Digital Commons @ University of South Florida Digital Commons @ University of South Florida The cavernicolous Oniscidea (Crustacea: Isopoda) of Portugal. The cavernicolous Oniscidea (Crustacea: Isopoda) of Portugal. European Journal of Taxonomy European Journal of Taxonomy

. The study of subterranean Oniscidea in Portugal has been neglected for nearly 70 years, but recent investigations have revealed high diversity. All the terrestrial isopods known from caves of mainland Portugal, including data from the literature and new material, are listed, revealing new biodiversity patterns. Twenty-seven species, belonging to 15 genera and six families, are known, of which 16 species are considered to be exclusively from subterranean ecosystems, i.e., troglobionts. Trichoniscidae is the most diverse family. Seven species in the family Trichoniscidae and one species in the family Styloniscidae are described as new (all with Reboleira & Taiti as authors): Trichoniscoides bellesi sp. nov. from the Montejunto Massif; T. sicoensis sp. nov. from the Sicó Massif; Metatrichoniscoides salirensis sp. nov. from the typhonic valley of Caldas da Rainha; Troglonethes olissipoensis sp. nov. from the Lisbon Peninsula; T. arrabidaensis sp. nov. from the Arrábida Massif; Miktoniscus longispina sp. nov. from the Sicó Massif and Cesaredas Plateau; Moserius inexpectatus sp. nov. from the Estremenho Massif; and Cordioniscus lusitanicus sp. nov. from Alentejo and Algarve, the southernmost provinces of Portugal. The subgenus Trogleluma Vandel, 1946 (Armadillidiidae) is raised to genus level. In this geographic region terrestrial isopods are the richest group of cave-adapted animals.


Introduction
Terrestrial isopods (suborder Oniscidea) play a very important role in the decomposition of organic matter in land ecosystems (Hornung 2011). In subterranean ecosystems they occupy a key-ecological position, recycling organic detritus and being frequent prey of cave predators (Řezáč et al. 2008). Terrestrial isopods are successful land colonizers, but a great majority of species have a high dependence on hygrophilous habitats (Hornung 2011). In fact, they are quite abundant in subterranean ecosystems. Several species of oniscideans have adapted to the aphotic environment, where they can be found in the terrestrial and in the aquatic compartment, including species with amphibian behaviour (Taiti & Xue 2012;Broly et al. 2013;Campos-Filho et al. 2014).
Oniscidea represent the most diverse group among the Portuguese cave-obligate fauna (Reboleira et al. 2011a. Taxonomic studies on the Oniscidea from mainland Portugal are scarce and included mainly in two publications recording epigean and subterranean species by Arcangeli (1935a) and Vandel (1946), based on material collected by A. Barros Machado (for a complete list of Portuguese terrestrial isopods see Schmalfuss 2003).
Prior to this study, only seven species of Oniscidea had been recorded as cave-adapted from karst massifs in mainland Portugal (Reboleira et al. 2011a. Five species in the family Trichoniscidae were known: one from the north of the country (Trichoniscoides serrai Cruz, 1993) and four from central Portugal, i.e., Trichoniscoides broteroi Vandel, 1946 from the Sicó karst massif, and T. subterraneus Vandel, 1946, T. meridionalis Vandel, 1946and T. ouremensis Vandel, 1946 from the Estremenho karst massif. The family Porcellionidae was represented by the species Porcellio cavernicolus Vandel, 1946, known from Sicó, and the family Armadillidiidae by Troglarmadillium (Trogleluma) machadoi Vandel, 1946, found in caves of the Algarve in the south of the country (Vandel 1946;Cruz 1993).
Recent investigations in caves of karst areas from Portugal revealed the presence of several new species of terrestrial isopods. The oniscidean fauna from the subterranean environment of mainland Portugal is here discussed based on literature data and the new material examined.

Material and methods
Field work was performed between 2007 and 2014 in many karst caves from mainland Portugal and terrestrial isopods have been collected in 29 of these caves (Table 1, Fig. 1). The original Portuguese names for caves are maintained throughout the text, i.e., "Gruta" for a horizontal cave, "Algar" for a vertical cave and "Lapa" for a small cave.
Each cave was monitored in two different zones: just beyond the twilight zone and in its deeper parts. Specimens were collected using baited pitfall traps and active search in each cave, and most were preserved in 70% ethanol, while some specimens were preserved in 100% ethanol for future molecular analyses. Temperature was measured with an Aspiration Psychrometer 761 (Lambrecht, Göttingen).
Identifications are based on morphological characters and the pertinent literature. The terminology used in species descriptions is mainly based on Vandel (1960aVandel ( , 1962. Specimens were studied under Wild European Journal of Taxonomy 161: 1-61 (2015) M5 and M20 microscopes and figures drawn with the aid of a camera lucida. Parts of specimens were mounted in micropreparations with Hoyer's liquid (Anderson 1954).

Remarks
No specimens of this species were collected during our research. The type locality is now closed by the municipality and the whole surrounding area is urbanized.

Remarks
The diagnostic features of this species, i.e., the male pereopod 7 and male pleopods 1 and 2, are illustrated in Fig. 2 from specimens collected in Gruta d'el Rey.

Distribution
Species endemic to Portugal where it is widely distributed, from Serra do Gerês in the north to the Algarve in the south.

Distribution
Species endemic to Portugal, presently only known from the type locality. Cruz, 1993 Trichoniscoides serrai Cruz, 1993:

Distribution
This species is restricted to the Estremenho karst massif, in central-western Portugal.

Remarks
This form was described by Vandel (1946) as a subspecies of Trichoniscoides pseudomixtus (Arcangeli, 1935), a species present in some caves of northeastern Spain. Vandel (1952a) elevated this form to species level. The male pereopod 7 and male pleopods 1 and 2 are illustrated in Fig. 3 from specimens collected in Gruta dos Moinhos Velhos.

Ecological notes
This species can be found from the entrances to the deepest parts of the caves, normally associated with decomposing wood. It is distributed along the three main subunits of the Estremenho Massif, being the only troglobiotic oniscidean so far known from this large karst area. Contrary to other troglobiotic arthropods from the same massif, it does not present closely related species along the three subunits (Reboleira 2007;Reboleira et al. 2009). The biocoenosis of this karst area includes other troglobionts, i.e., the spider Nesticus lusitanicus Fage, 1931, the campodeid Podocampa cf. fragiloides Silvestri, 1932, and the ground beetles Trechus gamae Reboleira & Serrano, 2009, T. lunai Reboleira & Serrano, 2009and T. machadoi Jeannel, 1941(Reboleira & Ortuño 2011Reboleira et al. 2010b). Reboleira & Taiti sp. nov. urn:lsid:zoobank.org

Diagnosis
A blind and colourless Trichoniscoides characterised by the male pleopod 1 exopod having a broadly rounded outer margin and two equal distal lobes, and the male pleopod 2 endopod having a distal article thickset for ⅔ of its length, ending with a narrow point.

Etymology
The new species is named after Prof. Xavier Bellés for his invaluable contribution to the synthesis of knowledge on the subterranean fauna from the Iberian Peninsula.

Description
Maximum size: ♂ 1.7 × 0.8 mm; ♀ 1.8 × 0.8 mm. Body colourless and slightly convex (Fig. 4A). Cephalon and pereon with granulated dorsal surface; granules on pereonites arranged in double rows; each granule bearing a triangular scale-seta (  long, distal part trapezoidal with concave sides and slightly convex apex. Antennula ( Fig. 4F) with three articles; third article with distinct spine and three long aesthetascs at apex. Antenna ( Fig. 4G) with fifth article of peduncle shorter than flagellum; flagellum with three articles, with three long aesthetascs on second article. Mandibles ( Fig. 5A-B) with two penicils on the right and three on the left; molar process without penicils. Maxillula (Fig. 5C) with inner branch bearing three penicils at apex, proximal one distinctly longer than other two; outer branch with 11 teeth and two thin stems, one among outer group and one among inner group of teeth. Maxilla (Fig. 5D) apically bilobed, with outer lobe smaller than inner one; inner lobe with several long, stout setae. Maxilliped (Fig. 5E) endite triangular, with stout penicil at apex; palp distally rounded, with long setae, basal article with two short, compound setae. Uropod ( Fig. 4E) with exopod distinctly longer than endopod; exopod with several long, pointed setae and endopod with a long and a short seta at apex.
Male. Pereopod 1 (Fig. 6A) and pereopod 7 ( Fig. 6B) with no particular modifications. Pleopod 1 (Fig.  6C) exopod almost as long as wide, with broadly rounded outer margin and two equal distal lobes each bearing a short seta at apex; endopod with triangular and flagelliform basal article and setose distal article. Pleopod 2 exopod missing in the specimen examined; endopod ( Fig. 6D) biarticulated, distal article about twice as long as basal one, thickset for first ⅔ and ending with narrow point.

Remarks
In the shape of the male pleopod 2 exopod, with a thickset distal article ending in a narrow point, the new species is similar to Trichoniscoides lusitanus Vandel, 1946, T. broteroi andT. heroldi Vandel, 1952. It differs from T. lusitanus, an epigean species from north-western Spain and northern Portugal, in lacking eyes and pigment, in the male pleopod 1 endopod having a triangular basal article, and in the male pleopod 2 endopod having a stouter distal article ending in a shorter point; from T. broteroi in lacking the hook on the male pereopod 7 merus, and in the triangular shape of the basal article of the male pleopod 1 endopod; from T. heroldi, an epigean species from eastern France, in the lack of eyes and the shape of the male pleopod 1.

Ecological notes
Trichoniscoides bellesi sp. nov. is typically a troglobiotic species, lacking eyes and body pigment. It was discovered in the deepest and most thermally insulated parts of Algar do Javali, around 10 m deep. Javali is currently the richest cave of the Montejunto karst massif. Four other caves in the same massif were also sampled (Algar do Escorpião, Ralo das Fontaínhas, Algar da Terra da Rolha and Buracos Mineiros) without recovering any specimens of T. bellesi. The subterranean community of Algar do Javali includes other troglobiotic species, such as the campodeid Podocampa cf. fragiloides, a species of the oniscidean genus Paraschizidium (see below), the ground beetle Trechus tatai Reboleira & Ortuño, 2010, a new pselaphid beetle, and the pseudoscorpions Chthonius cardosoi Zaragoza, 2012 and Roncocreagris occidentalis Zaragoza & Reboleira, 2013(Reboleira et al. 2010a, 2013c. Reboleira & Taiti sp. nov. urn:lsid:zoobank.org

Diagnosis
A blind and colourless Trichoniscoides characterised by the male pereopod 7 merus having a lobe on the mid-sternal margin, the male pleopod 1 exopod having a broadly rounded outer margin and two unequal setae, the endopod having a fusiform distal article with a distinct circular suture in the middle, and the male pleopod 2 endopod having thickset distal article bearing two short triangular lobes and two setae at the apex.

Etymology
The new species is named after the Sicó karst area, where the species occurs.  article with two short compound setae. Uropod ( Fig. 7E) with exopod distinctly longer than endopod and more distally inserted; exopod with several long, pointed setae and endopod with a long and a short seta at apex.
Male. Pereopods 1 (Fig. 9A) to 3 with an area of short quadrangular scales on sternal margin of carpus and merus. Pereopod 7 (Fig. 9B) merus with distinct cylindrical lobe, with short seta at apex on mid-sternal margin. Genital papilla (Fig. 9C) fusiform. Pleopod 1 (Fig. 9D) exopod as long as wide, with broadly rounded outer margin and two unequal setae on distal lobe; endopod with basal article quadrangular with convex inner margin and concave outer margin, distal article fusiform with distinct suture in middle and setose apex. Pleopod 2 (Fig. 9E) exopod trapezoidal with large seta at apex; endopod biarticulated, distal article about 1.5 times as long as basal one, thickset, with two short triangular lobes and setae at apex.

Remarks
This new species is tentatively included in the genus Trichoniscoides since it has all the characters of the genus, except for the distal article of the male pleopod 1 endopod, which shows a distinct circular suture in the middle, and the thickset distal part of the male pleopod 2 endopod. These characters are present also in an epigean species described by Gregory et al. (2012: 7, fig. 4) as "? Trichoniscoides species C" from Avión, valley of Río Valdeiras, Orense, north-western Spain, and Castanheira, Viana do Castelo, northern Portugal. The new species differs from the one recorded by Gregory et al. (2012) in the shape of the basal article of the male pleopod 1 endopod and of the distal part of the male pleopod 2 endopod. Trichoniscoides sicoensis Reboleira & Taiti sp. nov., together with the species recorded by Gregory et al. (2012), might belong to a distinct genus, but this can only be confirmed when other species with similar characters are found. For the presence of a lobe on the mid-sternal margin of the male pereopod 7 merus, the new species also resembles T. broteroi, from which it is distinguishable by the shape of the male pleopods 1 and 2. A hook-like lobe on the sternal margin of the male pereopod 7 merus is present also in the "aquitano-languedocien" group of species (sensu Vandel 1960a), but in the species of this group the lobe is near the base instead of being on the mid-part of the sternal margin.

Ecological notes
This species seems to be endemic to caves of the Sicó karst area. In Gruta do Soprador do Carvalho one specimen was collected under a stone completely submerged in the cave stream. Despite the amphibian behaviour and submersion tolerance, this species is mostly found in the superficial parts of caves, where roots are abundant. Several troglobiotic species are known to share this habitat with T. sicoensis Reboleira &Taiti sp. nov Reboleira & Oromí, 2011(Reboleira et al. 2011bEnghoff & Reboleira 2013a).

Diagnosis
A blind and colourless Metatrichoniscoides characterised by the male pleopod 1 exopod having two long distal setae subequal in length, and the male pleopod 2 endopod having a thickset distal article, ending in a thinner sinuous part with a beak-like small lobe medially directed.

Remarks
Until now the genus Metatrichoniscoides included only four species (Schmalfuss 2003): M. leydigii (Weber, 1880) from western France, Belgium, the Netherlands, western Germany and greenhouses in the Czech Republic, Sweden and Finland; M. nemausiensis Vandel, 1942 andM. fouresi Vandel, 1950 from France; and M. celticus Oliver & Trew, 1981 from Wales (Vandel 1942;Oliver & Trew 1981). Metatrichoniscoides salirensis Reboleira & Taiti sp. nov. is readily distinguished from all the other species in the genus by the male pleopod 1 exopod bearing two long setae and the peculiar shape of the male pleopod 2 endopod. This represents the first record of the genus for Portugal and the Iberian Peninsula.

Ecological notes
Gruta de Salir is a peculiar, beautiful cave located near the sea, with a genesis related to previous sea levels, evidenced by the presence of marine sand in the lowest parts. This is the first troglobiotic species known from this cave and this karst area.

Diagnosis
A species of Troglonethes characterised by the antenna having five flagellar articles, the male pleopod 1 exopod triangular, as wide as long, and the male pleopod 2 endopod with the distal article bearing a basal and a distal hook-like process.

Etymology
The new species is named after Olissipo, the old name of Lisbon, on the peninsula of which the Gruta de Alvide is located.

Description
Maximum size: ♂ 3.5 × 0.8 mm; ♀ 4.2 × 1.2 mm. Body colourless and elongated (Fig. 13A). Dorsum of cephalon and pereon granulated; each granule equipped with a triangular scale-seta (Fig. 13B); pleon and telson smooth. Cephalon (Fig. 13C-D) with quadrangular frontal lateral lobes slightly protruding outwards. Eyes absent. Pereonites 1-4 ( Fig. 13A) with rounded posterior corners; pereonites 5-7 ( Fig.  13A) with epimera pointing backwards. Pleon (Fig. 13A, E) narrower than pereon; pleonites 3-5 with small epimera and very short posterior points. Telson (Fig. 13E) about twice as wide as long, with distal part trapezoidal with concave sides. Antennula (Fig. 13F) with three articles; third article with spine and three long aesthetascs at apex. Antenna (Fig. 13G) with third, fourth and fifth article of peduncle with distinct tubercles bearing scale-setae; fifth article as long as flagellum; flagellum with five articles, with two long aesthetascs on second and third article. Mandibles (Fig. 14A-B) with one penicil on the right and three on the left. Maxillula (Fig. 14C) with inner branch bearing three penicils at apex, inner one distinctly longer than other two; outer branch with 12 teeth and thin, setose stem among outer group of teeth. Maxilla (Fig. 14D) apically bilobed and setose, with outer and inner lobes subequal; inner lobe with several long stout setae along margin. Maxilliped (Fig. 14E) endite triangular, with stout triangular penicil at apex; palp distally rounded, with long setae, basal article with two short, compound setae. Uropod (Fig. 13E) with exopod slightly longer than endopod and more distally inserted; exopod with several long pointed setae and endopod with a long and a short seta at apex. Male. Pereopod 1 (Fig. 15A) with no particular modifications. Pereopod 7 (Fig. 15B) ischium with straight sternal margin, carpus with row of scales on distal margin, and propodus with long, thin setae on distal half of tergal margin. Genital papilla (Fig. 15C) fusiform, with rounded apex, much longer than pleopod 1. Pleopod 1 (Fig. 15C) exopod triangular, as wide as long, with broadly rounded apex; endopod with basal article elongated, longer than exopod, with sinuous outer margin, distal article flagelliform with setose apex. Pleopod 2 (Fig. 15D) exopod triangular, with broadly rounded apex with few short setae; endopod biarticulated, basal article about three times as long as distal one, with parallel sides, distal article with outer margin bearing hook-like process at base and one at apex.

Remarks
The genus Troglonethes was erected by Cruz (1989) for the new species T. aurouxi from a cave north of Valencia, Spain. Tabacaru (1993) included the genus in the tribe Speleonethini. The new species from Portugal is included in the genus since it has all the characters listed in the diagnosis. Troglonethes olissipoensis Reboleira & Taiti sp. nov. differs from T. aurouxi in having an antennal flagellum with five, instead of four, articles, the male pleopod 1 exopod shorter than the basal article of the endopod, and the male pleopod 2 endopod with a basal hook-like process on the outer margin of the distal article.

Ecological notes
This species was only found in Gruta de Alvide, located in an overurbanized area, with part of the cave ceiling used as the base of a residential building. The specimens were collected in the deepest parts of the cave, the so-called third level. It is the second troglobiotic species from karst caves in the Lisbon Peninsula, after the record of the bristletail Coletinia sp. in Gruta de Colaride (Reboleira et al. 2012a). Unidentified springtails and blaniulid millipedes were also collected.

Diagnosis
A species of Troglonethes characterised by the antenna having three flagellar articles, the male pereopod 7 carpus enlarged in the basal part, the pleopod 1 exopod triangular, as wide as long, and the male pleopod 2 endopod with the distal article bearing an apical hook-like process.

Etymology
The new species is named after the type locality, the Arrábida karst massif.

Description
Maximum size: ♂ and ♀ 2.7 × 0.8 mm. Body colourless and elongated (Fig. 16A). Dorsum of cephalon and pereonites with two rows and one row of large granules, respectively; each granule with a scale-seta (Fig. 16B); pleon and telson smooth. Cephalon (Fig. 16C-D) with short, quadrangular frontal lateral lobes. Eyes absent. Pereonites 1-3 with rounded posterior corners; pereonites 4-7 with epimera pointing backwards (Fig. 16A). Pleon (Fig. 16A, E) slightly narrower than pereon; pleonites 3-5 with small epimera and very short posterior points. Telson (Fig. 16E) about twice as wide as long, with distal part trapezoidal, with concave sides and broadly rounded apex. Antennula (Fig. 16F) with three articles; third article with three long aesthetascs at apex. Antenna (Fig. 16G) with fourth and fifth article of peduncle with distinct tubercles bearing scale-setae; fifth article slightly shorter than flagellum; flagellum with three articles, with two long aesthetascs on second article. Buccal pieces as in previous species. Uropod (Fig. 16E) with exopod slightly longer than endopod, exopod and endopod inserted at same level.

Remarks
The new species is very similar to Troglonethes aurouxi in the dorsal granulation and shape of the male pleopod 2. It differs in having the antennal flagellum with three, instead of four, articles, and a wider male pleopod 1 exopod. It is readily distinguishable from T. olissipoensis Reboleira & Taiti sp. nov. in the larger and less numerous dorsal granules, the enlarged basal part of the male pereopod 7 carpus, the male pleopod 1 endopod with the basal article shorter than the exopod, and the distal article of the male pleopod 2 endopod lacking the hook-like process at the base.

Ecological notes
This species was only found in the Gruta do Frade in the Arrábida Massif. The cave entrance is by the seashore and there are several anchialine lakes inside, influenced by the sea tides. It is the first record of troglobiotic terrestrial isopods in Arrábida.

Description
Maximum size: ♂ and ♀ 3.5 × 1.0 mm. Body depigmented, elongated (Fig. 18A). Dorsum of cephalon and pereon distinctly granulated, each granule bearing a scale-seta on top (Fig. 18B). Cephalon (Fig.  18C) with no frontal lobes. Eye consisting of single black ocellus (lacking in specimens from Gruta da Cerâmica and Algar da Ervilha). Pereonites 1-4 with rounded posterior corners; pereonites 5-7 with epimera pointing backwards (Fig. 18A). Pleon (Fig. 18A, D) slightly narrower than pereon; pleonites 3-5 with reduced epimera and very short posterior points. Telson (Fig. 18D) about twice as wide as long, with rectangular basal part and trapezoidal distal part, with almost straight sides. Antennula (Fig. 18E) with three articles; third article with short spine and four long aesthetascs at apex (five in specimens from Gruta da Cerâmica and Algar da Ervilha). Antenna (Fig. 18F) with fifth article of peduncle slightly longer than flagellum; flagellum with four articles, with one aesthetasc on second article and two aesthetascs on third article (two and four, respectively, in specimens from Gruta da Cerâmica and Algar da Ervilha). Mandibles (Fig. 19A-B) with one penicil on the right and two on the left; molar process without penicils. Maxillula (Fig. 19C) with inner branch bearing three penicils at apex, diminishing in size from proximal to distal; outer branch with nine teeth and thin stem. Maxilla (Fig. 19D) apically bilobed, outer lobe smaller and shorter than inner one; inner lobe with line of several long, stout setae near apical and inner margins. Maxilliped (Fig. 19E) endite triangular, with stout triangular penicil at apex; palp elongated, with long setae on margin of apical part, and basal article with two short, simple setae. Uropod (Fig. 18E) with exopod distinctly longer than endopod and more distally inserted. Male. Pereopod 1 (Fig. 20A) with no distinct sexual modifications. Pereopod 7 (Fig. 20B) ischium triangular, with strong seta, as long as merus, at corner between distal and sternal margin; sternal margin of merus sinuous, with one recurved seta and one pointed seta in the middle; carpus with distal part enlarged, with some strong setae on sternal margin. Pleopod 1 (Fig. 20C)  twice as long as wide; endopod with basal article distinctly shorter than distal article, which is slightly enlarged subapicaly, with triangular and crenulated apical part. Pleopod 2 (Fig. 20D) exopod triangular, with distinctly concave outer margin; endopod biarticulated, distal article fusiform, elongated, about four times as long as first article.

Remarks
At present, the genus Miktoniscus includes 15 species distributed in the Americas and Western Europe, including the Atlantic islands (Schmalfuss 2003). The new species is readily distinguishable from all species in the genus by the presence of a strong and long seta at the distal corner of the male pereopod 7 ischium. In continental Portugal and northwestern Spain only one species was previously known, Miktoniscis bisetosus Vandel, 1946, from which M. longispina Reboleira & Taiti sp. nov. also differs in lacking a recurved seta on the male pereopod 7 carpus and in having the male pleopod 1 exopod with an acute, rather than broadly rounded, apex. The new species occurs in two distinct massifs of central Portugal, on the west border of Cesaredas Plateau near the Atlantic coast, and in Gruta da Cerâmica and Algar da Ervilha in the centre of Sicó Massif. Some differences are present in the specimens from Sicó compared with the type specimens from Cesaredas, i.e., the lack of visible eyes and the different number of aesthetascs on the antennula and antennal flagellum. For this reason, we have not designated the additional material as paratypes. However, since the male characters are the same in all these populations, we consider them as belonging to the same species.

Distribution
Portugal, Spain, southern Italy and Sicily.

Diagnosis
A species of Moserius characterised by the male pereopod 7 carpus having a distal lobe on the sternal margin, and the pleopod 1 exopod having a truncate and sinuous distal point.

Etymology
From Latin inexpectatus = unexpected. The name refers to the location, which is far from the previously known distribution range of the genus.

Remarks
This new blind species belongs to the subfamily Haplophthalminae and is included in Moserius since it shows the tergal ornamentation typical of the genus, i.e., 3 + 3 ribs on the pereonites and two large tubercles on pleonite 3. The genus Moserius was previously known only for two species: M. percoi Strouhal, 1940, originally described from the cave Belinca Jama, Slovenia, and later recorded from Ligurian and Tuscan caves (Strouhal 1940;Brian 1963;Taiti & Ferrara 1995), and M. elbanus Taiti & Ferrara, 1995, from a small cave on Elba Island, Tuscany, Italy. The new species is readily distinguished from the other two members of the genus by the peculiar shape of the male pleopod 1 exopod, with a truncate and sinuous, rather than triangular, distal point. The location of M. inexpectatus (Portugal) is very far from those of the other two species (northern Italy and Slovenia), but it is quite probable that other species are present in the countries encompassing the northwestern Mediterranean.

Ecological notes
This species occurs in the Gruta do Almonda, the largest Portuguese cave, with at least 10 km of mapped subterranean galleries. It shares habitat with other troglobiotic species, namely the spider Nesticus lusitanicus Fage, 1931, the woodlouse Trichoniscoides meridionalis, and the beetle Trechus lunai Reboleira & Serrano, 2009(Reboleira et al. 2009).

Diagnosis
A blind species of Cordioniscus characterised by a colourless body, the male pereopod 7 ischium having a rounded hyaline basal lobe, the triangular male pleopod 1 exopod, as long as the endopod, and the complex apical part of the male pleopod 2 endopod.

Etymology
From Latin lusitanicus = Portuguese. The name refers to the country where the specimens were collected.

Remarks
This epigean species was recently discussed and fully illustrated by Taiti & Rossano (2015), who considered it to be a senior synonym of Ctenoscia dorsalis (Verhoeff, 1928).

Distribution
Known with certainty from southern Portugal and southern Spain (Schmölzer 1971).

Remarks
Trichorhina anophthalma is fully illustrated here (Figs 26-27) to facilitate its identification. Hoese (1984) recorded this species from the Canary Islands (Fuerteventura and Tenerife) and considered T. hoestlandti Vandel, 1960from Madeira (Vandel 1960b to be a junior synonym of that species. Contrary to this, Schmalfuss (2003) regarded both species as valid. A re-examination of specimens of Trichorhina hoestlandti from Madeira is necessary in order to define the taxonomic status of this species. The specimens of Trichorhina from the Canary Islands recorded by Hoese (1984) also need to be examined for a correct identification.

Distribution
Southern British Isles, western France, Portugal, Azores, Madeira, Canary Islands, mainland Spain and north-western Africa. It has been introduced to Tasmania and French Guyana.

Distribution
This species seems to be endemic to central Portugal.
The numerous specimens collected during our research allow us to illustrate the species with its most important features, i.e., the tuberculated body and the schisma on pereonite 1 (Fig. 30A), the cephalon (Fig. 30B), the telson and uropods (Fig. 30C), and the antenna (Fig. 30D). This species has a very plastic morphology concerning the dorsal tubercles, which may be more or less developed. The presence of several adult males permits the description of the male characters which were previously unknown: Pereopods 1 (Fig. 30E) to 6 with brushes of setae on sternal margins of merus and carpus. Pereopod 7 (Fig. 30F) ischium narrow, with straight sternal margin and a ridge on distal part of caudal surface. Pleopod 1 (Fig. 31A) exopod with long, rounded median lobe directed outwards, endopod with distal half having parallel sides and small recurved and pointed apical part not protruding outwards. Pleopod 2 (Fig. 31B) exopod triangular and slightly shorter than endopod.

Ecological notes
This troglophilic species was collected with traps in the MSS (mesovoid shallow substratum, or 'milieu souterrain superficiel' sensu Juberthie et al. 1980) in the Estremenho Massif as well as in a cave (Gruta Soprador do Carvalho) in Sicó.

Remarks
At present, the genus Paraschizidium includes with certainty only three species: P. coeculum (Silvestri, 1897), distributed from Spain to the Balkans, P. hispanum Arcangeli, 1935from southern Spain, and P. roubali Frankenberger, 1940from Prague, Czech Republic (Frankenberger 1940, which is probably a junior synonym of P. coeculum (see Manicastri & Taiti 1994). Other species from Greece originally included in the genus Paraschizidium by Schmalfuss (1981) and Sfenthourakis (1992Sfenthourakis ( , 1995 were transferred to the genus Schizidium Verhoeff, 1901by Schmalfuss (2008. Our specimens certainly belong to the genus Paraschizidium: they are depigmented and blind, have no schisma at the posterolateral corner of the pereonite 1 (Fig. 32A), the cephalon has oblique antennal lobes ( Fig. 32B-C), the telson is short and triangular (Fig. 32D) and the antennula has two articles (Fig. 32E). Unfortunately, the absence of males in our material does not permit the identification of these specimens to species level.
Genus Trogleluma Vandel, 1946 Remarks Trogleluma was erected by Vandel (1946) as a subgenus of Troglarmadillidium Verhoeff, 1900 to include the new species Troglarmadillidium (Trogleluma) machadoi from two caves in South Portugal (see below). At present, the genus Troglarmadillidium only includes the monospecific subgenera Troglarmadillidium and Trogleluma, with the species T. (Troglarmadillidium) stygium (Verhoeff, 1900) from Herzegovina, and T. (Trogleluma) machadoi. Both these species have a depigmented body, are blind, have no schisma at the postero-lateral corner of pereonite 1, a triangular telson, and uropods with the exopodite flattened, longer than wide. The two subgenera show quite distinct morphological traits in the cephalic structure: in Troglarmadillidium the triangular frontal scutellum of the cephalon, frontal line and antennal lobes are missing, while in Trogleluma these structures are present. These characters have been confirmed after the examination of a fremale specimen of T. (Troglarmadillidium) stygium from Montenegro (Crna Gora, Danilovgrad, Tunjevo, Milojevića vrela, 26 Apr. 1997, leg. and det. I. Karaman). On the basis of these characters we consider Trogleluma as a distinct genus from Troglarmadillidium. Trogleluma includes the type species, Trogleluma machadoi, and a few undescribed new species from Sardinia and Tuscany in Italy (Taiti 2007, unpublished results).

Distribution
Endemic to caves of the Algarve, the southernmost province of Portugal.

Remarks
The species is here fully illustrated (Figs 33-34) to facilitate its recognition.

Ecological notes
Troglobiotic species. The specimens were mostly found inside the clay, which often covers their integument, an observation already pointed out by Vandel (1946). Some individuals were also found walking on cave walls and completely clean of clay.

Discussion
Terrestrial isopods are the most diverse taxonomic group of troglobionts  in the caves of Portugal, with the number of known species doubled with the present work. The Portuguese oniscidean fauna is now composed of 16 troglobiotic species in mainland Portugal, 5 troglophiles and 6 trogloxenes (  The family Platyarthridae is represented by the species Trichorhina anophthalma, described from endogean habitats in Palmela, the Arrábida karst massif and Serpa (Baixo Alentejo), but recently also found in karst caves of Alandroal in central Alentejo and in the Algarve.
The family Porcellionidae has one troglobiotic species, Porcellio cavernicolus, described from the Sicó Massif, but now found in caves of the Outil-Cantanhede and Mealhada karst areas, north of the Mondego River, and also inhabiting caves in the Tomar region, significantly increasing its former area of distribution. Slight morphological differences can easily be observed between the extremes of its area of distribution, and molecular studies may clarify the taxonomy of these isolated populations. This species is particularly abundant in shallow caves with roots pending from the ceiling. The troglophilic Porcellio dilatatus dilatatus is very abundant in the most superficial parts of caves from all of Portugal, a feature already pointed out by Vandel (1946).
The family Armadillidiidae is represented by four species belonging to the genera Eluma, Paraschizidium and Trogleluma. The genus Eluma includes the epigean E. caelata and E. tuberculata, originally described from specimens collected under stones in the eastern subunit of the Estremenho Massif (Cruz 1991) and now found in the MSS on the western border of the same massif and also in one cave of Sicó. It appears to be distributed along the MSS, being found inside caves only in their most superficial areas. One cave-adapted species of Paraschizidium was found in a cave of the Montejunto Massif and represents the first record of this genus in Portugal. Trogleluma machadoi is widely distributed in caves along the Barrocal area in the Algarve karst massif.
From a biospeleological point of view, mainland Portugal is traditionally divided into two main areas, the Lusitanian district in central Portugal, and the Baetic district in the south, including the Algarve and extending to Andalucia in Spain (Bellés 1987;Reboleira et al. 2011a). The pattern of troglobiont richness for terrestrial isopods reinforces this separation, with the Lusitanic district clearly rich in troglobiotic species of the genus Trichoniscoides and the Baetic district characterised by the presence of the genera Trogleluma and Cordioniscus.
The recent rise in the number of known subterranean species is a result of the extensive use of a standard sampling methodology in a large number of karst caves, which has also provided new taxa of other caveadapted arthropod groups (Reboleira 2012;Reboleira et al. 2009Reboleira et al. , 2010aReboleira et al. , 2010bReboleira et al. , 2010cReboleira et al. , 2011bReboleira et al. , 2012aReboleira et al. , 2012bReboleira et al. , 2013bReboleira & Enghoff 2014a). The richness of terrestrial isopods in the subterranean ecosystems of Portugal, and by extension of the Iberian Peninsula, requires a consistent sampling effort to reach a complete level of evaluation.
Terrestrial isopods have been used as bioindicators in land ecosystems, since they are extremely sensitive to contaminants (Paoletti & Hassall 1999;Paoletti et al. 2007). In the same way, the presence of troglobiotic Oniscidea can be used as indicators of subterranean ecosystem health. A strong argument in support of this is their basal trophic position in cave communities. Decomposing detritus and their strong dependence on water makes them more vulnerable to contamination. The presence of troglobiotic oniscidean species is generally related to deep, stable and undisturbed parts of caves, while in the most disturbed areas only trogloxenes or, at most, troglophile isopods are present, suggesting that they can be used as indicators of the quality of the subterranean ecosystems that they occupy. An example of this is provided by the Gruta dos Moinhos Velhos, with a 300 m long show cave branch, where only the troglophile Porcellio dilatatus dilatatus is abundant, while the troglobiont Trichoniscoides meridionalis occurs only in the undisturbed galleries, far from human impact. All troglobiotic species of Oniscidea in Portugal lack formal protection ) and their biodiversity patterns should be considered for sustainable management of karst areas in such an important world biodiversity hotspot.