Aphilodon bahianus, Calvanese & Brescovit, 2022

Calvanese, Victor C. & Brescovit, Antonio D., 2022, Six new species of Aphilodon centipedes (Geophilidae: Aphilodontinae) from Brazil, Zootaxa 5105 (4), pp. 539-558 : 555-557

Aphilodon bahianus new species

( Figs 11–12 )

Types. Holotype: ♀, from Parque Nacional do Descobrimento , Prado, Bahia, Brazil, 11–18/11/2018, V. Calvanese & A. Silva leg., deposited in IBSP 6460 . Paratypes: 2♀ ( IBSP 6462 ) and 2♂ ( IBSP 6461 ), same data as holotype .

Other material examined. BRAZIL. Bahia: Andaraí, Parque Nacional da Chapada da Diamantina, 29/ 11– 05/12/2018, V. Calvanese & A. Silva leg., 1♂ ( IBSP 6466 ); Mucugê, Parque Municipal de Mucugê , 29/ 11– 05/12/2018, V. Calvanese & A. Silva leg., 2♂ ( IBSP 6465 ); Prado, Parque Nacional do Descobrimento , 11/2018, V. Calvanese & A. Silva leg., 4♀ ( IBSP 6463 ); Una, Reserva Biológica de Una , 20–28/11/2018, V. Calvanese & A. Silva leg., 5♀, 5♂ ( IBSP 6464 ) .

Etymology. The epithet is an adjective and denotes the origin of the holotype, from the state of Bahia.

Diagnosis. Aphilodon bahianus n. sp. resembles A. foraminis n. sp. by lacking a distinct denticle of tarsungulum ( Figs 11A , 12C ), but differ from it by having the cephalic plate longer than wide, and without visible transverse suture ( Fig. 12B ) (cephalic plate wider than long and with transverse suture in A. foraminis n. sp.), tarsungulum distinctly curved and shorter than the trochanteroprefemur+femur ( Figs 11A , 12C ) (tarsungulum not curved and longer than the trochanteroprefemur+femur in A. foraminis n. sp.), and ultimate tarsus with a small terminal foraminis, and with a well developed terminal spinous ( Fig. 11C ) (ultimate tarsus with a large terminal foraminis, and with a small terminal spinous in A. foraminis n. sp.).

Description of holotype. Female (IBSP 6460).

General aspect: 65 leg-bearing segments; body 18 long, maximum width (middle part of trunk) 0.34. Color (preserved specimen in alcohol): head and forcipular segment ferruginous, leg-bearing segments and post-pedal segments yellowish ( Fig. 12A–G ).

Cephalic plate: longer than wide, 0.32 long, 0.29 wide (length/width ratio 1.1), without transverse suture, with short scattered setae ( Fig. 12B ).

Antennae: left antenna 0.93 long (2.9 times as long as cephalic plate); length/width ratio of articles II–XIII 0.4–0.7; length/width ratio of last article 1.9. Last article with ca. 6 claviform specialized setae on the external margin and ca. 4 on the internal margin. Morphology and chaetotaxy as in Fig. 12B–C .

Clypeus: 2+2 lateral setae; 2+2 post-antennal setae; 6+5 subclypeal setae.

Mandible: pectinate lamellae with ca. 20 denticles.

First maxillae: left telopodite length 0.029, width 0.018; distal article with one subapical sensillum; each medial projection of coxosternite with one apical and 2 subapical sensilla.

Second maxillae: 12 short setae distributed in a row along the anterior margin between the telopodites; coxosternite rectangular, not distinctly shorter in the middle part (length/width ratio 0.55), left telopodite length 0.054 (1.8 times as long as the telopodite of first maxillae), maximum width (basal margin) 0.023; each telopodite with one apical sensillum and two subapical setae on article 3.

Forcipular segment: metatergite trapezoidal, length 0.09 (0.3 times as long as cephalic plate), width 0.29 (length/ width ratio 0.3), with ca. 10 scattered setae; coxosternite length 0.30 and width 0.32 (length/width ratio 0.93); telopodite length 0.18, not reaching the anterior margin of the cephalic plate, with 2 denticles in the trochanteroprefemur+femur and 1 denticle in the tibia, all well developed; denticle distal of trochanteroprefemur with 1 apical seta, denticle corresponding to the vestigial femur bilobed and with 1 apical and 3 subapical setae, denticle of tibia with 2 apical and 2 subapical setae; tarsungulum 0.75 times as long as trochanteroprefemur+femur, without a visible denticle ( Figs 11A , 12B–C ).

Tergites from the first to penultimate leg-bearing segment: metatergites rectangular, with two rows of 6–6 setae and short scattered setae; in segment 35 metatergite length 0.16, width 0.33 (length/width ratio 0.5); in segment 35 pretergite 0.3 times as long as previous metatergite and with a row of 6 setae ( Fig. 12D ).

Walking legs: first leg 0.95 times as long as second leg, with procoxae extended to the midline of the body; leg of segment 32 length 0.4 ( Fig. 12A–G ).

Sternites from the first to penultimate leg-bearing segment: first metasternite semicircular, the other metasternites rectangular and elongated with scattered setae; in segment 35 metasternite length 0.2, width 0.12 (length/width ratio 1.6); presternite present throughout body, in segment 35 presternite 0.15 times as long as the previous metasternite and with one row of 7 setae ( Fig. 12C, E ).

Ultimate leg-bearing segment: metasternite wider than long, trapezoidal, length 0.14, maximum width 0.18 (length/width ratio 0.77); presternite evident only in the sides of the metasternite ( Fig. 12G ). Ultimate legs straight, length 0.9, about 2 times as long as penultimate leg; each coxopleuron with ca. 7 scattered coxal pores; tarsus 1.7 times as long as tibia ( Fig. 12G ).

Postpedal segments: gonopods with 3+3 distal setae.

Sexual dimorphism. Males with ultimate legs thickened ( Figs 11B , 12F ). Male gonopods biarticulated, article 1 with 3–6 setae, article 2 with 2–4 scattered setae.

Variation. N= 22, including 12♀ and 10♂ (from four localities): total body length: 16–21 mm. Leg-bearing segments: ♀ 63, 65; ♂ 63, 65. Coxal pores in each coxopleuron: 6–9.

Natural history. The specimens were sampled at about 5–10 cm deep or just below rotten logs, in large forests or in small forest fragments in open areas.

Distribution. Brazil, state of Bahia ( Fig. 13 ).

Figures

FIGURE 11. A–C, Aphilodon bahianus n. sp. Paratype male (IBSP 6461): A, forcipules, ventral; B, terminal part of body, ventral; C, terminal part of the left ultimate leg, lateral. Abbreviations: CP: coxal pores. TA: tarsungulum. TS: terminal spine. Scale bars: 0.05 (A–B), 0.005 (C) mm.

FIGURE 12. A–G, Aphilodon bahianus n. sp. Paratype, male (IBSP 6461): A, habitus, ventral; B, anterior part of body, dorsal; C, same, ventral; D, leg-bearing segments 15–16, dorsal; E, same, ventral; F, terminal part of body, ventral. Aphilodon bahianus n. sp. Holotype, female (IBSP 6460): G, terminal part of body, ventral. Scale bars: 1 (A), 0.2 (B–G) mm.

FIGURE 13. Biomes of Brazil and the known occurrence of the new species of Aphilodon: on the map of Brazil, dark green indicates the biome of Amazonia; orange Cerrado; yellow Caatinga; purple Pantanal; light green Atlantic Forest; beige Pampas. Red diamond: Aphilodon foraminis n. sp., Aphilodon aiuruocae n. sp. and Aphilodon acutus n. sp., yellow diamond: Aphilodon rectitibia n. sp., purple diamond: Aphilodon cangaceiro n. sp., and orange diamond: Aphilodon bahianus n. sp.