Aphilodon cangaceiro, 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 : 552-555

Aphilodon cangaceiro new species

( Figs 9–10 )

Types. Holotype: ♀, from Parque Nacional da Serra das Confusões, Caracol, Piauí, Brazil, 03–17/01/2019, V. Calvanese & A. Silva leg., deposited in IBSP 6455 . Paratypes: 2♀ ( IBSP 6457 ) and 2♂ ( IBSP 6456 ), same data as holotype .

Other material examined. 3♀ ( IBSP 6459 ) , 10♂ ( IBSP 6458 ), same data as types .

Etymology. The epithet is an adjective, that means inhabitant of Caatinga, and is a reference to the locality of the type.

Diagnosis. Aphilodon cangaceiro n. sp. resembles A. aiuruocae n. sp. by having the coxal pores all grouped along the lateral membranes between the coxopleuron and metasternite ( Figs 9E , 10E ), but differ from it by having a body between 20–30 mm long (7–10 mm long in A. aiuruocae n. sp.), number of leg-bearing segments between 87–93 ( Fig. 10A ) (41–43 in A. aiuruocae n. sp.), and by the metatergite, pretergite, metasternite and presternite of the walking leg-bearing segments with shape elongated ( Fig. 9B, D ) (not elongated in A. aiuruocae n. sp.).

Description of holotype. Female (IBSP 6455).

General aspect: 91 leg-bearing segments; body 24 long, maximum width (middle part of trunk) 0.22. Color (preserved specimen in alcohol): head and forcipular segment pale ferruginous, leg-bearing segments and postpedal segments whitish ( Fig. 10A–E ).

Cephalic plate: longer than wide, 0.23 long, 0.17 wide (length/width ratio 1.35), without transverse suture, with short scattered setae ( Fig. 10B ).

Antennae: left antenna 0.58 long (2.5 times as long as cephalic plate); length/width ratio of articles II–XIII 0.4–0.8; length/width ratio of last article 2.4. Last article with ca. 8 claviform specialized setae on the external margin and ca. 6 on the internal margin. Morphology and chaetotaxy as in Fig. 10B–C .

Clypeus: 3+3 lateral setae; 2+2 post-antennal setae; 5+4 subclypeal setae.

Mandible: pectinate lamellae with ca. 15 denticles.

First maxillae: left telopodite length 0.028, width 0.016; distal article with 2 subapical sensilla; each medial projection of coxosternite with one apical and 2 subapical sensilla.

Second maxillae: 9 little setae distributed in a row along the anterior margin between the telopodites; coxosternite rectangular, not distinctly shorter in the middle part, length/width ratio 0.6, left telopodite length 0.06 (2.1 times as long as the telopodite of first maxillae) and maximum width (basal margin) 0.027; each telopodite with one apical sensillum and two subapical setae on article 3.

Forcipular segment: metatergite trapezoidal, length 0.075 (0.32 times as long as cephalic plate), width 0.17 (length/ width ratio 0.44), with 12 scattered setae; coxosternite length 0.21, width 0.22 (length/width ratio 0.95); 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 relatively large; denticle distal of trochanteroprefemur with 1 apical seta, denticle corresponding to the vestigial femur bilobed with 1 apical and 2 subapical setae, denticle of tibia bilobed with 2 apical and 2 subapical setae; tarsungulum 0.86 times as long as the trochanteroprefemur+femur, with a denticle ( Figs 9A , 10B–C ).

Tergites from the first to penultimate leg-bearing segment: metatergites rectangular or subquadratic, with two rows of 5–5 setae; in segment 17 metatergite length 0.13, width 0.16 (length/width ratio 0.8); in segment 17 pretergite 0.74 times as long as previous metatergite, with ca. 10 scattered setae ( Fig. 9B ).

Walking legs: first leg 0.9 times as long as second leg, with procoxae extended to the midline of the body; leg of segment 17 length 0.25 ( Figs 9B–E , 10A–C ).

Sternites from the first to penultimate leg-bearing segment: first metasternite relatively elongated, semicircular, the other metasternites rectangular and elongated, with scattered setae; in segment 17 metasternite length 0.18, width 0.086 (length/width ratio 2.1); presternite elongated throughout the body, in segment 17 presternite length 0.11, width 0.19 (length/width ratio 0.55), 0.6 times as long as previous metasternite, with two rows of ca. 5+5 setae ( Fig. 9D ).

Ultimate leg-bearing segment: metasternite wider than long, trapezoidal, length 0.06, maximum width 0.13 (length/width ratio 0.4); presternite elongated, 0.44 times as long as previous metasternite ( Fig. 9E ). Ultimate legs straight, length 0.47 (2.2 as long as penultimate leg); each coxopleuron with 4 coxal pores opening below to the metasternite; tarsus 1.6 times as long as tibia, with a well developed terminal spine ( Fig. 9E–F ).

Postpedal segments: gonopods remarkably membranous, with 2+2 distal setae.

Sexual dimorphism. Males with ultimate legs thickened ( Fig. 10D–E ), gonopods biarticulated, article 1 with 2–4 setae, article 2 with 2–5 scattered setae.

Variation. N= 18, including 6♀ and 12♂ (from a single locality): total body length: 20–30 mm. Leg-bearing segments: ♀ 89, 93; ♂ 87, 89, 91. Coxal pores in each coxopleuron: 4–6.

Natural history. All collected specimens were found totally rolled up and forming a kind of ball, at about 5–10 cm deep, close to the roots, in forest between large rocks, in the Parque Nacional da Serra das Confusões, in areas of Caatinga biome.

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

Figures

FIGURE 9. A–F, Aphilodon cangaceiro n. sp. Female (IBSP 6459): A, anterior part of body, ventral; B, leg-bearing segments 11–12, dorsal; C, leg-bearing segments 33–34, lateral; D, leg-bearing segments 44–45, ventral; E, terminal part of body, ventral; F, terminal part of the left ultimate leg, ventral. Abbreviations: MS: metasternite. MT: metatergite. PS: presternite. PT: pretergite. TS: terminal spine. Scale bars: 0.1 (A–E), 0.005 (F) mm.

FIGURE 10.A–E, Aphilodon cangaceiro n. sp. Male (IBSP 6458): A, habitus, ventral; B, anterior part of body, dorsal; C, same, ventral; D, terminal part of body, dorsal; E, same, ventral. Scale bars: 1 (A), 0.2 (B–E) 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.