Trichoniscoides gallaecus, da Silva, 2023

Trichoniscoides gallaecus View in CoL n. sp.

( Figs. 2 View Figure 2 , 3 View Figure 3 ; Gregory et al., 2012: 12, fig. 2)

Zoobank: urn:lsid:zoobank.org:act:3D8DCDF5-B8E0-4980-A492-802D7A223D3B

Type material. Holotype: male ( MNCN 20.04 About MNCN /20602), 27May2022, Fradelos , Braga, Portugal, (41°21’16”N 8°36’22”W), coll. L.P.da Silva. GoogleMaps Paratypes: 2 females (INV18000, INV18001), 27 March 2022, same data as holotype GoogleMaps ; 1 male (JC667), same data as holotype GoogleMaps ; 4 females (INV18002, INV18003, JC668, MNCN 20.04 About MNCN /20568), same data as holotype GoogleMaps .

Diagnosis. Dark red coloration. Eye apparatus composed of single large ocellus. Integument with granulations. Antennae with scaly tubercles and 3 flagellar segments. Male pereopods 1 and 7 with sexual dimorphism. Male pleopods: endopod I with large triangular distal lobe; exopod I trapezoidal, with 2 very different hairy protuberances; endopod II very wide, narrowing sharply near tip; exopod II trapezoidal, lacking inner tip.

Description. Maximum observed length: female 2.5 mm, male 2.1 mm. Coloration intense dark red ( Fig. 2A, B View Figure 2 ), stable in ethanol for at least 6 months, interrupted by light color from muscle attachments. Tegument covered by granulations ( Fig. 2A, B View Figure 2 ) with large triangular scale-setae with crenated edge surrounded by accessory scales ( Fig. 3A View Figure 3 ). Cephalon with 5 granulation rows, including 1 row on posterior edge. Pereon with 3 rows on first pereonite and 2 rows on remaining pereonites, plus another row on posterior edge of each tergite. These granulations fading towards posterior region. Pleon with row of small granulations on posterior edge of all pleonites. Eye apparatus formed by large ocellus ( Fig. 2B View Figure 2 ) in black pigmented spot. Antennules with 3 segments, last one with group of 3 long aesthetascs ( Fig. 3B View Figure 3 ). Antennae short, and not reaching posterior edge of 2 nd pereon tergite and presenting hairy tubercles ( Fig. 3C View Figure 3 ). Antennal flagellum composed of 3 segments, first the shortest, second with group of long aesthetascs inserted in middle and extending behind insertion of 3 rd segment. Pereopod 1 of both sexes bearing fan-shaped group of setae in carpus tip ( Fig. 3D View Figure 3 ).

Male sexual characters: Pereopod 1 merus and carpus with hyaline scales ( Figs. 2C View Figure 2 , 3D View Figure 3 ), but in merus only present in distal half.Pereopod 7merus with strong curved hook ( Figs.2D View Figure 2 , 3E View Figure 3 ) inserted in middle and with small seta at hook tip. Pleopod I: endopod triangular, with large distal lobe ( Fig. 3F View Figure 3 ); exopod trapezoidal, with 2 hairy protuberances of very different sizes, internal one very small, external one very long and thick, getting progressively thinner until ending in sharp tip ( Figs. 2E, F View Figure 2 , 3G View Figure 3 ). Pleopod II: endopod surrounded by hyaline membrane( Figs. 2G View Figure 2 , 3H View Figure 3 ), with distal segment 3 times longer than basal segment, sharply narrowing at two-thirds of its length, ending in fine but flattened tip ( Figs. 2H View Figure 2 , 3H View Figure 3 ); exopod trapezoidal, lacking distal tip and bearing small hairy protuberance surrounded by many fan-shaped setae; these setae also on inner and outer edges ( Figs. 2G View Figure 2 , 3I View Figure 3 ).

Etymology. The specific epithet is a reference to gallaecus , a Latin word used by the Romans to identify the indigenous peoples who lived north of the Douro River in Portugal and a large part of Galicia ( Spain).

Ecology. Epigean species found below (or within) deep moist litter (usually> 10cm), mostly composed of dead leaves of Q. robur . It was found together with Porcellio herminiensis Vandel, 1946a , Porcellio debueni Dollfus, 1892 , and Trichoniscus pusillus s.l. Brandt, 1833. Gregory et al. (2012) mentioned that it can also be found beneath dead wood and stones among leaf-litter.

Distribution. The species is so far known from the northwest of Portugal, in the Minho region, and in the southwest of Galicia, Spain ( Fig. 1 View Figure 1 ).

Remarks. Gregory et al. (2012) found females of 3 mm length and males of 2.25 mm. They also mentioned that all pigmentation is rapidly lost after preservation in alcohol.