Ctenorillo cearensis 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 : 114-116

Ctenorillo cearensis Cardoso & Ferreira , n. sp.

( Figs 14 ; 15 ; 27F )

urn:lsid:zoobank.org:act:29FFBB09-6896-4C9B-97BE-E50E44C7C180

TYPE MATERIAL. — Holotype. Brazil • 1♂ (4 mm; parts in slide); Ceará state; Santa Quitéria municipality; W_04 cave; 4°33’53”S, 39°46’36”W; Carste leg.; 10-18.III.2021; ISLA 96021.

OTHER MATERIAL. — Brazil • 1 ♂; SQ_26 cave; 4°33’38”S, 39°46’51”W; Carste leg.; 10-18.III.2021; ISLA96020 • 1 ♀; W_16 cave; 4°33’43”S, 39°46’44”W; Carste leg.; 10-18.III.2021; ISLA96026 • 1 ♀; SQ_03 cave; 4°33’53”S, 39°46’40”W; Carste leg.; 10-18.III.2021; ISLA96033 • 2 ♂; SQ_P2 cave; 4°33’37”S, 39°45’57”W; Carste leg.; 10-18.III.2021; ISLA96962 • 3 ♀; SQ_03 cave; 4°34’4”S, 39°47’0”W; Carste leg.; 10-18.III.2021; ISLA96025 .

ETYMOLOGY. — The new species name, “cearensis ”, refers to the people who are born in the State of Ceará, Brazil. The word Ceará comes from the tupy language that means the macaw’s singing (o canto dajanaia in Portuguese).

DIAGNOSIS.— Dorsum covered by weakly developed tubercles and ribs with three rows on cephalon (4, 4, 4); three rows on pereonite 1 (2, 8, 9); two rows on pereonites 2-6 (4 + 11) and on pereonite 7 (4 + 7); one row of four tubercles on pleonites 3-5; and two paramedian tubercles on telson. Pleopod 1 exopod with round distal portion, outer margin straight; endopod with distal portion straight, four times longer than exopod.

DISTRIBUTION. — Santa Quitéria municipality, Ceará state.

DESCRIPTION

Maximum size: ♂ and ♀, 4 mm. Color grey ( Fig. 27F ). Dorsum covered by weakly developed tubercles and ribs ( Fig. 14A, B ): cephalon with three rows (4, 4, and 4 from front to back of vertex); pereonite 1 with 15 in three rows (2, 8 and 9); pereonites 2-6 with 15 (4+11); pereonite 7 with 11 (4 +7); pleonites 3-5 with one row of four tubercles; telson with two paramedian tubercles. Dorsal cuticle with short triangular scale setae; pereonites 1-7 bearing one line of noduli lateralis per side on outer surface of posterior tubercle of second line of tubercle. Cephalon with frontal shield protruding above vertex; eye consisting of eight ommatidia ( Fig. 14C, D ). Pereonite 1 inner lobe of schisma rounded, extending beyond posterior margin of outer lobe; pereonite 2 with triangular ventral tooth reaching posterior margin of epimera ( Fig. 14E ); pereonites 2-7 with wide quadrangular epimera ( Fig. 14A ). Telson ( Fig. 14F ) hourglass-shaped, proximal portion broader than distal portion. Antennula ( Fig. 14G ) of three articles, second article shorter than first and third, third article with six apical aesthetascs. Antenna ( Fig. 14H ) short and stout, flagellum shorter than fifth article of peduncle; second article of flagellum about three times as long as first. Buccal pieces as C. pelado Cardoso & Ferreira , n. sp. ( Fig. 14 I-M). All pleopod exopods with monospiracular covered lungs. Uropod ( Fig. 15A ) protopod flattened, enlarged on basal portion; exopod outward, short, inserted dorsally close to medial margin of protopod.

Male

Pereopods without particular modifications ( Fig. 15B, C ). Pleopod 1 exopod ( Fig. 15D ) wider than long, round distal portion, outer margin straight; endopod with distal portion straight, four times longer than exopod. Pleopod 2 endopod longer than exopod ( Fig. 15E ). Pleopods 3-5 exopods as in Figure 15 F-H.

HABITAT

Specimens of C. cearensis Cardoso & Ferreira , n. sp. were found in six limestone caves inserted in the caatinga biome in northern Ceará state. The region experiences a Tropical Hot Semi-arid climate (BSh according to Koppen), with an average annual rainfall of 799.8 mm concentrated between February and April ( Álvares et al. 2013). Average temperatures in the region hover around 27°C, with approximately 3°C of thermal amplitude ( IPECE 2011). The area features three types of vegetation: Tropical Steppe, located in both the residual massifs and dissected areas of the Sertaneja Depression; Thorny Deciduous Forest and Tropical Rainforest. Unfortunately, the biologists who collected the specimens did not provide any data on the caves or the conservation status of the surrounding region. However, at least 74 caves were inventoried in the region, and specimens of C. cearensis Cardoso & Ferreira , n. sp. were found only in six of them. As mentioned for other species herein described, external inventories were not conducted, hence it is not possible to determine the actual distribution of this species. Nonetheless, the species does not present any troglomorphic traits, which would suggest its restriction to subterranean habitats. Importantly, the cave inventories were conducted to rank the importance of the caves in the area, as required by Brazilian environmental agencies for evaluating projects that may impact the environment. The potential installation of quarries in the area is a cause for concern since the limestone caves in the region are located close to uranium deposits ( Júnior & de Souza 2012), and such enterprises could destroy the caves where the species occurs and severely alter the surrounding external habitats.

REMARKS

As C. ubajarensis Cardoso & Ferreira , n. sp., C. cearensis Cardoso & Ferreira , n. sp. presents the less developed tubercles, however the tubercles are more prominent than in C. cearensis Cardoso & Ferreira , n. sp. As the other Brazilian species, C. cearensis Cardoso & Ferreira , n. sp. presents the pleonites 3-5 with four tubercles each and differs from them by the number of tubercles on pereon, with 19 tubercles on pereonite 1, 15 on pereonites 2-6, and 11 on pereonite 7.

Figures

FIG. 14. — Ctenorillo cearensis Cardoso & Ferreira,n. sp.,holotype (male,4 mm,ISLA96021):A, habitus,lateral view;B, disposition of dorsal tubercles;C, cephalon, frontal view; D, cephalon, dorsal view; E, epimera 1-3 ventral view; F, pleonites 3-5, uropods and telson, dorsal view; G, antennula; H, antenna; I, right mandible; J, left mandible; K, maxillula; L, maxilla; M, maxilliped. Scale bar: 0.5 mm.

FIG. 15. — Ctenorillo cearensis Cardoso & Ferreira,n. sp., paratype (male, 4 mm, ISLA96021):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. 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.