Denisiella piracurucaensis Silva, Medeiros & Bellini, 2023

Medeiros, Gleyce da Silva, Silva, Clecio Danilo Dias da, Franca, Josemaria Silva de, Godeiro, Nerivania Nunes & Bellini, Bruno Cavalcante, 2023, Two new species of Sminthurididae (Hexapoda, Collembola, Symphypleona) from Brazil with notes on Denisiella Folsom & Mills and Sphaeridia Linnaniemi, ZooKeys 1173, pp. 1-41 : 1

publication ID	https://dx.doi.org/10.3897/zookeys.1173.106855
publication LSID	lsid:zoobank.org:pub:63FA59EA-95EF-4683-B737-802E6AE01034
persistent identifier	https://treatment.plazi.org/id/69CFC9F2-DEF3-49DD-B7D1-8DF387F315B1
taxon LSID	lsid:zoobank.org:act:69CFC9F2-DEF3-49DD-B7D1-8DF387F315B1
treatment provided by	ZooKeys by Pensoft
scientific name	Denisiella piracurucaensis Silva, Medeiros & Bellini
status	sp. nov.

Treatment

Denisiella piracurucaensis Silva, Medeiros & Bellini sp. nov.

Figs 14 View Figure 14 , 15 View Figure 15 , 16 View Figure 16 , 17 View Figure 17 , 18 View Figure 18

Type material.

Holotype: male on slide, Brazil, Piauí state, Piracuruca municipality, Sete Cidades National Park, 'Primeira Cidade’ (4°05'42.53"S, 41°40'50.7"W), 168 m, in sandy soil, ecotonal zone between Caatinga and Cerrado biomes, 14/V/2021, A.M.N. Silva col., pitfall traps. Paratypes three males and four females on slides.

Diagnosis.

Male head and trunk uniformly dark purplish, legs, furca and antennal bases pale, distal Ant I and Ant II-IV purplish (Fig. 14A View Figure 14 ). Male Ant II with 11, Ant III with seven long blunt sensilla, respectively, Tra3 as a regular chaeta, Ant IV with 19 sensilla. Female Ant II and Ant III with spiniform chaetae, Ant IV with eight sensilla. Eyes 8+8. Frontal head with acuminate spiniform chaetae, longer in the females (Fig. 14B View Figure 14 ). Nasal organ absent. Female anal valves with ps2, pi1 and pi3 as barbulated chaetae (Fig. 14C View Figure 14 ). Parafurcal area with 10 chaetae in both sexes. Each tenaculum ramus with three teeth, corpus with 1+1 chaetae (Fig. 14D View Figure 14 ). Males with four campaniform chaetae on the proximal tibiotarsal organ in leg I. Polycarinate chaeta on tibiotarsus II absent. Tibiotarsus III chaetae IIpi, IIIpi, IVpi, and Vpi serrated (Fig. 14E View Figure 14 ). Dorsal dens J chaetae enlarged at their bases, somewhat spiniform, ventral chaetotaxy formula from the apex to the basis as 3,3,3,3,2,1,1,1 or 3,3,3,3,2,1 … 1.

Description.

Body (head + trunk) length of the type series ranging between 0.41 and 1.4 µm, holotype with 0.5 µm, male average size = 0.52 µm, females average size = 1.1 µm, entire type series average size = 0.85 µm. Male head and trunk uniformly dark purplish, legs, furca and antennal bases pale, distal Ant I and Ant II-IV purplish (Fig. 14A View Figure 14 ). Female color pattern unknown (studied specimens already on glass slides).

Head (Figs 15 View Figure 15 - 16 View Figure 16 ). Antennae length: 0.32 µm in the holotype. Holotype antennal segments ratio I:II:III:IV as 1.0:1.1:0.5:1.6. Male antenna: Ant I elongated with seven chaetae, two smaller at the apex, two other apical chaetae thicker than the others (Fig. 15A View Figure 15 ). Ant II with 11 regular chaetae, 11 long blunt sensilla, two bothriotricha (Tra1, Tra2), one microsensillum, modified chaetae b1, b3 and b6 on the anterior tubercle, b2, b4 and b5 on the posterior tubercle, b7 thick, apically flattened and granulated (Fig. 15B View Figure 15 ). Ant III with eight regular chaetae, one of them as a bifurcated chaeta in one antenna of a single specimen, seven long blunt sensilla, three microsensilla, Tra3 as a regular chaeta, apical organ sensory rods in one single shallow invagination, modified chaetae c1 - 3 present, c1 thick, apically flattened, and grainy, c2 as a small blunt projection and c3 as a thick smooth spine in a papilla with at least one cuticular spine between c1 and c3 (Fig. 15C View Figure 15 ). Ant IV with ~ 58 regular chaetae, plus 19 blunt sensilla (Fig. 15D View Figure 15 ). Female antenna: Ant I short with seven chaetae, two smaller at the apex, two other apical chaetae thicker than the others (Fig. 15E View Figure 15 ). Ant II with 12 chaetae (Fig. 15F View Figure 15 ), five of them regular, seven somewhat spiniform. Ant III with 13 chaetae, six of them somewhat spiniform, plus one apical microsensillum; apical organ sensory rods in a single invagination (Fig. 15G View Figure 15 ). Ant IV longer than Ant III, with ~ 52 regular chaetae, plus eight blunt sensilla (Fig. 15H View Figure 15 ). Head capsule (both sexes): Eyes 8+8, with two interocular chaetae, head capsule normal (not elongated) (Fig. 16A, B View Figure 16 ). Clypeal area a-f lines with 8/6/5/4-5/6/6 chaetae, respectively. Interantennal area α and β lines with 2/1 chaetae, respectively; frontal area A-E lines with 2/1/1/1/2 chaetae, respectively, frontal spiniform chaetae of females longer than in the males (Fig. 16A-C View Figure 16 ). Labial basomedian field with four chaetae, basolateral field with five (Fig. 16C View Figure 16 ). Six prelabral chaetae long and thick (Fig. 16A, B View Figure 16 ); labral p, m, and a lines with 5/5/4 thick chaetae, respectively; each a line chaeta in a single papilla; labral papillae present as small spines, labral apex cuticle with six pointed projections (Fig. 16D View Figure 16 ). Mandibles normal (not elongated), with 4+4 incisive apical teeth (Fig. 16E View Figure 16 ). Maxillae normal (not elongated) (Fig. 16F View Figure 16 ). Labrum, labium, and mouthparts without any clear sexual dimorphism.

Trunk (Fig. 17 View Figure 17 ). Large abdomen: thorax continuous with the abdomen, without clear segmentations in both sexes (Fig. 17A, B View Figure 17 ). Male: Th II with one a and one m chaetae; Th III with two a and three m chaetae; Abd I without chaetae; Abd II with bothriotricha A, B, and C misaligned, with two a, two m, and two p regular chaetae; Abd III-IV with three main lines of chaetae above the bothriotrichum B: dI-1 with four, dII-1 with two, dIII-1 with three chaetae respectively, plus seven chaetae below the bothriotrichum B (Fig. 17A View Figure 17 ). Parafurcal area in males with 10 chaetae in four rows of chaetae, with three, two, three, and two chaetae, respectively, neosminthuroid chaetae absent (Fig. 17B View Figure 17 ). Female: Th II with one a and one m chaetae; Th III with two a and two m chaetae; Abd I without chaetae; Abd II with bothriotricha A, B, and C misaligned, with two a, three m, and two p regular chaetae; Abd III-IV with four main lines of chaetae above the bothriotrichum B: dI-1 with eight, dII-1 with seven, dIII-1 with three and dIV-1 with three respectively, plus seven chaetae below the bothriotrichum B. Dorsal chaetae longer than in the males (Figs 14B View Figure 14 , 17C View Figure 17 ). Parafurcal area in females with 10 chaetae in four rows, with three, two, three, and two chaetae, respectively, three internal somewhat spiniform (Fig. 17D View Figure 17 ). Small abdomen: including Abd V-VI in both sexes (Fig. 17E, F View Figure 17 ). Male: Abd V with bothriotricha D and E. Dorsal anal valve with as1-3, ms1-3, mps1, and ps1-2 chaetae, ps2 barbulated; as1, ms1, and ps1 unpaired; each ventral anal valve with aai1-2, ai1-3, ami1 (as an oval organ lacking any inner sensillum), mi1-5, mpi1 and pi1-3 chaetae, pi1 barbulated (Fig. 17E View Figure 17 ). Female: Abd V with bothriotricha D and E present. Dorsal anal valve with as1-3, ms1-4, mps1, and ps1-2 chaetae, ps2 barbulated (Fig. 17F View Figure 17 ); as1, ms1, and ps1 unpaired; each ventral anal valve with aai1-5, ai1-3, ami1 (as an oval organ lacking any inner sensillum), mi1-5, mpi1 and pi1-3 chaetae present, pi1 and pi3 barbulated (Figs 14C View Figure 14 , 17F View Figure 17 ). Genital plate unclear in both sexes.

Abdominal appendages (Fig. 18A, B View Figure 18 ). Ventral tube with 1+1 chaetae. Each tenaculum ramus with three teeth plus an apically rounded basal appendix, corpus with 1+1 chaetae (Fig. 14D View Figure 14 ). Manubrium with 8+8 dorsal chaetae. Dens with a basal appendage and 46 dorsal (posterior) chaetae, lines E/PE/P/JP/JPJ/J with 4/9/10/12/5/6 chaetae, respectively; J line chaetae enlarged at their bases, somewhat spiniform (Fig. 18A View Figure 18 ); dens ventrally (anteriorly) with 17 chaetae, following the formula from the apex to the basis: 3,3,3,3,2,1,1,1 or 3,3,3,3,2,1 … 1 (Fig. 18B View Figure 18 ). Mucro narrow, with an external lamella smooth and an internal lamella serrated with ~ 22 teeth, mucronal chaeta present (Fig. 18A View Figure 18 ). Furca without any clear sexual dimorphism. Manubrium:dens:mucro ratio of the holotype = 1.0:2.5:0.76.

Legs (Fig. 18C-E View Figure 18 ). Leg I: epicoxa and subcoxa without chaetae, coxa with one chaeta; trochanter with three chaetae; femur with 11 chaetae, two of them curved; tibiotarsus with 36 chaetae and two oval organs (O2pe, O2ae), whorls I/II/III/IV/V with 9/8/7/7/5 chaetae respectively, chaeta IIpi serrated; male proximal four chaetae IVe, IVae, Ve, and Vae modified into campaniform sensilla (Fig. 18C View Figure 18 ). Leg II: epicoxa with one chaeta, subcoxa without chaetae, coxa with one chaeta; trochanter with three chaetae; femur with 12 chaetae; tibiotarsus with 37 chaetae and two oval organs (O2pe, O2ae), whorls I/II/III/IV/V with 9/8/7/7/6 chaetae respectively (Fig. 18D View Figure 18 ). Leg III: epicoxa with one chaeta, subcoxa with one chaeta, coxa with three chaetae (two regular and one small); trochanter with three chaetae; femur with 11 chaetae, one of them curved; tibiotarsus with 38 chaetae and two oval organs (O2pe, O2ae), whorls I/II/III/IV/V with 9/8/8/7/6 chaetae respectively; chaetae IIpi, IIIpi, IVpi, and Vpi serrated (Figs 14E View Figure 14 , 18E View Figure 18 ). Oval organs of all tibiotarsi in both sexes with a tiny inner sensillum, each (not represented in the figures). Foot complexes: pretarsi I-III with an anterior and a posterior chaetae each; ungues I-III subequal in shape, with one dorsal unpaired tooth, a pair of basal lateral teeth and one medial internal tooth; unguiculi I-III somewhat truncate, without teeth, with all lamellae smooth. Female unguiculi apical filament surpassing the apex of the ungues in legs I-III; male unguiculi apical filament surpassing the apex of the ungues in legs I and II, unguiculus III apical filament absent or reduced in leg III; ratio of ungues I-III in the holotype = 1.0:0.9:0.8.

Etymology.

The species was named after its type locality, Piracuruca municipality, Piauí state, Brazil.

Remarks.

As said before, D. piracurucaensis sp. nov. belongs to the Denisiella seurati group due to the absence of the nasal organ on males. Within this group, it is more similar to D. betschi , D. colombiana , D. maesorum and D. rhizophorae due to the presence four serrated spines on the tibiotarsus III. It looks more similar to D. colombiana by the presence of spiniform chaetae at least on Ant II of the female and a similar ventral dens chaetotaxy. Even so, the new species can be separated from all of these taxa especially by the presence of 8+8 eyes (6+6 in the other species), ps1 and pi1 as barbulated chaetae on the male anal valves (both regular chaetae in D. betschi and D. rhizophorae , only pi1 and pi3 as barbulated chaetae in D. colombiana ), and the absence of a polycarinate chaeta on the male tibiotarsus II (present in D. betschi , D. colombiana , and D. rhizophorae ). Further comparisons are presented in Table 2 View Table 2 .