Coarazuphium bambui, Pellegrini & Bichuette & Vieira, 2022

Pellegrini, Thais Giovannini, Bichuette, Maria Elina & Vieira, Letícia, 2022, Coarazuphium bambui (Carabidae: Zuphiini), a new cave-dwelling beetle from the threatened region of Serra do Ramalho, Brazil, Zootaxa 5129 (4), pp. 557-568 : 560-561

Coarazuphium bambui sp. n. Pellegrini & Vieira

( Figs. 5-16 )

Holotype: BRAZIL, 1 ♂, Bahia state, Feira da Lapa municipality, Gruna Boca da Lapa cave ; 13° 56' 46" S, 44° 11' 12" W; 15 Oct 2020; L. Senna-Horta, M.E. Bichuette, J.E. Gallão leg.; MZSP —46489. Remarks: genitalia dissected . Paratype: BRAZIL, 1 ♀, Bahia state, Feira da Lapa municipality, Gruna Boca da Lapa cave; Lat 13° 56' 46" S: Lng 44° 11' 12" W; 15 Oct 2020; L. Senna-Horta, M.E. Bichuette, J.E. Gallão leg.; CEUFLA COL 0000002 . Remarks: The paratype had its abdomen and elytra removed for genital dissection and description of the posterior wings, respectively .

Type locality. The specimen is known from a single cave, the Gruna Boca da Lapa cave, with approximately 3 km of development, the cave is located in the municipality of Feira da Lapa in the state of Bahia, Brazil ( Figs. 1-4 ).

Diagnosis. All characteristics of C. bambui sp. n. are consistent with the description of the genus Coarazuphium . This species differs from all others of the genus by the following combination of characters: elytra with almost parallel sides with maximum width in the posterior half; elytra with an apical margin with a slight sinuosity; fixed setae from head dorsally: one pair of anterior supraorbital setae (asos), one pair of postocular setae (pos) and one pair of posterior supraorbital setae (psos); antennae long, about 0.93 times of body length; metafemur without a spine at the middle ventral side; Median lobe of aedeagus about 2.39 times longer than left paramere and 6.34 times longer than right paramere.

Description. Size and proportions. ( Fig. 6 ). OBL: 4.50 mm ♂ and 4.53 mm ♀; EW: 1.57 mm ♂ and 1.47 mm ♀; HW/PW: 0.95 ♂ and 1.00 ♀. Body uniformly of orange color. Dorsal integument covered with short recumbent hairs.

Head. Subtrapezoidal ( Fig. 6 ), HW/HL: 0.78 ♂ and 0.82 ♀. Head almost as wide as pronotum. Fixed setae disposition on the dorsal part of the head: an anterior pair of supraorbital (asos) above eyes; one pair of postocular (pos) immediately behind eyes, laterally; and one pair of posterior supraorbital setae (psos) ( Fig. 1 ); ventrally, in the gena are four pairs of setae; two pairs are close to the gular region; one pair is located medially; and the fourth is the bigger one and is located close to the submentum, more laterally. Eyes reduced, depigmented, and flattened, situated laterally at the end of the genal sulcus (gs), ommatidia are not evident at 50x ( Fig. 5 ). Antennae long, filiform and flagellar, ( Fig. 6 ) AL: 4.60 mm ♂ and 4.26 ♀; AL/PL: 5.50 ♂ and 5.07 ♀; A1L/A2-4L: 0.78 ♂ and 0.84 ♀, with almost the same length. First antennomere (scape) with a long seta distally close to the apical portion, and a row of several semi-erect setae; 2nd very short. Segments 3rd-10th subequal, elongated, and almost round in cross-section, except for the tip of the terminal antennomere, which is laterally flattened.

Pronotum. Shape trapezoidal, PL/PW: 0.91 ♂ and 0.93 ♀ ( Fig. 6 ). Maximum width close to anterior angle, which is almost as wide as head. Anterior angle rounded. Posterior angle acute. Dorsal surface with two pairs of lateral marginal erect setae: one longer close to the antero-lateral angles and the other shorter, close to the posterolateral angles. Ventral surface with one pair of anterior setae medially located ( Fig. 8 ).

Pterothorax. Metasternum wider than long; metepisternum longer than wide.

Elytra and hind wings. Elytra are free, not fused ( Fig. 6 ), EL/EW: 1.63 ♂ and 1.75 ♀. Elytra with almost parallel sides with the maximum width in the posterior third, EW/PW: 1.71 ♂ and 1.62 ♀. Apex of elytra with a slight sinuosity. Elytral chaetotaxy: no discal setae present; umbilicate series of the 8th stria with seven large setae on each elytron: 3 close to the anterior angle, 2 marginal in lateral posterior half, and 2 on posterior margin (some of these setae are missing, but it is possible to see their insertion). Hind wings reduced, not functional, folded in a Z-shape, like the bellows of an accordion ( Fig. 7 ), 0.65 mm ♀ long, HWL/EL = 0.25.

Abdomen. Abdominal tergites 1-6 with a very fine pubescence, tergites 3-6 with a pair of small setae located medially on the posterior half, sixth sternite with a pair of ventral setae at its posterior margin.

Legs. Profemur 1.07 ♂ and 1.03 ♀ times longer than the mesofemur and 0.77 ♂ and 0.71 ♀ times the length of metafemur. Protibia 1.02 ♂ and 1.04 ♀ times longer than the mesotibia and 0.74 ♂ and 0.74 ♀ times the length of metatibia. Protibia 1.44 ♂ and 1.27 ♀ times longer than protarsus. Mesotibia 0.88 ♂ and 0.95 ♀ times the length of mesotarsus and metatibia 1.00 ♂ and 1.09 ♀ times the metatarsus. First tarsomere from pro-, meso-, and metatarsus almost equal to tarsomeres 2-4 together. Length of protibia and tarsus together 2.15 ♂ and 2.18 ♀ times the length of the pronotum. Mesotibia and tarsus length 2.45 ♂ and 2.40 ♀ times, and metatibia and tarsus length 3.40 ♂ and 3.15 ♀ times the length of pronotum.

Aedeagus. Phallus slightly curved ventrally and elongate, apically narrowed and flattened dorsoventrally, apical margin rounded ( Figs. 11-13 ), PHL = 0.98 mm; OML = 0.29 mm. Left paramere subtriangular, conchoid, about 4 times longer than wide, LPL = 0.41 mm; right paramere broad, conchoid, distinctly shorter than left paramere, RPL = 0.15 mm. Male genital segment oval shaped, GSL = 1.15 mm; twice longer as wide ( Figs. 9-10 ).

Female reproductive tract. Ovipositor ( Figs. 14-16 ): with a broad laterotergite (lt); basal gonocoxite 1 (gc1) longer than apical gonocoxite 2 (gc2), with four long trichoid setae apicoventrally and one in the inner apicolaterally border, in addition to two median trichoid setae, one of these bifurcated, and one small trichoid setae apicodorsally; gonocoxite 2 strongly curved, falciform in lateral aspect, slightly rounded apex; circuloid preapical setose organ (pso) on the inner concave face, with four nematiform setae, the surface of gonocoxite 2 with many marginal pit pegs (mpp) apically as well as medially ( Fig. 16 ). Female genital tract membranous except for the helminthoid sclerite (hs) ( Fig. 14 ); bursa copulatrix (bc) elongated, length more than twice the circumference, which continues in the bursal saculus (bs) anterior to the point of insertion of the common oviduct (co), which makes a slight curve to the right side basally. Spermatheca (sp) long starting near the junction of the common oviduct, spermatheca is markedly elongated, becoming slender and winding distally; at the junction of the common oviduct at the base of the spermatheca, the helminthoid sclerite (hs) is present, it is rounded and globet-shape ( Fig. 15 ). Spermathecal gland and its duct were broken and were not represented or visualized. No secondary spermathecal gland.

Etymology. The specific epithet bambui is in honor of the Grupo Bambuí de Pesquisas Espeleológicas (GBPE), which historically contributed to the knowledge of Brazilian caves in the last 38 years, shared this knowledge and also discovered this unique cave, the Gruna Boca da Lapa. This epithet name also refers to the geomorphological group in which the cave is inserted, the Bambuí Group formation.

Distribution, habitat, and ecological notes. Only known from the type locality. BRAZIL, Bahia: Feira da Lapa municipality, Gruna Boca da Lapa cave ( Figs. 1-4 ).

The Serra do Ramalho karst area is located southwest of the Bahia state and is part of the Bambuí Geomorphological group ( Fig. 1A ). The region holds dozens of caves ( Rubbioli et al. 2019). According to Köppen criteria, the region has a tropical dry climate (=semiarid) (“Aw”), with annual precipitation of about 640 mm and subterranean waters with anthropic use mainly for consumption ( Belda et al. 2014). The surrounding vegetation consists of a Tropical Dry Forest, composed of mesophytic and xeromorphic forests interspersed with semideciduous forests species ( Fig. 1C ).

This karst area should be highlighted, as in addition to housing cave type locality of the new species, it is the location of the Aguas Claras Cave System, recently considered the third hotspot of subterranean biodiversity in South America ( Souza-Silva et al. 2021). However, these areas are threatened by anthropogenic impacts, mainly due to agricultural pressure and future concessions for mining activities ( Fig. 1 ). It is essential to highlight that mining concessions are growing in Brazil and this economic activity have a high potential for cave habitats destruction ( Gallão & Bichuette 2018; Gomes et al. 2019).

The cave environment where Coarazuphium bambui sp. n. occurs is characterized by a highly humid habitat. Specimens were found associated with the riverbank in the aphotic zone ( Figures 2 and 4 ). The cave substrate in the region of C. bambui sp. n. occurrences are mainly composed of silt, pebbles, and rocks ( Figure 3 ). The specimens were active, with fast-locomotor behavior. The individuals are indifferent to the lantern flashlights (ca. 600 lumens of intensity), with no photophobic behavior.

Figures

FIGURE 1. Geographic localization of all described Coarazuphium species including the Coarazuphium bambui sp. n. at its type locality (Gruna Boca da Lapa Cave), it is also show the Tropical Dryforest ecosystems, the limestone outcrops of the Bambui Supergroup, highlighting the state of Bahia, northeastern Brazil. A. Mining pressures related to future projects in the region; B. Impacts close to Gruna Boca da Lapa cave related to agriculture activities.

FIGURES 2-4. Gruna Boca da Lapa cave 2. Entrance of the type locality cave. 3. Details on the microhabitat where specimens of C. bambui sp. n. were found, substrate composed of pebbles, silt, and rock. 4. Gruna Boca da Lapa cave gallery showing the large river channel and the river banks. (Photographs 2-4 are from A. Lobo).

FIGURES 5-8. Coarazuphium bambui sp. n., male holotype. 5. Head, pronotum and prothorax, lateral view; Scale bar = 0.2 mm. 6. Habitus dorsal view; Scale bar = 1.0 mm. 7. Detail on hindwings; Scale bar = 0.2 mm. 8. Prothorax, ventral view; Scale bar = 0.2 mm.

FIGURES 9-13. Coarazuphium bambui sp. n. male holotype. 9-10. Genital segment capsule; Scale bar = 0.2 mm. 11. Aedeagus left view; 12. Aedeagus dorsal view; 13. Aedeagus right view; Scale bar = 0.2 mm.

FIGURES 14-16. Coarazuphium bambui sp. n. female paratype. 14. Female genital reproductive tract, ventral view; Scale bar = 0.2 mm. 15. Detail on helminthoid sclerite; Scale bar = 125 μm. 16. Left gonocoxites ventral view, showing detail on preapical setose organ; Scale bar = 125 μm. Legend: (bc) bursa copulatrix; (bs) bursal sacculus; (co) common oviduct; (sp) spermatheca; (hs) helminthoid sclerite; (gc1): gonocoxite 1; (gc2): gonocoxite 2; (lt): laterotergite; (pso): preapical setose organ; (mpp) marginal pit pegs.