Aphilodon spegazzinii Silvestri, 1898

Calvanese, Victor C., Brescovit, Antonio D. & Bonato, Lucio, 2019, Revision of the Neotropical species of Aphilodontinae (Geophilomorpha, Geophilidae), with eight new species and a first phylogenetic analysis of the subfamily, Zootaxa 4698 (1), pp. 1-72 : 21-23

Aphilodon spegazzinii Silvestri, 1898

( Figs 13A, C , 14–15 )

Aphilodon Spegazzinii [sic] Silvestri 1898: 40 (original description); Silvestri 1909a: 268 (in key); Silvestri 1909b: 54 (descrip- tion), 55, 56, fig. 9. Aphilodon Spegazzini [sic]: Brölemann 1902: 48. Aphilodon spegazzinii: Attems 1903: 283 ; Attems 1929: 315 (description; in key), fig. 282; Pereira 1998: 473; Foddai et al.

2000: 105; Pereira et al. 2007: 47 (in key); Bonato et al. 2011: 408; Koch & Edgecombe 2012: 41. Aphilodon spegazzini [sic]: Bücherl 1940: 313.

Type specimens. Syntypes: 4♀, 2♂ from “Las [sic] Talas, prope La Plata” ( Silvestri, 1898, 1909b), collected in 1898 (without name of collector), deposited in MCSG “Vase type XXVI”; specimens labeled “a–f”.

Type locality. Argentina: Los Talas, near La Plata .

Material examined. ARGENTINA. Misiones: Los Talas, near La Plata, 1898, 4♀, 2♂ [syntypes] (MCSG) .

Diagnosis. A species of Aphilodon with: around 61–65 leg-bearing segments; known body length in adults 22–45 mm; cephalic plate length/width ratio ca. 1.1; antenna ca. 3-4 times as long as t cephalic plate, with some articles longer than wide; pectinate lamella of mandible with straight denticles; coxosternite of second maxillae not distinctly shorter in middle part; telopodite of second maxillae with article 3 shorter than article 2, with 2 subapical setae and a short sensillum in between; forcipular pretergite exposed; forcipule with lateral margin posteriorly straight; tarsungulum 0.9 times as long as trochanteroprefemur+femur; forcipule with 3+1 denticles; distal denticle of trochanteroprefemur, denticle of femur and denticle of tibia relatively large and denticle of tarsungulum rela- tively small; distal denticle of trochanteroprefemur and denticle of femur separate; all pleurites conspicuous; each coxopleuron with 17–31 coxal pores in adults; ultimate presternite exposed and apparently divided in middle part; metasternite of ultimate leg-bearing segment length/width ratio ca. 1.4; ultimate legs ca. 1.6 times as long as penultimate legs, with tarsus 1 ca. 1.5 times as long as the tibia.

A. spegazzinii differs from all other species of Aphilodon by having antennae>3 times as long as cephalic plate ( Fig. 14A , 15B ) and metasternite of ultimate leg-bearing segment longer than wide ( Figs 14B , 15E ).

Recorded specimens: 6, including 4♀ and 2♂, from one locality.

Distribution. Argentina—Misiones: Los Talas, near La Plata ( Silvestri 1898, 1909b).

Description of a syntype. Female specimen “a”.

Entire body: length 35, maximum width 0.75. Cephalic plate: sub-quadrate, length 0.39 and width 0.37 (length/ width ratio 1.05). Antenna: length 1.32, 3.4 times as long as cephalic plate; AA II–IV length/width ratio 1.0–1.1; AA V–XIII length/width ratio 0.85–0.95; LAA ca. 2.0 times as long as the previous article.

Clypeus: 6+6 LS, 2+2 PS, 15+15 SCS. Mandible: PL with about 20 small denticles. First maxillae: TFM length 0.08 and width 0.03; DA with 1+1 SE and 3+3 SL; MPC with 1+1 SE. Second maxillae: 8 SE arranged in a row along the posterior margin of CSM, between TSM; left TSM length 0.07 (1.02 times as long as TFM) and maximum width (basal margin) 0.03; both T3 with 2 lateral SE and one little SL in subapical region.

Forcipular segment: FTE trapezoidal, length 0.19 (0.48 times as long as cephalic plate) and maximum width 0.51, with little scattered SE; FPT length 0.10 and width 0.30; FCX length 0.44 and width 0.50 (length/width ratio 0.88); left FRL length 0.36, two denticles on TFF and one in TI, all relatively large; FD1 with one apical and one subapical SE, FD2 with two apical and one subapical SE, FD3 with two apical and one subapical SE; TA with a small DTA, ca. 0.9 times as long as TFF.

Walking legs: 65 pairs; FL 0.82 times as long as the second leg, with procoxae not extended to the body midline; leg 35 with 0.4 long. Tergum from first to penultimate leg-bearing segment: TE rectangular, with slightly rounded lateral margins, not extending to the pleural region; TE 35 length 0.17 and width 0.35; with 2 rows of 8+8 SE and 2+2 lateral SE; PT quite evident along the body, ca. 1/3 as long and slightly narrower than the tergite; ca. 7 SE arranged in a row in central region of tergite. Sternum from first to penultimate leg-bearing segment: STF wider than long, ST uniformly rectangular, longer than wide; ST 35 length 0.25 and width 0.21; PST visible along the body as a continuous band.

Ultimate leg-bearing segment: MTL pentagonal, longer than wide, length 0.18 and width 0.12 (length/width ratio 1.40); UPS divided into two structures in sagittal plane. Ultimate legs: telopodite length 0.95, ca. 1.6 times as long as penultimate leg; each CXP with 28–31 COP, sparse and of varying diameters; tarsus 1 ca. 1.5 times as long as the tibia. Postpedal segments: GF with 1+1 distal SE.

Known variation. Male: GM biarticulated; GM1 wider than long, with about 8 SE in 2 rows; GM2 triangular, tapering to distal region, with 12–16 scattered SE.

Figures

FIGURE 13. A–D, Aphilodon diagnostic characters. Aphilodon spegazzinii Silvestri, 1898 (MSNG “Vase type XXVI”: specimen “b”): A, terminal spine in tarsus I of the left ultimate leg, lateral; C, female terminal part of the body, ventral. Aphilodon pereirai n. sp. (IBSP 3784): B, left telopodite of second maxillae, ventral; D, male terminal part of body, ventral. Abbreviation: TS: terminal spine. Scale bars: 0.01 (A–B), 0.5 (C–D) mm.

FIGURE 14. A–B, Aphilodon spegazzinii Silvestri, 1898 (MSNG “Vase type XXVI”: specimen “b”): A, antennal article III and IV, ventral; B, metasternite of the ultimate leg-bearing segment, ventral. Abbreviations: MTL: metasternite of the ultimate leg-bearing segment; UPS: ultimate presternite. Scale bars: 0.05 mm (A–B).

FIGURE 15. A–E, Aphilodon spegazzinii Silvestri, 1898 (MSNG “Vase type XXVI”: specimen “b”): A, habitus, ventral; B, anterior part of body, dorsal; C, same, ventral; D, terminal part of body, dorsal; E, same, ventral. Scale bars: 0.4 (A), 0.8 (B–C), 0.5 (D–E) mm.