Megaphobema teceae, Pérez-Miles, Fernando, Miglio, Laura T. & Bonaldo, Alexandre B., 2006

Pérez-Miles, Fernando, Miglio, Laura T. & Bonaldo, Alexandre B., 2006, Megaphobema teceae n. sp. (Araneae, Theraphosidae), a new theraphosine spider from Brazilian Amazonia, Zootaxa 1115, pp. 61-68 : 63-65

Megaphobema teceae sp. nov.

Figs. 1–8 . Tables 1–2

Types. Male holotype from Igarapé Mutum Valley, Platô do Rio Juruti, Juruti, Pará, Brazil (2º3636” S, 56º127.1”W), 411 Nov 2002, T. C. Ávila­Pires col. (MPEG 1113); seven males and one female paratypes, same data (MPEG 1134, 1135; FCE­MY 690; IBSP 11200); female paratype, same locality (2º36’45.2”S, 56º11’27.5”W), 09.IX.2002, A. B. Bonaldo col. (MPEG 1092); two males and two females paratypes, same locality (2º36’11.2”S, 56º12’36.3”W), 0311. VIII.2004, D. R. Santos­Souza, D. F. Candiani (MPE G 2024, 2025, 2026, 2027).

Etymology. The specific epithet is a patronym in honor of the herpetologist Teresa Cristina Ávila­Pires , nicknamed TC (spelled Tecê, in Portuguese), who collected most of the types in pitfall traps while surveying for the herpetological inventory.

Diagnosis. Differs from other species of Megaphobema in the presence of a postocular tubercle ( Figs. 1–3 ) in males and females.

Description. Male: (Holotype). Total length, excluding chelicerae and spinnerets 63.4; carapace 32.0 long, 30.3 wide. Anterior eye row procurved, posterior slightly recurved. Eyes sizes and interspaces: AME 0.60, ALE 0.65, PME 0.85, PLE 0.90, AME­ AME 0.70, AME­ALE 0.70, PME­PME 2.10, ALE­PLE 0.40, clypeus 1.2. Subconical tubercle between ocular tubercle and fovea ( Fig. 1 ). Fovea transverse, slightly procurved, 4.7 wide. Labium 4.0 long, 4.2 wide with 75 cuspules, maxillae with 142 cuspules on each. Sternum 13.2 long, 12.1 wide; sigilla submarginal. Chelicerae with 8 teeth (5 proximal, smaller). Tarsi I­IV all densely scopulate and entire. Metatarsi I and II fully scopulate, scopula on III in distal half, and on IV in distal 1/3. Retrolateral face of femur IV with conspicuous scopula. Tibia I with prolateroventral, distal double apophysis ( Fig 4, 5 ). Metatarsus I is flexed at outer side of tibial apophysis. Palpal organ with subtegulum extended, wide and stylus wide and flattened (convex­concave); also with prolateral superior and inferior keels, three prolateral accessory keels and apical keel ( Figs. 6, 7 ). Femur III incrassate ( Table 3 ). Spination: Femora I–V and palp I 1 R; palp 1P. Patellae I–III and palp 0, IV 1 R. Tibiae I 1 V, II 2 V, III 4 P, 1R, 2V, IV 6 P, 1R, 6V, palp 7R, 3V. Metatarsi I–II and palp 0, III 5 P, 11V, IV 6 P, 22V. Tarsi I–IV and palp 0. Cephalothorax dark brown, abdomen and legs dark brown with longer reddish hairs. Types I and III urticating hairs present.

Female (Paratype, MPEG1092): Total length, excluding chelicerae and spinnerets 52.3. Cephalothorax 21.8 long, 21.1 wide. Anterior eye row procurved, posterior slightly recurved. Eyes sizes and interspaces: AME 0.60, ALE 0.80, PME 0.70, PLE 0.80, AME­ AME 0.60, AME ALE 0.80, PME­PME 1.95, PME­PLE 0.08, ALE­PLE 0.60, clypeus 0.50. Subconical tubercle between ocular tubercle and fovea ( Fig. 1 ). Fovea slightly procurved, 2.3 wide. Labium 1.8 long, 1.7 wide, with 59 cuspules, maxillae with 157 cuspules each one. Sternum 9.8 long, sigilla submarginal. Chelicerae with 11 teeth (7 of them proximal smaller). Tarsi densely scopulate: entire on I–III, divided by narrow strip of conical setae on IV. Scopula on metatarsus I entire, II for distal ¾, III for distal 1/3 and absent on IV. Retrolateral face of femur IV with conspicuous scopula. Femur III incrassate ( Table 4). Spination: Femora I–IV and palp 0. Patellae I–II and palp 0; III 1 p, 1r; IV 1 p, 3r. Tibiae I 1 p, 1r; II 1 p, 1r, 4v; III 2 p, 2r, 8v; IV 5 p, 3r, 7v; palp 9p, 1r, 6v. Metatarsi I 0; II 1 p, 1r, 3v; III 7 p, 2d, 1r, 9v; IV 14 p, 2r, 10v. Tarsi I–IV and Palp 0. Spermathecae with only one receptacle (completely fused) transversely striated. Color as in male. Types I and III urticating hairs present.

Distribution. Megaphobema teceae is only known from the type locality, Juruti River Plateau, Juruti, Pará, Brazil; no further data are known.

Variation. Males (n=10, including holotype): variation in eye sizes and interdistances (mean standard deviation). AME 0.59 0.09, ALE 0.63 0.06, PME 0.56 0.07, PLE 0.69 0.06, AME­AME 0.58 0.07, AME­ALE 0.60 0.28, PME­PME 1.68 0.28, PME­ PLE 0.12 0.03, ALE­PLE 0.43 0.11. Clypeus: 1.80 0.55. Fovea straight to slightly procurved, 5.85 1.16 width. Labium 4.32 0.38 long; 4.32 0.61 wide. Sternum 12.85 1.21 long, 12.01 1.18 wide. Number of cuspules on labium 71.5 16.8; on maxillae 169.0 18.0. Variation in spination is as follows (minimum /maximum): femora I­IV 0; palp 0/1 d. Patellae I 0/1p, 1r; II 0/1p, 0/1r; III 1 /3p, 0/1r; IV 0/2p, 0/2r; palp 1p, 0/1r. Tibiae I 0/2p, 0/4 r, 5v; II 3 /4p, 0/3r, 3/ 8v; III 6/10 p, 2/4r, 5/11v; IV 6 /9p, 0/1d, 6/7r, 7/10v; palp 3/9p, 0/7r, 3/ 7v. Metatarsi I 3 v; II 1 p, 0/1d, 0/3r, 3/ 4v; III 4 /9p, 1/4d, 1/3r, 8/12 v; IV 9/17 p, 0/1d, 12/16r, 14/20v; palp 0. Tarsi I–IV and palp, 0. Cheliceral teeth 9–12, distal large teeth 3; proximal small teeth 6–9. Variation in length of carapace, leg and palpal segments of males are given in Table 3 . Variation in size of the dorsal tubercle on the male carapace may be striking (see Figs. 1 and 3 ).

Females (n=4) AME 0.59 0.14, ALE 0.58 0.05, PME 0.61 0.14, PLE 0.70 0.14, AME­AME 0.45 0.06, AME­ALE 0.51 0.13, PME­PME 0.14 0.05, PME­PLE 0.14 0.05, ALE­PLE 0.33 0.05. Clypeus 1.98 0.68. Fovea straight to slightly procurved 5.76 2.41 wide. Labium 3.08 0.91 long, 3.86 1.54 wide. Sternum 12.75 2.10 long, 11.64 2.60 wide. Cuspules on labium 64.25 13.05; on maxillae 163 19.7. Spination: femora I–IV 0; palp 0/1p, 0/1d. Patellae I 0, II 0/1p; III 1 /2 p, 0/2r; IV 1 /2p, 0/2r; palp 0/ 1p. Tibiae I 1 /3p, 3/ 5v; II 2 /3p, 0/2d, 3/ 5v; III 4 /7p, 1/3r, 4/ 7v; IV 2 /8p, 1/5r, 7/10v; palp 3/5p, 1/3r, 8/11v. Metatarsi I 3 / 5v; II 1 p, 0/1d, 4v; III 5/11 p, 1/4r, 6/15v; IV 5 /7p, 3/5r, 20/23v; palp 0. Tarsi I–IV and palp 0. Cheliceral teeth 10–11, distal large teeth 3. Variation of length of carapace, leg and palpal segments of females are given in Table 4.

Natural History. The Juruti River Plateau was subjected to intense wood extraction in the past, especially of Pau­Rosa tree ( Aniba sp.). As a result, the original terra firme (dry land) primary forest (Dense Ombrophylous Submontane Forest) was mostly replaced by secondary forest. Due to the difficult access, some portions of terra firme forest, in various degrees of degradation, survived in the low valleys formed by the small creeks (igarapés), which arise in the plateau. All specimens came from disturbed primary forest in the vicinity of Igarapé Mutum. Seven males, including the holotype, were collected in pitfall traps for herpetological inventory, in September, 2002. At that time, a single female was also collected manually, in the afternoon, under log with scarce silk. On later expedition to the area (in August 2004), two females and two males were collected manually during one hour of manual searching at night.

Figures

FIGURES 1 – 5. Megaphobema teceae n. sp., male holotype: 1 lateral view; 2 ­ dorsal view. Male paratype (MPEG 1035), cephalothorax: 3 ­ lateral view. Male holotype, tibial apophysis: 4 prolateral view; 5 ventral view. Scale bars: Figs. 1 3 = 10 mm; Figs. 4, 5 = 3 mm.

FIGURES 6 – 8. Megaphobema teceae n. sp., male holotype, left embolus: 6 retrolateral view; 7 ­ prolateral view. Female paratype (MPEG 2025), spermatheca: 8 ­ ventral view. Scale bars: Figs 6, 7, 8 = 2 mm.

Tables

TABLE 3. Megaphobema teceae sp. n. Variation in 10 males including the holotype; dimensions of carapace and leg segments. Mean standard deviation.

	I	II	III	IV	Palp
Fe	16.7	15.9	14.7.	18.4	10.2
Pa	8.5	8.7	7.8	8.2	6.1
Ti	13.5	8.9	11.0	15.7	8.5
Mt	12.1	11.9	13.2	11.3	­
Ta	9.1	8.8	7.9	9.3	9.2