Itararecarcinia yapyra, Cardoso & Bento & Ferreira, 2025

Cardoso, Giovanna Monticelli, Bento, Diego de Medeiros & Ferreira, Rodrigo Lopes, 2025, Remnants of an ancient world: three new genera and three new species of Calabozoidea isopods from Brazilian semi-arid caves (Crustacea: Isopoda), Tropical Zoology (trop. Zool.) 38 (1 - 2), pp. 1-25 : 9-16

publication ID	https://doi.org/10.4081/tz.2025.180
publication LSID	lsid:zoobank.org:pub:A3B5E8FB-4BEC-48E7-8F5F-AEEE16D194B9
DOI	https://doi.org/10.5281/zenodo.15787448
persistent identifier	https://treatment.plazi.org/id/B5213824-FFE0-FFA5-FE35-FAE2C027091F
treatment provided by	Felipe
scientific name	Itararecarcinia yapyra
status	sp. nov.

Treatment

Itararecarcinia yapyra n. sp.

Figures 5–9 View Figure 5 View Figure 6 View Figure 7 View Figure 8 View Figure 9 , 10A–C View Figure 10 , 14B View Figure 14

urn:lsid:zoobank.org:act:4B851EEC-53A1-49E9-8962-2E09009DC7A5

Material examined

BRAZIL: Holotype ♂ ( ISLA96927 ), Rio Grande do Norte state, Governador Dix-Sept Rosado municipality, Olho d’água da Gangorrinha cave (5.48074°S, 37.54165°W), leg. RLF and DMB GoogleMaps . Paratypes: 2 ♂♂ (1 ♂ in slide), 7 ♀♀ ( ISLA 96928 ) , 3.IV.2024; 3 ♀♀ ( ISLA 96922 ), 4.VI.2021; 4 ♀♀ ( ISLA 96923 ), 11.VII.2021; 8 ♀♀ (1 ♀ on slide) ( ISLA 96924 ), GoogleMaps 23.V.2023, same locality as holotype. 1 ♂ ( ISLA 96921 ) GoogleMaps , 2 ♂♂ in slides, 8 ♀♀ ( ISLA 848 ) , 1 ♂, 6 ♀♀ ( ISLA865 ), RN state, Governador Dix-Sept Rosado municipality, Poço Feio cave (5.48768°S, 37.55927°W), 20.VII.2010, leg. RLF GoogleMaps .

Description

Body approximately 1.6 mm, four times as long as wide ( Figures 5A View Figure 5 , 13G View Figure 13 , 14C View Figure 14 ). Head shield with clypeus short; eyes absent. Pereonites rectangular, with round epimeral angles and four setae on lateral margins, pereonite III widest ( Figure 13G View Figure 13 ). Pleon ( Figures 5A View Figure 5 , 13G View Figure 13 ) length about 35% of body length; pleonites I–II reduced, pleonites I and III width about 60% and 80% of pereonite VII width, pleonites III – V with two setae laterally. Pleotelson ( Figures 5A View Figure 5 , 10C View Figure 10 ) approximately 20% of body length, and 60% of pleon length, longer than wide, with seven to nine setae on lateral margin and six setae on apex. Antennula ( Figure 5B View Figure 5 ) shorter than peduncle of antenna, flagellum of one article with one aesthetasc, 1.5 longer than flagellum. Antenna ( Figure 5B View Figure 5 ) long, about 50% of body length, reaching pereonite IV, flagellum with 11 articles. Left mandible ( Figure 5D View Figure 5 ) incisor with four teeth, lacinia mobilis with denticulate apex; right mandible ( Figure 5E View Figure 5 ) incisor with three teeth, lacinia mobilis bifid. Maxillula ( Figure 5F View Figure 5 ) lateral lobe with seven robust simple setae, two robust serrate setae and one trifid seta medially, mesial lobe with three robust pappose setae. Maxilla ( Figure 5G View Figure 5 ) lateral and medial lobe with nine serrate setae each; mesial lobe with four plumose setae and three simple setae. Maxilliped ( Figure 5H View Figure 5 ) endite proximal lobe with seven pappose setae apically, distal lobe with eight pappose setae; palp of five articles, first article fused with maxilliped body, articles with long simple setae, article 5 smallest, with tuft of distal setae. Pereopod I ( Figures 6A View Figure 6 , 10D View Figure 10 ) ambulatory, carpus one third of propodus length, propodus medial margin with three serrate setae, dactylus longer than propodus, unguis shorter than dactylus; propodus and unguis lateral margin with scales. Pereopod II ( Figure 6B View Figure 6 ) carpus slightly shorter than propodus, distal margin with one long plumose seta, dactylus shorter than propodus, dactylus and unguis inner margin with scales. Pereopods III –VII progressively growing in length. Pereopod VII ( Figure 6C View Figure 6 ) two times longer than pereopod I, propodus 1.5 longer than carpus, carpus distal dorsal margin with one long plumose seta, unguis as long as dactylus. Uropods ( Figure 6D View Figure 6 ) reduced, not exceeding pleotelson apex, uniramous, stout, 15% of pleotelson length.

Mature male. Genital papilla ( Figure 6D View Figure 6 ) with bilobed. Pleopod I ( Figure 6D View Figure 6 ) simple, styliform, apex tapering, directed outward. Pleopod II ( Figure 6D View Figure 6 ) endopodite long and simple, exopodite longer than wide, apex with two plumose setae. Pleopods III – V exopod round, longer than wide, with two plumose setae inserted paradistally on medial margin, similar in shape.

Female. Pleopod I ( Figure 6E View Figure 6 ) endopodite longer than wide, apex with two plumose setae. Pleopod II ( Figure 6E View Figure 6 ) protopodite trapezoidal, endopodite article with one plumose seta apically, exopodite oval shaped with two plumose setae on lateral margin.

Paratypes from Poço Feio cave. Immature male body with 1.2 mm ( Figure 7A View Figure 7 ). Antenna with 11 articles ( Figure 7B View Figure 7 ). Genital papilla weakly developed. Pleopod I ( Figure 7C View Figure 7 ) longer than wide with two plumose setae apically. Pleopod II ( Figure 7C View Figure 7 ) inner ramus weakly developed, simple, with round outer ramus. Uropods ( Figure 7A View Figure 7 ) weakly developed, not exceeding pleotelson apex. Mature male with pleopod I and II similar to holotype ( Figure 7D,E View Figure 7 ).

Etymology

The term “yapyra ” originates from the Brazilian Indigenous Tupi language, meaning “headwater” or “a river spring.” This designation is inspired by the caves where the species was discovered, characterized as a karst resurgence.

Habitat, threats and conservation status

Specimens of I. yapyra n. sp. were collected in the Olho D’Água da Gangorrinha cave and the Poço Feio cave ( Figures 1 View Figure 1 , 8 View Figure 8 , 9 View Figure 9 ), both corresponding to karst resurgences situated on the banks of the Apodi-Mossoró River, however, on opposite margins of the river. The water flowing from both resurgences directly meets the river watercourse.

The Olho D’Água da Gangorrinha cave, with a small entrance, is generally accessible throughout the year, except during certain rainy periods when its entrance becomes submerged ( Figure 8C,D View Figure 8 ). This entrance leads to a narrow conduit, allowing entry into the cave for approximately 5 meters. Beyond this point, access to the innermost parts of the cavity is obstructed by several blocks. Despite its modest size, the entrance allows light to penetrate, ensuring there are no completely dark areas within the accessible region. Along the walls, large tufts of roots from external vegetation thrive, providing a protected habitat and organic resources for the fauna inhabiting them. These roots may also offer protection against predation from epigean fish that enter the cave. Specimens of I. yapyra n. sp. were discovered within the submerged root masses and were collected using a zooplankton net ( Figure 8E,F View Figure 8 ). During sampling, the roots were carefully examined by snorkeling, revealing no specimens of I. yapyra n. sp. in the surrounding areas, indicating their sheltered location deep inside. The roots were then vigorously shaken to remove all small invertebrates. Physicochemical parameters of this drainage were measured during six visits to the cave between November 2021 and August 2023, revealing the following characteristics: water temperature: 32.33±0.24°C; pH: 6.84±0.60; conductivity: 0.94±0.28 µScm-1; dissolved oxygen: 2.07± 1.29mg /l; total dissolved solids: 0.60± 0.18 g /l; total phosphorus: 56.46±15.18 μg/L; total nitrogen: 11.26± 4.20 mg /l; total carbon: 33.97± 14.63 mg /l.

It is important to highlight that several anthropogenic impacts are observed close to this cave. Aside from vegetation removal, limestone burning to produce lime also substantially alters the cave’s surroundings ( Figure 8B View Figure 8 ). Furthermore, given the short distance, the remnants of this burning process may reach the cave, posing an ongoing threat. This is a particular concern since groundwater and karst aquifers are particularly vulnerable to contamination ( Ford and Williams 2007). Lastly, the Olho d’Água da Gangorrinha cave lies within a mining polygon with an allocated mining concession, signaling the potential establishment of a mining project in the near future.

The Poço Feio cave ( Figure 9 View Figure 9 ), a limestone karst resurgence with a substantial flow rate, features a single accessible entrance leading to a small passage connecting to the main conduit 40 meters from the entrance ( Figure 9 View Figure 9 B-D). Water emerges through gaps between blocks, forming a small 1.8 m deep pool. While the water flow rate varies between dry and rainy periods, the water level fluctuations are not significant. Intense rainfall may cause water to overflow the entrance, indicating a considerable rise in water level, but such episodes are rare. Conversely, water flow interruptions are even rarer, occurring only once in the last 20 years, leaving only a few puddles inside and near the resurgence. The entirely submerged conduit poses challenges for accessing deeper sections due to limited airspace. Tufts of roots grow abundantly near the entrance, where specimens of I. yapyra n. sp. were captured using zooplankton nets. Physicochemical parameters were measured during six visits to the cave between 7/13/2021 and 12/08/2023, revealing the following characteristics of this water body: water temperature: 31.22±0.66°C; pH: 7.14±0.21; conductivity: 0.65±0.14 µScm-1; dissolved oxygen: 1.99± 1.59mg /l; total dissolved solids: 0.41± 0.09g /l; total phosphorus: 54.90±22.53μg/L; total nitrogen: 6.97± 6.88mg /l; total carbon: 27.74± 8.35mg /l. It is worth noting that some specimens were collected before the severe drought of 2016. During this drought, which led to the disappearance of the drainage, the roots were exposed, likely resulting in a significant reduction in the population of I. yapyra n. sp., at least in this accessible part of its habitat. Additionally, it is important to emphasize that the pool adjacent to the resurgence is utilized by residents for recreation. Although most visitors remain outdoors, some occasionally venture into the cave and leave organic and inorganic waste there. Thus, disorderly tourism has an anthropogenic impact that affects the cave environment and its fauna.

The surrounding area of the cave has undergone significant alterations, primarily through the removal of native vegetation for agricultural purposes. The native vegetation plays a crucial role in sustaining the diversity of subterranean communities ( Bento et al. 2021). Deforestation can disrupt subsurface hydrological systems and alter the nutrient inputs into the cave, potentially leading to the decline or extinction of endemic species ( Mammola et al. 2019). Additionally, the expansion and intensification of agriculture contribute to increased evapotranspiration ( Destouni et al. 2013), which reduces water runoff and aquifer recharge ( Ceballos et al. 2015). Finally, the Poço Feio cave is situated within a mining polygon earmarked for future mining projects. This impending development suggests that mining activities may potentially commence in the area in the upcoming years.

It is worth noting that this species was discovered in caves located on opposite sides of the Apodi River. This distribution could only occur through two possible scenarios: i) the migration of individuals along the riverbed, leading to the colonization of caves located further downstream, or ii) migration through saturated subterranean passages existing beneath the Apodi Riverbed. Given that the Olho D’Água da Gangorrinha cave is located 2.25 km downstream from the Poço Feio cave, it is improbable for these small crustaceans to reach this cave, considering the abundance of predators in the riverbed. Moreover, even if they were dispersed by the downstream river current, colonizing the Olho D’Água da Gangorrinha would require them to contend with the strong current generated by the significant flow of the cave’s resurgence. Hence, the surface dispersal of these organisms is highly unlikely. Consequently, the existence of underground connections in the saturated zone below the Apodi riverbed is a more plausible explanation. This suggests that the distribution of this species might be far greater than currently understood.

Given that these two caves represent the only known habitats of I. yapyra n. sp., both its Extent of Occurrence ( EOO) and Area of Occupancy ( AOO) are estimated to be less than 100 km ² and 10 km ², respectively. It is reasonable to infer that current and potential impacts on the caves and their surroundings directly affect all species, effectively constituting two sites. These impacts further contribute to a continuous decline in habitat quality. Consequently, I. yapyra n. sp. could be classified as Endangered ( EN) under criteria B1ab(iii)+2ab(iii). Therefore, it is imperative to protect both the cave and its surrounding area and to regulate anthropogenic activities such as agriculture, mining, and recreational use to safeguard this species.