Szeptyckitheca cyanea Oliveira, Medeiros & Bellini, 2023

Bellini, Bruno Cavalcante, Oliveira, Mariana Fernandes De, Weiner, Wanda Maria, Nunes, Rudy Camilo & Medeiros, Gleyce Da Silva, 2023, Revisiting Szeptyckitheca Betsch & Weiner (Collembola, Symphypleona, Sminthuridae): new species, updated diagnoses, and a key, ZooKeys 1186, pp. 139-174 : 139

Szeptyckitheca cyanea Oliveira, Medeiros & Bellini sp. nov.

Figs 7 , 8 , 9 , 10 , 11

Type material.

Holotype male on slide, Brazil, Rio Grande do Norte state, Nísia Floresta municipality, "Floresta Nacional de Nísia Floresta" (6°5'9.132"S, 35°10'53.857"W), 02/VI/2022, Xavier M.D. col., pitfall traps. Paratypes on slides: one male and one female, with the same data as the holotype.

Other examined material.

Two males and one female on slides, Brazil, Rio Grande do Norte state, Natal municipality, "Mata da CAERN - UFRN" (5°50'9.665"S, 35°12'12.953"W) .

Diagnosis.

Specimens mostly bluish. Ant. IV with 11 subsegments, with at least six capitate chaetae; Ant. III with 21 chaetae other than the sensory clubs, including two peculiar small sensilla within cavities; Ant. II undivided, with 15 chaetae, four of them slightly longer than the others; Ant. I with six chaetae. Eyepatches with two small interocular chaetae. Head vertex with a total of 18 large spines, two of them unpaired; unpaired chaeta A1 present and regular (not spine-like); secondarily reduced chaetae near the spines absent. Trochanters I-III with 2,1,1 spines, respectively, trochanters I and II spines capitate, III blunt; trochanter III with five regular chaetae other than the spine. Ungues with a one inner tooth, with tunica and weak pseudonychia; unguiculus I with the internal tooth; unguiculus III filament thin and not reaching the tip of the unguis III. Large abdomen dorsally with ~ 26+26 long capitate mac. Female with a long subanal appendage (surpassing the apex of the ventral anal valves), slightly curved at the apex, acuminate, and apically serrated on its internal face. Manubrium with 7+7 dorsal chaetae; dens ventral chaetotaxy formula from the apex to the base as: 3,2 … 1, dorsal chaetotaxy with 16 chaetae; mucronal notch prominent.

Description.

Body (head + trunk) length of the type series ranging between 551 and 818 µm, holotype with 624 µm, males’ average size = 588 µm, females’ average size = 818 µm, entire type series’ average size = 664.5 µm. Specimens entirely dark bluish (Fig. 7 ).

Head (Fig. 8 ). Antennae length 445.4 µm in the holotype. Holotype antennal segment ratio I:II:III:IV as 1:1.3:2.3:5.2. Ant. IV with 11 subsegments, subsegment I with two or three, II with four, III with three or four, IV with five or six, V with eight, VI-X with ten each, and XI with ~ 19 chaetae, respectively, subsegments I+II with six or seven capitate chaetae (Fig. 8A ). Ant. III with 21 chaetae other than the sensory clubs, including two peculiar small sensilla within cavities and one small sensillum without cavity, regular chaetae sizes variable but none remarkably longer than the others, most chaetae capitate, sensory rods inside two separate shallow cavities (Fig. 8B ). Ant. II undivided, with 15 capitate chaetae, four of them slightly longer than the others (Fig. 8B ). Ant. I with six chaetae, one of them ventral (Fig. 8B ). Eyes 8+8, with 2+2 small interocular chaetae, head capsule normal (not elongated) (Fig. 8C ). Clypeal area a - f lines with 7-8/7/5/6/5(+1)/3 dorsal + ventral chaetae, respectively, e1 chaeta present, zones without cuticular granulation and oval organs only seen in the ventral side (Fig. 8C, D ). Interantennal area α and γ lines with 1/2 regular chaetae, respectively; frontal area A - E lines with a total of 18 large smooth spines, chaetotaxy following the formula: 1(+1)/2/1(+1)/2(+1)/3, respectively, without secondarily reduced spines, A1 chaeta present (Fig. 8C ). Labial basomedian field with four, basolateral field with five chaetae, respectively (Fig. 8D ). Maxillary outer lobe with apical chaeta subequal to the basal chaeta, none barbed, sublobal plate with one chaeta-like appendage (Fig. 8E ). Labial palp with six proximal chaetae, formula of the guards: H (2), A (0), B (5), C (0), D (4), E (5) plus the lateral process (Fig. 8F ). Six prelabral chaetae present (Fig. 8C ); labral p, m, and a lines with 5, 5, 4 chaetae, respectively, p2 longer than the others, labral intrusions present, labral papillae absent, labrum apically without clear modifications (Fig. 8G ). Mandibles normal (not elongated), with 5+4 incisive apical teeth (Fig. 8H ). Maxilla capitulum elongate (Fig. 8I ).

Trunk (Fig. 9 ). Large abdomen: thorax continuous with the abdomen, without segmentations. Th. II with one a small chaeta and three blunt spines on m line; Th. III with one capitate a, two m and one p chaetae, p reduced in males and elongate in females; Abd. I with one a, one m and one p chaetae; Abd. II bothriotricha A, B, and C slightly misaligned, C clearly longer than A and B, with three a, five m, and seven p chaetae of different shapes near the bothriotricha, at least two of them clearly shorter in males; Abd. II with seven long capitate mac. Abd. III and IV with four main lines of chaetae above the bothriotrichum C: dI-1 with five, dII-1 with six, dIII-1 with three and dIV-1 with one capitate chaetae, respectively, female with some chaetae longer than on male (Fig. 9A ). Parafurcal area with four rows of chaetae, with three, three, two or three and four chaetae, respectively, neosminthuroid chaeta present. Three extra capitate chaetae between the bothriotrichum C and the parafurcal area (Fig. 9A ). Small abdomen: including Abd. V-VI in both sexes. Abd. V chaetae smooth, with bothriotrichum D with one small accessory chaeta, chaeta above bothriotrichum D elongate in females, absent in males (Fig. 9B, D ), Abd. VI chaetae apparently smooth. Female Abd. VI: dorsal anal valve with as1 - 4, ams1, ms1 - 4, mps1 - 3, and ps1 - 2 chaetae, as1, ams1, ms1, and ps1 unpaired; each ventral anal valve with ai1 - 6, ami1 (as an oval organ), mi1 - 5, mpi1 - 2, and pi1 - 3 chaetae, mi5 as the subanal appendage, long (surpassing the apex of the ventral anal valves), slightly curved at the apex, acuminate, and apically serrated on its internal face (Fig. 9B ). Female genital plate with 4+4 ventral chaetae (Fig. 9C ). Male Abd. VI: dorsal anal valve with as2 - 4, ms1 - 4, mps2, and ps1 - 2 chaetae, ms1 and ps1 unpaired; each ventral anal valve with ai1 - 4, ami1 (as an oval organ), mi1 - 5, mpi2, and pi1 - 3 chaetae (Fig. 9D ). Male genital plate with 14+14 chaetae (Fig. 9E ).

Abdominal appendages (Fig. 10A-C ). Ventral tube with 1+1 chaetae on the lateral flaps, sacs long and warty. Tenaculum ramus with three teeth each plus an apically rounded basal appendix, corpus with 2+2 chaetae. Manubrium with 7+7 dorsal chaetae (Fig. 10A ); dens ventrally (anteriorly) with six chaetae, following the formula from the apex to the basis: 3,2...1 (Fig. 10B ); dens dorsally without basal appendages, with 16 dorsal (posterior) chaetae (Fig. 10C ); Mucro short, apically split, external lamella serrated (with 12-18 serrations), internal with two distal weak crenulations, ending in a prominent apical notch (Fig. 10C ). Manubrium:dens:mucro ratio of the holotype = 1.05:2.4:1.

Legs (Figs 10D-F , 11 ). Leg I: epicoxa with one chaeta, subcoxa and coxa without chaetae; trochanter with two capitate spines plus two capitate chaetae (Fig. 10D ); femur with one oval organ, one acuminate large curved spine and ten regular chaetae; tibiotarsus with two oval organs and 46-47 chaetae, nine or ten of them in the apical whorl (Fig. 11A ); pretarsus with anterior chaeta longer than the posterior one, unguis with one internal, two lateral and one dorsal teeth, with tunica and weak pseudonychia, unguiculus with the tooth, apical filament thin and surpassing the tip of the unguis (Fig. 11B ). Leg II: epicoxa and subcoxa with one chaeta each, coxa with two chaetae, one of them curved, other capitate; trochanter with one thick capitate spine and four regular chaetae (Fig. 10E ); femur with one oval organ, two reduced and 10-11 regular chaetae; tibiotarsus with two oval organs and 47 chaetae, ten of them in the apical whorl (Fig. 11C ); pretarsus with anterior chaeta longer than the posterior one, unguis with one internal, two lateral and one dorsal teeth, with tunica and weak pseudonychia, unguiculus with the tooth, apical filament thin and surpassing the tip of the unguis (Fig. 11D ). Leg III: epicoxa and subcoxa with one chaeta each, coxa with four chaetae; trochanter with one thick blunt spine, one oval organ and five regular chaetae (Fig. 10F ); femur with one oval organ, two reduced and 12 regular chaetae; tibiotarsus with two oval organs and 50 chaetae, ten of them in the apical whorl (Fig. 11E ); pretarsus with anterior chaeta longer than the posterior one, unguis with one internal, two lateral and one dorsal teeth, with tunica and weak pseudonychia, unguiculus with the tooth, apical filament thin and not reaching the tip of the unguis (Fig. 11F ); tibiotarsi oval organs with reduced inner sensilla (Fig. 11A, C, E ). Ratio of ungues I-III in the holotype = 1:1.05:1.04.

Etymology.

The species was named after its color pattern; Szeptyckitheca cyanea from Latin means dark blue.

Habitat.

Specimens of S. cyanea sp. nov. were found in two localities ~ 30 km apart in the Rio Grande do Norte state, Brazil: in the central campus of the Federal University of Rio Grande do Norte, Natal municipality, and the National Forest of Nísia Floresta, Nísia Floresta municipality (Fig. 6 ). Both localities are inserted in the Atlantic Forest phytogeographic domain. The specimens were collected from the forest litter covering sandy soils in shady areas. The climate of the sampled municipalities is “As” following the Köppen-Geiger system, which means an equatorial climate with dry summer ( Kottek et al. 2006). The specimens were collected during the raining season of 2022.

Remarks.

Szeptyckitheca cyanea sp. nov. is the sole species of the genus with 18 spines on the head vertex. It is also the only Neotropical Szeptyckitheca with the frontal head A1 chaeta (see Table 1 ). Considering the Neotropical fauna, it is somewhat similar to S. andrzeji sp. nov. in the number of Ant. IV subsegments (11), Ant. I chaetae (6), and the presence of two capitate trochanteral spines on the leg I. However, they differ in the previously mentioned features, as well as the presence of secondarily reduced chaetae on the head frons of S. andrzeji sp. nov. (absent in S. cyanea sp. nov.), female subanal appendage morphology (short and spoon-like in S. andrzeji sp. nov., long and acuminate in S. cyanea sp. nov.) and ventral dens chaetotaxy formula (3 … 1 in S. andrzeji sp. nov., 3,2 … 1 in S. cyanea sp. nov.), among other characteristics. Further comparisons are presented in Tables 1 and 2 .

Figures

Figure 6. Known distribution of Szeptyckitheca andrzeji sp. nov. and Szeptyckitheca cyanea sp. nov. in Brazil A National Forest of Palmares, in Altos municipality, Piaui state B Federal University of Rio Grande do Norte, in Natal city, Rio Grande do Norte state C National Forest of Nisia Floresta, in Nisia Floresta municipality, Rio Grande do Norte state. In A and C, the white line polygons delimit the sampled areas boundaries.

Figure 7. Szeptyckitheca cyanea sp. nov. habitus in ethanol (lateral view).

Figure 8. Szeptyckitheca cyanea sp. nov. head A dorsal Ant. IV (white arrows point to chaetae present or absent) B dorsal Ant. I-III, detail shows the ventral apical organ and the small sensilla in cavities on Ant. III C anterior head chaetotaxy and eyes D labial and postlabial (ventral) chaetotaxy (left side), white arrow points to chaeta present or absent E maxillary outer lobe and sublobal plate (left side) F labial papillae and proximal chaetae alveoli (left side) G labrum H mandibles apexes I maxilla capitulum (left side).

Figure 9. Szeptyckitheca cyanea sp. nov. trunk chaetotaxy A male large abdomen, details show the neosminthuroid chaeta and its alveolus and longer chaetae of the female B female small abdomen C female genital plate D male small abdomen E male genital plate.

Figure 10. Szeptyckitheca cyanea sp. nov. trunk appendages A manubrium B ventral dens C dorsal dens and mucro D epicoxa, subcoxa, and coxa of leg I E epicoxa, subcoxa, and coxa of leg II F epicoxa, subcoxa, and coxa of leg III.

Figure 11. Szeptyckitheca cyanea sp. nov. legs A femur and tibiotarsus I (detail shows oval organs with internal small sensillum) B foot complex I C femur and tibiotarsus II (detail shows oval organs with internal small sensillum) D foot complex II E femur and tibiotarsus III (detail shows oval organs with internal small sensillum) F foot complex III.