Ctenorillo intertidalis Cardoso & Ferreira, 2024

Cardoso, Giovanna Monticelli, M, Diego de, Bento, edeiros & Ferreira, Rodrigo Lopes, 2024, Unveiling a hidden diversity: descriptions of nine new species of Ctenorillo Verhoeff, 1942 (Isopoda, Armadillidae) discovered in Brazilian caves and their importance for conservation, Zoosystema 46 (5), pp. 95-132 : 108-110

Ctenorillo intertidalis Cardoso & Ferreira , n. sp.

( Figs 8-10 ; 27D ; 28F, G )

urn:lsid:zoobank.org:act:B61E5142-E53A-4AD7-AF85-B24944928069

TYPE MATERIAL.— Holotype. Brazil • 1 ♂ (6 mm; parts in slide); Ceará state; Jijoca de Jericoacoara municipality; Jeri _10 cave; 2°47’12”S, 40°30’12”W; 25.IX.2019; R. L. Ferreira leg.; ISLA96786 . Paratypes. Brazil • 2 ♂, 9 ♀; same data as holotype; ISLA96787 .

OTHER MATERIAL. — Brazil. Ceará state; Jijoca de Jericoacoara municipality • 10♂, 12 ♀; Jeri _4 cave; 2°47’18”S, 40°30’42”W; 25.IX.2019; R. L. Ferreira leg.; ISLA96788 1 ♂ in slide. Jeri _4 cave; ISLA96789 • 10 ♂, 11 ♀; Jeri _7 cave; 2°47’16”S, 40°30’34”W; 24.IX.2019; R. L. Ferreira leg.; ISLA96790 • 11 ♂, 7 ♀; Jeri _8; 2°47’17”S, 40°30’32”W; 24.IX.2019; R. L. Ferreira leg.; ISLA96791 • 1 ♂ in slide; Jeri _8; 24.IX.2019; R. L. Ferreira leg.; ISLA96792 • 7 ♂, 1 ♀; Duas bocas cave; 2°47’16”S, 40°30’33”W; 24.IX.2019; R. L. Ferreira leg.; ISLA96793 • 1 juv.; Jeri Novo cave ; 2°47’15”S, 40°30’33”W; 25.IX.2019; R. L. Ferreira leg.; ISLA 96800 .

ETYMOLOGY. — The new species name is a noun in apposition that refers to area in where the caves are located, close to the beach, in an intertidal area.

DIAGNOSIS.— Dorsum covered with conical tubercles and lateral ribs with three rows on cephalon (4, 2, 6); four rows on pereonite 1 (4, 7, 6, 7); two rows on pereonites 2-7 (8 +7); one row of four tubercles on pleonites 3-5; and two paramedian tubercles on telson. Pleopod 1 exopod distal portion round, sinuous outer margin; endopod with distal portion slightly bent outward, three times longer than exopod.

DISTRIBUTION. — Jericoacoara National Park, municipality of Jijoca de Jericoacoara, North of Ceará state.

DESCRIPTION

Maximum size: ♂ and ♀, 7.5 mm. Color grey with lateral margins depigmented. Dorsum covered with conical tubercles and lateral ribs ( Figs 8A, B ; 28F, G ): cephalon with three rows (4, 2, and 6 from front to back of vertex); pereonite 1 with 24 in four rows (4, 7, 6 and 7); pereonites 2-7 with 15 (8 + 7); pleonites 3-5 with one row of four tubercles; telson with two paramedian tubercles. Dorsal cuticle ( Fig. 28G ) with short triangular scale setae, pereonites 1-7 bearing one line of noduli lateralis per side on outer surface of posterior tubercle of second tubercle. Cephalon with frontal shield protruding above vertex; eye consisting of 10 ommatidia ( Figs 8A, C, D ; 28F ). Pereonite 1 with posterior margin sinuous at sides; inner lobe of schisma rounded, extending beyond posterior margin of outer lobe; pereonite 2 with triangular ventral tooth reaching epimeron posterior margin ( Fig. 8C ). Pereonites 2-7 ( Fig. 8A ) with wide quadrangular epimera slightly bent outwards. Telson ( Fig. 8E ) hourglass-shaped, proximal portion broader than distal portion. Antennula ( Fig. 8F ) of three articles, second article shorter than first and third, third article with four apical and five subapical aesthetascs. Antenna ( Fig. 8G ) short and stout, flagellum shorter than fifth article of peduncle; second article of flagellum about twice as long as first. Buccal pieces as C. pelado Cardoso & Ferreira , n. sp. ( Fig. 8 H-L), except maxillula ( Fig. 8J ) with 4+ 6 simple teeth. All pleopod exopods with monospiracular covered lungs. Uropod ( Fig. 9A ) protopod flattened, enlarged on basal portion; exopod outward, short, inserted dorsally close to medial margin of protopod.

Male

Pereopods without particular modifications ( Fig. 9B, C ). Pleopod 1 exopod ( Fig. 9D ) wider than long, distal portion round, sinuous outer margin; endopod three times longer than exopod, distal portion slightly bent outwards. Pleopod 2 endopod longer than exopod ( Fig. 9E ). Pleopods 3-5 exopods as in Figure 9 F-H.

HABITAT

Specimens of C. intertidalis Cardoso & Ferreira , n. sp. were found in six caves in quartzite outcrops on the shoreline ( Fig. 10A, B ), near the village of Jericoacoara, in the municipality of Jijoca de Jericoacoara. The climate is classified as hot and humid (Aw’sg. Köppen), with summer rains from January to July. Temperatures range from 25°C to 35°C, and the dry season lasts about six months and is often interrupted by heavy rains in October or September ( Alvares et al. 2013).

The new species was found in six out of eight sampled caves in the area. The caves are quite small presenting, on average, 14.48 (± 7.48) meters of horizontal projection. Thus, most of them were devoid of aphotic zones. Specimens of C. intertidalis Cardoso & Ferreira , n. sp. were observed under rocks, sheltered from the wind off the coast ( Fig. 10C ). The organic matter inside the caves consisted of plant debris (brought by the wind or the tides, in caves closer to the sea) and bat guano in some caves (produced by the piscivorous Noctilio leporinus ( Linnaeus, 1758)) . In some caves, individuals of C. intertidalis Cardoso & Ferreira , n. sp. were observed co-occurring with another isopod species ( Fig. 10D ). The external environment comprises a “restinga” ecosystem dominated by herbaceous vegetation, which grows along the dunes. Thus, there are few external shelters for these organisms. As the samplings that resulted in the discovery of this new species focused specifically on caves, the actual extent of C. intertidalis Cardoso & Ferreira , n. sp. habitat is currently unknown, but their distribution may be much wider than that observed in this work, especially considering the lack of troglomorphic traits in this species.

The region is inserted in the Jericoacoara National Park, so the area and the caves are currently protected. Nonetheless, it is noteworthy that there is no regulation of visitor access to these caves, and due to the region’s popularity as a tourist destination, uncontrolled foot traffic may inadvertently pose a threat to the invertebrate populations, including those of the newly discovered species.

REMARK

Ctenorillo intertidalis Cardoso & Ferreira , n. sp. resembles C. pelado Cardoso & Ferreira , n. sp. in the number of tubercles on pereonite 1 (24), however the disposition with the presence of a lateral rib is similar to C. ferrarai , differing from both by the number of tubercles on pereonites 2 to 7 (15).

Figures

FIG. 8. — Ctenorillo intertidalis Cardoso & Ferreira,n. sp., paratype (male,7.5 mm,ISLA96786):A, habitus,lateral view;B, disposition of dorsal tubercles;C, cephalon and pereonite 1, frontal view; D, cephalon and pereonite 1, dorsal view; E, pleonites 3-5, uropods and telson, dorsal view; F, antennula; G, antenna; H, right mandible; I, left mandible; J, maxillula; K, maxilla; L, maxilliped. Scale bar: 0.5 mm.

FIG. 9. — Ctenorillo intertidalis Cardoso & Ferreira, n. sp.paratype (male,7.5 mm, ISLA96786): A, uropod,B, pereopod 1; C, pereopod 7; D, pleopod 1 and genital papilla; E, pleopod 2; F, pleopod 3 exopod; G, pleopod 4 exopod; H, pleopod 5 exopod.

FIG. 10. — Ctenorillo intertidalis Cardoso & Ferreira, n. sp.: A, quartzite outcrops on the shoreline of Jericoacoara, with a cave entrance (yellow star); B, inner portion of a cave where specimens are found; C, Ctenorillo intertidalis Cardoso & Ferreira, n. sp. specimen; D, habitus in natural condition sharing the habitat (under rocks) with other isopods.

FIG. 27. — Habitus of the species of the genus Ctenorillo Verhoeff, 1942 discussed in the present paper:A, Ctenorillo ferrarai Campos-Filho, Araujo & Taiti,2014; B, Ctenorillo pelado Cardoso & Ferreira, n. sp.; C, Ctenorillo araguaia Cardoso & Ferreira, n. sp.; D, Ctenorillo intertidalis Cardoso & Ferreira, n. sp.; E, Ctenorillo ubajarensis Cardoso & Ferreira,n. sp.; F, Ctenorillo cearensis Cardoso & Ferreira,n. sp.; G, Ctenorillo quiteriensis Cardoso & Ferreira,n. sp.; H, Ctenorillo potiguar Cardoso & Ferreira, n. sp.; I, Ctenorillo iuiuensis n. sp.; J, Ctenorillo jequitinhonha Cardoso & Ferreira, n. sp. Scale bars: 1 mm.

FIG. 28. — SEM images of Ctenorillo Verhoeff, 1942 new species: A-D, Ctenorillo pelado Cardoso & Ferreira, n. sp.: cephalon, dorsal view (A); epimera 1-3, lateral view (B); pleopod 3 exopod (C); epimera 1 and 2, ventral view (D); E, Ctenorillo araguaia Cardoso & Ferreira, n. sp.:, cephalon and epimera 1-3, lateral view; F, G, Ctenorillo intertidalis Cardoso & Ferreira, n. sp.: cephalon, frontal view (F); epimera 1-3, lateral view (G); H, Ctenorillo ubajarensis Cardoso & Ferreira,n. sp.: cephalon and epimera 1-3, lateral view;I, Ctenorillo potiguar Cardoso & Ferreira, n. sp.: cephalon and epimera 1 and 2, lateral view; J, K, Ctenorillo jequitinhonha Cardoso & Ferreira, n. sp.: cephalon, frontal view (J); cephalon and epimera 1 and 2, lateral view (K). Scale bars: A, B, D-K, 0.5 mm; C, 0.2 mm.