwardly curved, sclerotized processes, with apices crossing the other (Fig. 7D); ejaculatory duct protruding subapically, in an inverted funnel-like portion (Fig. 7D).
Taxonomic notes.Alisotrichia penispinata sp.nov.belongs to the orophila group by having a pair of dorsolateral processes on segment VIII each bearing a long and spine-like setae.This new species is very similar to A. nessimiani Santos, 2011 due to the general aspect of the male genitalia structures, mainly the segment IX.However, A. penispinata sp.nov.can be distinguished from A. nessimiani and other species in the genus by the shape of the phallus apex, particularly because of the more conspicuous processes.In the new species, the pair of lateral processes on phallus apex is lobate and bordered by many small spines (Fig. 7D), whereas in A. nessimiani it is more triangular with serrate margins.In addition, in A. nessimiani the posterior margin of the segment X is almost straight, while in A. penispinata sp.nov. it is concave.Moreover, the Y-shaped sclerotized structure ventroapically at the lateral side of segment VIII (Fig. 7C) helps to distinguish this new species.
The subgenital plate of the holotype of A. penispinata sp.nov. is completely internalized and inverted, with its apex directed anterad and folded under itself.In some specimens, this structure was even more folded, resembling the "spring-like process" (Harris and Flint, 2002) described for A. circinata Flint, 1992, A. panamensis Harris & Flint, 2002, A. muellita Harris & Flint, 2002, and A. woldai Harris & Flint, 2002, or the "spiral process" (Angrisano and Sganga, 2009) decribed for A. cainguas Angrisano & Sganga, 2009.Due to the position in which they are found, and their similar shape, probably these structures are the same, corresponding to the apical portion of the subgenital plate.Etymology: This species is named in reference to the small spines on lateral lobes of phallus apex, from Latin: "penis" (penis, phallus) and "spina" (spine).
Male genitalia.Segment VIII with a pair of dorsolateral processes, posterad directed, each bearing an elongate, spine-like seta, extending beyond segment apex (Figs.9A, 9C); in lateral view, with rounded apex (Fig. 9C); in ventral view, posterior margin with a deep mesal Y-shaped and lateral narrow V-shaped incisions (Fig. 9B).Segment IX fused with segment X, reduced ventrally; with a pair of lateral slender, elongate processes, slightly curved upwards in lateral view, slightly curved inwardly in dorsal view (Fig. 9A); anterolateral margins with a pair of slender apodemes reaching segment V internally (Figs.9A-9C).Segment X long, membranous; with lateral margins slightly arched in dorsal view, with apex slightly concave (Fig. 9A); dorsally with a pair of slender, sinuous sclerites, tapering to acute apices (Fig. 9A).Subgenital plate, in ventral view, long, reaching segment VII internally, with anterior portion produced into a pair of rods; posterior margin subrectangular, with a small subapical open area (Fig. 9B).Inferior appendages absent.Phallus tubular, long, with a mesal constriction followed by a dilatation, subapically constricted and covered by a very thin membrane; with a pair of apical lobes, each one with bifid apex, internally flattened and with a pointed projection.(Fig. 9D); ejaculatory duct projecting between apical lobes (Fig. 9D).
Taxonomic notes.This new species also belongs to the orophila group due to the presence of a pair of dorsolateral processes on segment VIII.Alisotrichia dilatata sp.nov. is more similar to A. kanukua Harris & Flint, 2002 and A. froehlichi sp.nov.by the segment X having slightly arched lateral margins, with slender sclerites, and segment VIII with rounded apex in lateral view and posterior margin bearing a median Y-shaped and a pair of V-shaped lateral incisions in ventral view.This new species can be distinguished from this and other Alisotrichia species by: (1) the dorsal sclerites on segment X sinuous (Fig. 9A); (2) the deeper mesal Y-shaped and a pair of shallow lateral V-shaped incisions on posterior margin of segment VIII in ventral view (Fig. 9B); and (3) the pair of long, slender, lateral processes of segment IX (Fig. 9E).Furthermore, in A. dilatata sp.nov. the phallus aspect is peculiar, with apical portion almost elliptical in dorsal view, and the pair of bifid apical lobes are flattened apically and produced into a pointed projection (Fig. 9D).
Etymology: The species name is a reference to the apical portion of the phallus being expanded or dilated, from Latin, "dilatata" (expanded).
Male genitalia.Segment VIII with a pair of dorsolateral processes, directed posterad, each bearing an elongate, spine-like seta, extending beyond segment apex (Figs.11A, 11C); with a subapical constriction, posterior margin with a pair of lateral acute sclerotized processes, directed posterad, in lateral view (Fig. 11C); in ventral view, mesally with a pair of short and rounded lobes, separated by a shallow incision, lateral acute sclerotized processes slightly curved inwardly (Fig. 11B).Segment IX fused with segment X, reduced ventrally; with a pair of lateral elongate processes, curved downwards in lateral view; slightly curved inwards in dorsal view (Figs.11A, 11C); anterolateral margin with a pair of slender apodemes reaching segment VII internally (Fig. 11A-11C).Segment X long, membranous, almost rectangular in dorsal view (Fig. 11A); dorsally with a pair of slender sclerites, with rounded and divergent apices (Fig. 11A).
Subgenital plate, in ventral view, short, not extending beyond half length of segment VIII; anterior portion projecting into a pair of rods; posterior portion trapezoidal (Fig. 11B).Inferior appendages absent.Phallus tubular and short, constricted mesally; with a pair of apical capitate lobes, each one with internal margin concave, pointed projection at midlenght, and a rod-like projection at base (Fig. 11D); apical portion covered by a thin, quadrangular membrane (Fig. 11D); ejaculatory duct projecting between apical lobes (Fig. 11D).
Taxonomic notes.This new species has a pair of dorsolateral processes on segment VIII, thus, is placed in the orophila group.Alisotrichia nordestina sp.nov. is very distinctive and somewhat resembles A. macae Santos, 2011, A. mathisi Harris & Flint, 2002, and A. paxilla Harris & Flint, 2002, particularly because of the pointed, sclerotized posterolateral processes on segment VIII (Fig. 11A-11C).However, the new species is readily distinguished from these other species by the shallow mesal incision on posterior margin of segment VIII in ventral view, forming a pair of short and rounded lobes (Fig. 11B); and by the shape of the phallus apex, with a pair of capitate lobes, each one with the internal margin concave, a pointed projection, and an additional rod-like projection at base (Fig. 11D).Etymology: "Nordestina", a Portuguese adjective, is the gentilic for those born in Northeast Region of Brazil and refers to the localities where specimens of this species have been collected.

Discussion
The first record of a Hydroptilidae species from Northeastern Brazil occurred only ten years ago (Souza et al., 2013), as a reflection of Wallacean and Linnean shortfalls (Hortal et al., 2015).Currently, with the species described in this work, the number of species in this region reached 58 but, of the nine states of the Northeastern Region, four have less than 10 species recorded: Maranhão, Paraíba, Sergipe, and Rio Grande do Norte, with the latter having no recorded species (Santos et al., 2023).This indicates that probably there are still many other species to be described and recorded from Northeastern states.
The Caatinga biome, along with the Chaco and Cerrado biomes, is part of the South American dry diagonal, an arid corridor that separates the Amazon and the Atlantic rainforests (Ab'Saber, 1977).Most of the Northeast Region of Brazil is occupied by the Caatinga, which is characterized by the absence of rain for long periods and high average annual temperature (Prado, 2003).Despite this, Alisotrichia species described seems to be typical of humid forests, and even those from Ceará and Paraíba states, within the Caatinga area, are in fact from humid forest.Localities in these two states with Alisotrichia species described here (in Bananeiras and Ubajara municipalities) are known as "brejos de altitude"."Brejos de altitude" are humid forest enclaves within the Caatinga area and likely represent past connections between the Amazon and Atlantic forests (Ledo and Colli, 2017).
Presently, the orophila species group is composed by 37 species, more than half of the species diversity of Alisotrichia.Harris and Holzenthal (1993) recovered this species group as monophyletic and, apparently, there was a large diversification of this lineage in South America.Of the 25 species of Alisotrichia known from South America, 14 are in the orophila species group, including the new species described here.However, biogeographical studies are needed to indicate historical processes that led to this distribution.

Conclusions
The genus Alisotrichia now has 67 species, ten of which are recorded for Brazil.The new data presented herein indicate that the microcaddisfly fauna is still very underexplored.Groups that were not extensively studied, such as Alisotrichia, and localities poorly sampled, such as in Northeastern Brazil, probably will reveal a high number of new species.

Figure 1
Figure 1 Localities in Northeastern Brazil (yellow in top right map) where type specimens of the new Alisotrichia species were collected.