Dinaphorura nerudai , Arbea, Javier I., 2016

Arbea, Javier I., 2016, Three new species and one new record of Tullbergiidae (Collembola: Onychiuroidea) from Tierra del Fuego, Zootaxa 4093 (1): -1

publication ID

http://doi.org/10.11646/zootaxa.4093.1.4

publication LSID

lsid:zoobank.org:pub:0479E963-AC6F-4E82-BDF2-C6F5146B8C2A

persistent identifier

http://treatment.plazi.org/id/03DF8784-B134-FFA9-FF63-924BC938298D

treatment provided by

Plazi

scientific name

Dinaphorura nerudai
status

sp. nov.

Dinaphorura nerudai  sp. nov.

Figs 27–35View FIGURES 27 – 31View FIGURES 32 – 35; Table 6

Type locality. Argentina, Tierra del Fuego, near Rio Grande (53 º 36 ’ S, 68 º 04’ W).

Type material. Holotype female, Tierra de Fuego, near Rio Grande, Argentina, Chiliotrichum  dense scrub, with Festuca gracillima  and Chiliotrichum diffusum  (after Collantes et al. 1999), S.M. Bonaventura and V. Mascitti leg., February 2001. Paratypes: All specimens from same locality as holotype, 44 females, 23 males and 46 juveniles. Holotype and 10 paratypes deposited in MACN, 10 paratypes in MNCN, and 93 paratypes in JIAP.

Description. Body shape elongate. Length 1.25 mm (female holotype), 1.1–1.4 mm (female paratypes), 0.9 – 1.0 mm (male paratypes). Colour white. Cuticular granulation of whole body relatively uniform but larger on posterior dorsum of Abd VI. Ungranulated cuticular ridges on dorsolateral anterior margins of Th III to Abd IV. Dorsal chaetae well differentiated into micro- and macrochaetae ( Fig. 27View FIGURES 27 – 31).

Antennae slightly shorter than head length ( Fig. 27View FIGURES 27 – 31), ratio of lengths 1: 1.1. Ant I, II, and III with 7, 11, and 18 ordinary chaetae respectively. AIIIO consists of three large sensory clubs with papillate protecting integumentary fold covering two small sensory rods between two outermost of these clubs; single sensillum located ventrally on Ant III. Ant IV with five thickened and curved sensilla (S 1, S 4, S 7, S 8 and S 9 after D’Haese (2003) = e, c, b, a and d respectively after Rusek (1971 )), one dorsoexternal microsensillum and one small subapical organite; apical vesicle absent ( Fig. 32View FIGURES 32 – 35).

PAO elongate, consisting on about 20 simple vesicles lying in two parallel rows. Coarse secondary cuticular granules form anterior margin of PAO ( Fig. 29View FIGURES 27 – 31). Labial palp with only papilla B (papillae A, C, D and E absent), 6 proximal chaetae and 3 hypostomal chaetae; basal parts of labium with 4 + 4 and 5 + 5 chaetae ( Fig. 33View FIGURES 32 – 35). Maxillary palp simple, without sublobal hair ( Fig. 33View FIGURES 32 – 35).

Pso semielliptical to circular, with crescent shaped opening with five distinct ridges (type III after Weiner & Najt 1991) ( Fig. 29View FIGURES 27 – 31). Pso formula 11 /011/ 11111 ( Fig. 27View FIGURES 27 – 31).

Dorsal chaetotaxy as in Fig. 27View FIGURES 27 – 31. Th pleurites I, II, III with 2, 3, 3 chaetae respectively. Chaetae s on Th and Abd slightly thickened, similar in form to ordinary chaetae. Th II and III with basally thickened chaeta s in position m 7 and microsensillum ms adjacent to it. Abd I –IV with chaeta s in position p 3. One chaeta s also present on Abd II – III as a 7, on Abd IV –V as p 5 and a pair lateral to genital opening. Full description of dorsal chaetotaxy is given in Table 6. Abd VI with two large, curved anal spines placed on low papillae. Ratio anal spine:claw III as 1–1.25: 1. Seven spiniform processes on Abd VI, located as follows: 1 + 1 dorso-medial (dm), 2 + 2 latero-dorsal (ld) and 1 unpaired medio-ventral (mv) ( Fig. 35View FIGURES 32 – 35).

Ventral chaetotaxy as in Fig. 28View FIGURES 27 – 31. Head with 3 + 3 postlabial chaetae. Th I –III sterna with 0,1+1, 1+ 1 chaetae respectively. Ventral tube with 4 + 4 distal and 2 + 2 basal chaetae. Abd V sternum with 1 + 1 slightly thickened chaeta s lateral to genital plate. Chaetotaxy of anal lobes as in Fig. 34View FIGURES 32 – 35.

Legs chaetotaxy from I to III, coxae, 3,4+7,4+ 7; trochanters 6,6–7,6– 7; femora, 11,11,11; tibiotarsi with 15 (7 + 8), 15 (7 + 8), 14 (7 + 7) chaetae respectively (A 1 to 7, B 1 to 7 and M present, B 7 absent on metatibiotarsus). Pretarsus with two chaetae each. Claw untoothed. Empodial appendage 0.15–0.25 the length of claw ( Figs 30–31View FIGURES 27 – 31).

Etymology. The new species is dedicated to the late Chilean poet Pablo Neruda for his 111 birthday (July 12, 1904).

Discussion. The new species belongs to the group of species with pso formula 11 /011/ 11111, Abd VI with 7 spiniform processes and elongate PAO, D. chazeaui Weiner & Najt, 1991  , D. harrisoni Bagnall, 1948  , D. laterospina Salmon, 1941  , D. matileorum Najt, 1988  , D. pefauri Rubio & Najt, 1979  and D. spinosissima (Wahlgren, 1906)  (Table 8). They differ in the number of vesicles on PAO (more than 26 vesicles in D. laterospina  and D. pefauri  ), the apical vesicle on Ant IV (present and conspicuous in D. laterospina  , D. pefauri  , D. harrisoni  and D. spinosissima  ) and the dorsal chaetotaxy (Table 8).

Dinaphorura najtae  sp. nov.

Figs 36–43View FIGURES 36 – 37View FIGURES 38 – 43; Table 7

Type locality. Argentina, Tierra del Fuego, near Rio Grande (53 º 36 ’ S, 68 º 04’ W).

Type material. Holotype female, Tierra de Fuego, near Rio Grande, Argentina, Chiliotrichum  dense scrub, with Festuca gracillima  and Chiliotrichum diffusum  (after Collantes et al. 1999), S.M. Bonaventura and V. Mascitti leg., February 2001. Paratypes: All specimens from same locality as holotype, 41 females, 7 males and 6 juveniles. Holotype and 10 paratypes deposited in MACN, 10 paratypes in MNCN, and 34 paratypes in JIAP.

Description. Body shape elongate. Length 0.7 mm (female holotype), 0.6–0.9 mm (female paratypes), 0.6–0.7 mm (male paratypes). Colour white. Cuticular granulation of whole body relatively uniform but larger on posterior dorsum of Abd VI. Ungranulated cuticular ridges on dorsolateral anterior margins of Th III to Abd IV. Dorsal chaetae well differentiated into micro- and macrochaetae ( Fig. 36View FIGURES 36 – 37).

TABLE 8. Main diagnοstic characters οf Dinaphorura nerudai  sp. nov., Dinaphorura najtae  sp. nov. and related species in the genus Dinaphorura  with 11 ⁄011⁄ 11111 dοrsal psο. "?"‾‾denοtes∶ nο data available. (1) SP-Spinifοrm prοcesses οn Abd vI∶ N‾‾Τοtal number (anal spines nοt included), dm‾‾dοrsοmedial, ld‾‾laterοdοrsal and mv‾‾mediοventral prοcesses, a∶p‾‾Ratiο anteriοr∶pοsteriοr laterοdοrsal prοcesses; (2) PAΟ-Fοrm, E‾‾elοngate, Τ‾‾triangular, and Number οf vesicles; (3) Av-Apical vesicle οn Ant Iv, B‾‾bilοbed, S‾‾simple, Τ‾‾trilοbed; (4) AS ∶C-Ratiο anal spine∶claw length; (5) Dοrsal chaetοtaxy∶ m, ca, p chaetae series.

(*) Abd vI with 2 large curved anal hοrns οn papillae and nine shοrt fat spines after οriginal descriptiοn, but οnly 7 spinifοrm prοcesses are shοwn in the οriginal drawing (Fig. 134).

Antennae slightly shorter than head length ( Fig. 36View FIGURES 36 – 37), ratio of lengths 1: 1.15. Ant I, II, and III with 7, 11, and 18 ordinary chaetae respectively. AIIIO consists of three large sensory clubs with papillate protecting integumentary fold covering two small sensory rods between the two outermost of these clubs; single sensillum located ventrally on Ant III. Ant IV with five thickened and curved sensilla (S 1, S 4, S 7, s 8 and S 9 after D’Haese (2003) = e, c, b, a and d respectively after Rusek (1971 )), one dorsoexternal microsensillum and one small subapical organite; apical vesicle absent ( Fig. 42View FIGURES 38 – 43).

PAO triangular, consisting on 18–20 irregularly shaped vesicles in two rows. Coarse secondary cuticular granules form anterior margin of PAO ( Fig. 43View FIGURES 38 – 43). Labial palp with only papilla B (papillae A, C, D and E absent), 6 proximal chaetae and 3 hypostomal chaetae; basal parts of labium with 4 + 4 and 5 + 5 chaetae ( Fig. 41View FIGURES 38 – 43). Maxillary palp simple, without sublobal hair ( Fig. 41View FIGURES 38 – 43).

Pso semielliptical to circular, with crescent shaped opening with five distinct ridges (type III after Weiner & Najt 1991) ( Fig. 43View FIGURES 38 – 43). Pso formula 11 /011/ 11111 ( Fig. 36View FIGURES 36 – 37).

Dorsal chaetotaxy as in Fig. 36View FIGURES 36 – 37. Th pleurites I, II, III with 2, 3, 3 chaetae respectively. Chaetae s on Th and Abd slightly thickened, similar in form to ordinary chaetae. Th II and III with basally thickened chaeta s in position m 7 and microsensillum ms adjacent to it. Abd I –IV with chaeta s in position p 3. One chaeta s also present on Abd II – III as a 7, on Abd IV –V as p 5 and a pair lateral to genital opening. Full description of dorsal chaetotaxy is given in Table 7. Abd VI with two large, curved anal spines placed on low papillae. Ratio anal spine:claw III as 1–1.17: 1. Seven spiniform processes on Abd VI, located as follows: 1 + 1 dorso-medial (dm), 2 + 2 latero-dorsal (ld) and 1 unpaired medio-ventral (mv) ( Fig. 39View FIGURES 38 – 43).

Ventral chaetotaxy as in Fig. 37View FIGURES 36 – 37. Head with 3 + 3 postlabial chaetae. Th I –III sterna with 0,1+1, 1+ 1 chaetae respectively. Ventral tube with 4 + 4 distal and 2 + 2 basal chaetae. Abd V sternum with 1 + 1 slightly thickened chaeta s lateral to genital plate. Chaetotaxy of anal lobes as in Fig. 38View FIGURES 38 – 43.

Legs chaetotaxy from I to III, coxae, 3,4+7,4+ 7; trochanters 6,6,6; femora, 11,11,11; tibiotarsi with 15 (7 + 8), 15 (7 + 8), 14 (7 + 7) chaetae respectively (A 1 to 7, B 1 to 7 and M present, B 7 absent on metatibiotarsus). Pretarsus with two chaetae each. Claw untoothed. Empodial appendage 0.23–0.28 the length of claw ( Fig. 40View FIGURES 38 – 43).

Etymology. The new species is dedicated to the late Judith Najt, a prominent Argentinean researcher of collembolan fauna, who passed away in 2014.

Discussion. The new species is most similar to D. americana Rapoport, 1962  and D. jarai Najt & Rubio, 1978  , they share the pso formula 11 /011/ 11111 and triangular PAO (Table 8), but they differ in the number of vesicles on PAO (12–15 in D. americana  , 10-11 in D. jarai  vs 18–20 in the new species), the number of spiniform processes on Abd VI (5 in D. jarai  vs 7 in D. americana  and D. najtae  sp. nov.), the apical vesicle on Ant IV (present in D. jarai  and D. americana  vs absent in the new species) and the dorsal chaetotaxy (Table 8).

TABLE 6. Dinaphorura nerudai sp. nov. Dorsal chaetotaxy of adult specimens. Abbreviations: m –– mesochaeta; M –macrochaeta; s (S) –– chaeta (macrochaeta) s; ms –– microsensillum; AS –– anal spines; “ – “ –– denotes absence of chaeta.

            S+ms
Abd II –III            

TABLE 7. Dinaphorura najtae sp. nov. Dorsal chaetotaxy of adult specimens. Abbreviations: m –– mesochaeta; M –macrochaeta; s (S) –– chaeta (macrochaeta) s; ms –– microsensillum; AS –– anal spines; “ – “ –– denotes absence of chaeta.

              S+ms
Abd II-III