The genus Trichorhina Budde-Lund in Brazil , with description of seven new species ( Isopoda , Oniscidea , Platyarthridae )

1. Laboratório de Carcinicultura, Instituto Superior de Ciências Biomédicas, Universidade Estadual do Ceará, Campus do Itaperi, Av. Paranjana, 1700, 60740-903, Fortaleza, Ceará, Brasil. (leilasouza5000@gmail.com.br) 2. Programa de Pós-Graduação em Ciências Biológicas (Zoologia), Departamento de Sistemática e Ecologia, Centro de Ciências Exatas e da Natureza, Universidade Federal da Paraíba, 58059-900, João Pessoa, Paraíba, Brasil. (joafrancio@gmail.com) 3. Programa de Pós-Graduação em Biologia Animal, Departamento de Zoologia, Instituto de Biociências, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves, 9500, prédio 43435, 91501-970, Porto Alegre, Rio Grande do Sul, Brasil. (ivanklin.filho@gmail.com)

leiStikow & wägele (1999) included Trichorhina pearsei (Creaser, 1938) from Mexico as occurring in Brazil.Perhaps this was a misinterpretation of Souzakury (1993), because its eyes could be compared with those of the species described therein and to comments on its synonymy.
The number of ommatidia forming the eye is used here as a primary diagnostic feature.It appears that there is a general trend in eye reduction (making part of a regressive evolution also evident in the reduction of body pigmentation) in many species of Trichorhina, not necessarily related to environment but more generally to an endogeous lifestyle.
There are numerous specimens of anophtalmous Trichorhina not yet studied and deposited at Museu Nacional do Rio de Janeiro, along with many specimens collected in caves from the Brazilian states of Bahia, Minas Gerais, Paraná, and São Paulo that are temporarily being kept in Universidade Estadual do Ceará (UECE) for further investigation.

MATERIAL AND METHODS
Type specimens are deposited in the Museu Nacional, Universidade Federal do Rio de Janeiro (MNRJ), Rio de Janeiro, Brazil.The material examined of Trichorhina acuta is deposited in the collection of Oniscidea at Universidade Estadual do Ceará, Fortaleza, Brazil (UECE).
ABSTRACT.Seven new species of Trichorhina Budde-Lund, 1908 are described, six from Southeastern Brazil, T. biumbonata sp.nov., T. lenkoi sp.nov., T. myrmecophila sp.nov., T. orensis sp.nov., T. sexdens sp.nov., T. tropidocerata sp.nov., and one from Central Brazil, T. crassisetae sp.nov.An emended diagnosis for the genus and a key to the 19 species recorded from Brazil are provided.Trichorhina acuta Araújo & Buckup, 1994 is recorded to state of Mato Grosso do Sul.
Five new species possess between four to six ommatidia and they may be compared to species which also possess a similar number of ommatidia.The other new taxa of Trichorhina, even though they possess between four and six ommatidia, could be considered unrelated with the new ones because of other unique features.
The structures to which we here refer as "rods" have been called by Vandel (1952) "fins bâtonnets cilindriques".Graphics illustrating relative position of noduli laterales are used according to Vandel (1962).Measurements refer to maximum values.
Distribution.Trichorhina is cosmopolitan.There is a total of 56 species, of which about 30 occur in the Neotropical Region (SchmalfuSS, 2003).There are 12 species hitherto recorded in Brazil, which added to the seven new species herein described, give a total of 64 species for the world (see Table I).
Remarks.Species of Trichorhina are mostly tropical.It is probably an artificial assemblage (e.g. taiti & ferrara, 1987).According to the current knowledge, there is a high degree of endemism for the majority of species but there are a few widespread species, such as T. tomentosa (Budde-Lund, 1893) and T. heterophthalma Lemos de Castro, 1964 which probably were dispersed by man.
Trichorhina dobrogica Radu, 1960 from Romania.It may be distinguished from the Brazilian species by the transverse lines on pereonites I-VI, and a distal joint of antennula with nine aesthetascs (five or six in Brazilian species).
Trichorhina giannelli Arcangeli, 1929 from the Antilles and Central America.Distinguished from the new Brazilian species by the longitudinal ridges on the mesepistome.
Trichorhina guanophila Souza-Kury, 1993 from Brazil.This species belongs to the group of species characterized by a double pair of noduli laterales on pereonite VII.
Trichorhina micros from Mauritius and Trichorhina minutissima from Cargados (Indian Ocean).These taxa belong to the group of species characterized by serrate teeth on the outer ramus of the maxillulae and by a double row of noduli laterales per side (taiti & ferrara, 1987).
Trichorhina minima Schmalfuss & Ferrara, 1978 from Togo.It is distinguished from Brazilian species by the bulbous profrons.
Trichorhina quisquiliarum (Budde-Lund, 1893) from Venezuela.It is distinguished from new Brazilian species by the uneven pigmentation of ommatidia, four unpigmented and two dark colored.
Trichorhina tatianae Araújo & Almerão, 2007 from Brazil.It is distinguished from the new Brazilian species by the pronounced lateral projection on male pereopod VII ischium.
Besides these nine species, there are ten others with four to six ommatidia, whose differences are cited separately under the diagnosis of each new species.Description.Pigmentation of body faint, pale yellow, head with small brown spots.Eyes dark brown with five ommatidia (Fig. 10).Pereonite I with anterior margins reaching the eyes (Fig. 8).Cephalic lateral lobes small, shorter than median lobe which has rounded apex and straight sides (Fig. 9).Pleon slightly narrower than pereon.Pereon, pleon and telson densely provided with fan-shaped scale-setae (Fig. 15).In the posterior margins of pereonites these fan-shaped scale-setae are large and wide, alternating with small and narrow ones, and in the lateral margins they are small.Both median axes of fan-shaped scale-setae evident, as well as the secondary supporting axioles.Noduli laterales with featureless base.Pereonite VII with only one nodulus lateralis on each side.Position of noduli laterales as illustrated (Fig. 1).Antennula with distal joint with six to seven aesthetascs (Fig. 11).Second joint of antennal peduncle with longitudinal sinuous crest in outer border, more evident in the female (Fig. 12).Left mandible without rods between molar and incisory processes (Fig. 13).Six to seven penicils in molar process of mandibles (Figs 13,14).Outer group of exite of maxillulae with three teeth and inner group with four undivided teeth (Fig. 16).Maxilla with inner lobe narrower than outer lobe.Sensilla on the inner lobe (Fig. 17).Endite of maxilliped with one small tooth in outer distal border, and with inner distal border smooth (Fig. 18).Pleopods without respiratory areas.
Remarks.Trichorhina biumbonata sp.nov. is distinguished from the species with four to six ommatidia by the antennal crest, and further as follows: from T. acuta by maxillulae with undivided teeth (two bifid in T. acuta).From T. argentina by the exopod of pleopod I of male cordiform (ovoid in T. argentina).From T. australiensis by 1) molar process of mandibles with six to seven penicils (one in T. australiensis); 2) seven undivided teeth in maxillulae (in T. australiensis nine, of which two bifid); 3) endite of maxilliped without tooth in inner distal border; with only one in outer distal border (one tooth in inner distal border; one in distal outer in T. australiensis).From T. barbouri by 1) second joint of antennal flagellum of female without groove; 2) tegument smooth.From T. hospes by maxillulae with seven undivided teeth (in T. hospes nine, two bifid).From T. pallida by 1) molar process of mandibles with five to seven penicils (two in T. pallida); 2) exite of maxillulae with seven undivided teeth (two of inner group bifid in T. pallida).From T. papillosa by 1) absence of papillae on tegument of body; 2) endopods of uropods surpass the tip of telson and of protopods.From T. paraensis by 1) antennula with distal joint with six to seven aesthetascs altogether (five altogether in two groups in T. paraensis); 2) molar process of both mandibles with six to seven penicils (one penicil in T. paraensis).From T. silvestrii by 1) antennula with distal joint with six to seven aesthetascs altogether (four in two groups in T. silvestrii); 2) molar process of both mandibles with six to seven penicils (three in T. silvestrii).From T. vandeli by 1) maxillulae with seven undivided teeth (in T. vandeli eight, two bifid); 2) endite of maxilliped with one tooth in outer distal border (two teeth in T. vandeli).
Etymology.From Latin bi = two + umbo = protuberance, due to the sinuous protuberance forming a crest on the antennal peduncle.Trichorhina crassisetae sp.nov.

Diagnosis. Pigmentation of body dark brown.
Eyes with eight black ommatidia.Peduncle of antenna with conspicuous bristles.Exite of maxillulae with four teeth in the outer group, one very small.Pereopod I of male with setae bifurcated in carpus.Endopod of pleopod I of male with row of small setae in inner border.Measurements.Male, length: 3.18 mm, width: 1.19 mm; female, length: 2.52 mm, width: 1.06 mm.
Description.Pigmentation of body dark brown; lighter in head (with small dark brown spots) (Fig. 25), antennae, sides of pereon and of pleon and uropods.Eyes black with eight ommatidia.Pereonite I with anterior margins reaching the eyes.Cephalic lateral lobes small, shorter than median lobe which has rounded apex and straight sides (Fig. 26).Eyes with eight ommatidia.Pleon outline continuous with pereon; pleonites III-V with well developed epimera.Pereon, pleon and telson covered with fan-shaped scale-setae (Fig. 27).In the posterior margins of pereonites, scalesetae large and wide intercalate with small and narrow, and in the lateral margins small.Fan-shaped scale-setae more or less rounded and with four shafted frame.Noduli laterales with featureless base.Pereonite VII with only one nodulus lateralis on each side.Position of noduli laterales as illustrated (Fig. 2).Distal joint of antennula with five aesthetascs (Fig. 28).Antenna (Fig. 29) stretched reaches posterior margin of pereonite II.Second joint of antennal peduncle without dorsal keel nor crest in outer border.Second joint of antennal flagellum without groove.Left mandible (Fig. 30) without rods between molar and incisory processes.Six penicils in molar process of left mandibles (Fig. 30), right four (Fig. 31).Outer group of exite of maxillulae with four teeth, one much smaller.Inner group of exite of maxillulae with four teeth: two bifid (Fig. 32).Maxilla with inner lobe narrower than outer lobe.Sensilla on the inner lobe (Fig. 33).Endite of maxilliped without small teeth in outer distal border, and with inner distal border smooth (Fig. 34).Pleopods without respiratory areas.
Remarks.Trichorhina crassisetae sp.nov. is distinguished from species with eight to twelve ommatidia as follows: from T. amazonica Souza-Kury, 1997 by 1) molar process of left mandible with six penicils (four in T. amazonica); 2) maxillulae with eight teeth, two bifid (in T. amazonica seven, two bifid).From T. atlasi by 1) absence of frontal line (frontal line very thin in T. atlasi); 2) sexual dimorphism in pereopod I of male: carpus with remarkable bifurcate setae (males without particular features, see Vandel 1959:101, for T. atlasi); 3) pleonites three to five with well developed points (blunt in T. atlasi).From T. kribensis Ferrara & Schmalfuss, 1983 by 1) antenna without aesthetascs; 2) exite of maxillulae with eight teeth, two bifid (nine undivided in T. kribensis); 3) pereopod VII of male without dimorphism.From T. marianii Arcangeli, 1930 by 1) tegument smooth (granulous in T. marianii); 2) sexual dimorphism in pereopod I of male: carpus with bifurcate setae (sexual dimorphism only in length and width of merus and carpus in T. marianii).From T. pubescens (Dollfus, 1893) by 1) antenna with joints of maxillulae with six undivided teeth and one bifid (two of inner group bifid in T. acuta).From T. argentina by 1) antenna shorter; 2) eyes light brown (black in T. argentina); 3) coxal plates without glandular pores.From T. australiensis by 1) exite of maxillulae with six undivided teeth and one bifid (in T. australiensis nine, inner group with all bifid); 2) presence of frontal lobe.From T. barbouri by second joint of antennal flagellum without groove and tegument smooth.From T. biumbonata sp.nov.by 1) second joint of antennal peduncle without crest in outer border; 2) molar process of mandibles with one penicil (five to seven in T. biumbonata).From T. hospes by 1) exite of maxillulae with six undivided teeth and one bifid (in T. hospes nine, two bifid); 2) endite of maxilliped with two teeth in outer distal border (without teeth in T. hospes).From T. pallida by 1) molar process of mandibles with one penicil (two in T. pallida); 2) exite of maxillulae with six undivided teeth and one bifid (two of inner group bifid in T. pallida).From T. papillosa by 1) molar process of mandibles with one penicil (three in T. papillosa); 2) exite of maxillulae with six undivided teeth and one bifid (two bifid in T. papillosa); 3) endite of maxilliped with two teeth in outer distal border and one in inner distal border.From T. paraensis by 1) exite of maxillulae with six undivided teeth and one bifid (in T. paraensis eight, two bifid); 2) endite of maxilliped with two teeth in distal outer border (with one tooth in distal outer border and one tooth in inner border in T. paraensis).From T. silvestrii by 1) molar process of both mandibles with one penicil (with three penicils in T. silvestrii); 2) exite of maxillulae with six undivided teeth and one bifid (in T. silvestrii eight, two bifid).From T. vandeli by 1) antennula with distal joint with about five aesthetascs (with seven to eight aesthetascs in T. vandeli); 2) exite of maxillulae with six undivided teeth and one bifid (in T. vandeli eight, two bifid).
Etymology.Species named after Karol Lenko, who collected the type series, and many other Brazilian Oniscidea.

Diagnosis. Pigmentation of body pale yellow.
Eyes with five black ommatidia.Pleopod I of male with exopod slightly rounded; endopod with apex with row of micro-setae.
Description.Pigmentation of body faint, pale yellow, with small brown spots in head.Eyes black with five ommatidia.Head partly sunken in pereonite II-V of peduncle without inferior groove; 2) exite of maxillulae with eight teeth, of which two bifid (all teeth undivided in T. pubescens).Promptly distinguishable from all other species of the genus by eyes with eight ommatidia.
Etymology.From Latin crassus = thick + seta = bristle, due to the stout bristles in antenna.
Diagnosis.Pigmentation of body brown.Eyes with five ommatidia light brown.Exite of maxillulae with six undivided teeth plus one bifid tooth.
Description.Pigmentation of body brown, with small dark brown spots in head.Eyes light brown with five ommatidia, not contiguous.Pereonite I with anterior margins reaching the eyes.Cephalic lateral lobes small, shorter than median lobe which has apex rounded and straight sides (Fig. 44).Pleon outline continuous with pereon; telson subtriangular with sides slightly convex.Surface with hexagonal plates.Pereon, pleon and telson covered with fan-shaped scale-setae (Fig. 46), with four axial rods.Noduli laterales (Fig. 45) with featureless base.Pereonite VII with only one nodulus lateralis on each side.Position of noduli laterales as illustrated (Fig. 3).Antennula with distal joint with about five aesthetascs.Antenna (Fig. 47) stretched reaches posterior margin of pereonite II.Second joint of antennal peduncle without crest in outer border and without dorsal keel.Second joint of antennal flagellum without groove.Left mandible (Fig. 48) without rods between molar and incisory processes.Number of penicils in molar process of left mandibles one (Fig. 48), right one (Fig. 49).Outer group of exite of maxillulae with three teeth.Inner group of exite of maxillulae with four teeth: one bifid (Fig. 50).Maxilla with inner lobe narrower than outer lobe.Sensilla on the inner lobe.(Fig. 51).Endite of maxilliped with two small teeth in distal outer border, and with inner distal border smooth (Fig. 52).Pleopods without respiratory areas.

Souza et al.
I, anterior margins of pereonite I reaching the eyes.Cephalic lateral lobes slightly ahead of median lobe which has apex rounded and straight sides (Figs 59,60).Pleon slightly narrower than pereon, pleonites III-V with well developed points (Fig. 58).Body surface with hexagonal plates.Pereon, pleon and telson covered with fan-shaped scale-setae bearing two axial rods (Fig. 63).Noduli laterales with featureless base (Fig. 62).Pereonite VII with only one nodulus lateralis on each side.Position of noduli laterales as illustrated (Fig. 4).Antennula with middle joint much smaller than others, distal joint with five aesthetascs (Fig. 61).Antenna (Fig. 64) stretched reaches posterior margin of pereonite II.Second joint of antennal peduncle without crest in outer border and without dorsal keel.Second joint of antennal flagellum with a slightly transversal groove.Left mandible (Fig. 65) without rods between molar and incisory processes.Number of penicils in molar process of left mandibles one (Fig. 65), right one (Fig. 66).Outer group of exite of maxillulae with three teeth.Inner group of exite of maxillulae with four simple teeth (Fig. 67).Maxilla with inner lobe narrower than outer lobe wich is apically truncate.Sensilla on the inner lobe (Fig. 68).Endite of maxilliped with two small teeth in outer distal border, and irregular inner distal border (Fig. 69).Pleopods without respiratory areas.
Male.Pereopods I (Fig. 70) and VII (Fig. 71) without apparent sexual dimorphism (see pereopods I and VII of female in figures 73 and 72, respectively).Carpus of pereopod I of male without bristle field.Pleopod I with exopod rounded (Fig. 74); endopod (Fig. 75) with distal half slightly turned to the outside and apex armed with a short row of micro-setae parallel to the inner border.Pleopod II with triangular exopod (Fig. 77); endopod with distal half gradually tapered (Fig. 76).Pleopod V with sub-rectangular exopod (Fig. 78).
Remarks.Trichorhina myrmecophila sp.nov. is distinguished from other species with eye with four to six ommatidia as follows: from T. acuta by 1) molar process of mandibles with one penicil (six in T. acuta); 2) exite of maxillulae with seven undivided teeth (two of inner group bifid in T. acuta).From T. argentina by 1) exopod of pleopod I of male rounded (ovoid in T. argentina); 2) endopods of uropods relatively longer.From T. australiensis by 1) antennula with joints of different proportions; 2) exite of maxillulae with seven undivided teeth (in T. australiensis nine, five of which bifid); 3) exopod of pleopod I of male rounded (narrowed in inner side in T. australiensis).From T. barbouri by 1) second joint of antennal flagellum without groove and tegument smooth.From T. biumbonata sp.nov.by 1) second joint of antennal peduncle without crest in outer border; 2) molar process of mandibles with one penicil (with about seven in T. biumbonata); 3) endite of maxilliped with two teeth in upper outer margin (one in T. biumbonata); 4) pereopod I of male with setae undivided (with up to four points in T. biumbonata).From T. hospes by 1) antennula with distal joint with five aesthetascs (six in T. hospes); 2) exite of maxillulae with seven undivided teeth (in T. hospes nine, two bifid).From T. lenkoi sp.nov.by 1) pigmentation of body pale yellow (light brown in T. lenkoi); 2) eyes black (light brown in T. lenkoi); 3) pleon slightly narrower than pleon (continuous with pereon in T. lenkoi); 4) endopod of pleopod I of male with row of micro-setae in apex.From T. pallida by 1) molar process of mandibles with one penicil (two in T. pallida); 2) exite of maxillulae with seven undivided teeth (in T. pallida seven, two bifid); 3) exopod of pleopod I of male rounded (elliptic in T. pallida).From T. papillosa by 1) molar process of mandibles with one penicil (three in T. papillosa); 2) exite of maxillulae with seven undivided teeth (in T. papillosa seven, two bifid); 3) endite of maxilliped with two teeth in distal outer border.From T. paraensis by 1) pereon, pleon and telson with fan-shaped scale-setae (with ovoid scale-setae in T. paraensis); 2) endite of maxilliped with two teeth in outer distal border (with one tooth in T. paraensis).From T. silvestrii by 1) distal joint of antennula with five aesthetascs (four in T. silvestrii); 2) exite of maxillulae with seven undivided teeth (in T. silvestrii eight, two bifid).From T. vandeli by 1) distal joint of antennula with five aesthetascs (seven to eight in T. vandeli); 2) molar process of mandibles with one penicil (with a group of many penicils in T. vandeli).
Etymology.Species name stems from Greek and refers to the collecting of the type series in nest of ants.
Remarks.Trichorhina orensis sp.nov. is distinguished from other species with four to six ommatidia, as follows: from T. acuta by molar process of mandibles with one penicil (six in T. acuta).From T. argentina by 1) body unpigmented (purplish uniform pigmentation in T. argentina); 2) brown ommatidia (black in T. argentina); 3) coxal plates without glandular pores.From T. australiensis by exite of maxillulae with seven teeth, of which two bifid (in T. australiensis nine, five bifid), and endite of maxilliped without tooth in distal inner border.From T. barbouri by second joint of antennal flagellum without groove and tegument smooth.From T. biumbonata sp.nov.by 1) second joint of antennal peduncle without crest in outer border; 2) molar process of mandibles with one penicil (with about seven in T. biumbonata); 3) endite of maxilliped with two teeth in distal outer border (one in T. biumbonata).From T. hospes by exite of maxillulae with seven teeth, of which two bifid (in T. hospes nine, two bifid).From T. lenkoi sp.nov.by endite of maxilliped without teeth in inner distal border, and dactylus of pereopod I of male with inner seta larger.From T. myrmecophila sp.nov.by the inner group of exite of maxillulae with two bifid teeth (four undivided teeth in T. myrmecophila), and endopod of pleopod II of male without row of scale-setae.From T. pallida by the molar process of mandibles with one penicil (two in T. pallida), and endopod of pleopod I of male with distal half turned to the outside (straight in T. pallida).From T. papillosa by the molar process of mandibles with one penicil (three in T. papillosa), and endite of maxilliped with two teeth in outer distal border.From T. paraensis by exite of maxillulae with seven teeth, of which two bifid (in T. paraensis eight, two bifid), and endite of maxilliped without teeth in inner distal border (with one tooth in inner distal border in T. paraensis).From T. silvestrii by distal joint of antennula with about eight aesthetascs (four in T. silvestrii), and molar process of mandibles with one penicil (three in T. silvestrii).
From T. vandeli by molar process of mandibles with one penicil (with a group of many penicils in T. vandeli), and exite of maxillulae with seven teeth, of which two bifid (in T. vandeli eight, two bifid).
Etymology.From Latin ora = beach, referring to microhabitat where the individuals were collected.
Description.Body brown, with small dark brown spots in head.Eyes dark brown with four ommatidia.Head narrowed in the anterior half and not sunken in pereonite I. Cephalic lateral lobes very small, shorter than the median lobe, which has rounded apex (Figs 95,96).Body surface with plates.Pereon, pleon and telson covered with fan-shaped scale-setae.Noduli laterales with simple base.Each side of pereonite VII with one nodulus lateralis.Position of noduli laterales as illustrated (Fig. 6).Second joint of antennal peduncle without crest in outer border and without keel in dorsal side.Second joint of antennal flagellum entire (Fig. 97).Left mandible (Fig. 98) without rods between molar and incisory processes.Number of penicils in molar process of left mandibles one (Fig. 98), right one.Outer group of exite of maxillulae with three teeth.Inner group of exite of maxillulae with three undivided teeth (Fig. 99).Endite of maxilliped (Fig. 100) with two small teeth in distal outer border, and one small tooth in distal inner border.Pleopods without respiratory areas.

Trichorhina biumbonata sp. nov.
These are: Trichorhina acuta from Brazil; T. argentina from Argentina; T. australiensis Wahrberg, Tab. I. Brazilian records of species of Trichorhina by microhabitats, regions and reference.