Avicularia gamba, Bertani, Rogério & Fukushima, Caroline Sayuri, 2009

Bertani, Rogério & Fukushima, Caroline Sayuri, 2009, Description of two new species of Avicularia Lamarck 1818 and redescription of Avicularia diversipes (C. L. Koch 1842) (Araneae, Theraphosidae, Aviculariinae) — three possibly threatened Brazilian species, Zootaxa 2223, pp. 25-47 : 32-36

publication ID	https://doi.org/ 10.5281/zenodo.190150
DOI	https://doi.org/10.5281/zenodo.6223899
persistent identifier	https://treatment.plazi.org/id/3427842A-FFB3-E73D-AABF-01FEECD7FE31
treatment provided by	Plazi
scientific name	Avicularia gamba
status	sp. nov.

Treatment

Avicularia gamba View in CoL sp. nov.

( Figs 9 View FIGURES 9 ─12; 16─17 Appendix III, Figs C1─C6)

Diagnosis: The male resembles those of A. diversipes and A. sooretama sp. nov. by lacking a tibial apophysis on leg I. It is distinguished from that of A. diversipes by the embolus being 3.5 times longer than the tegulum, with a curvature of less than 180° ( Figs 9 View FIGURES 9 ─11) and by the absence of orange stripes on the metatarsi. The male can be distinguished from that of A. sooretama sp. nov. by the absence of a spiniform process on the cymbium. The female resembles those of A. sooretama sp. nov. by retaining the characteristic juvenile color pattern on the abdomen (Fig. C2) and by the spermathecal shape (Fig. 12). It is distinguished by having spermathecae constricted at its base, slightly curved outwards and ending in rounded apex (Fig. 12). The male and female can be additionally distinguished from those of A. diversipes and A. sooretama sp. nov. by having leg I slightly longer than leg IV, rather than leg I slightly shorter than leg IV.

Etymology: The specific name is taken from the NGO " GAMBA – Grupo Ambientalista da Bahia", in recognition of their efforts in preserving Brazilian Atlantic rainforest remnants in the State of Bahia. The area in the RPPN Jequitibá where the new species was discovery is protected by GAMBA's initiative.

Material examined: Holotype male, Brazil, State of Bahia, Elísio Medrado, RPPN Jequitibá (12°52'3.20'' S, 39°28'9.09" W), R. Bertani, C.S. Fukushima and R.H. Nagahama, 7 October 2007, collected at night, found immature inside a retreat made with silk and leaves, matured in captivity on June 2009 ( MZSP 31115); paratype female, same data and collectors ( MZSP 31116).

Additional material examined: molts of live specimens maintained in laboratory.

Description: Holotype male. Carapace 7.3 long, 6.9 wide, chelicerae 2.1. Legs (femur, patella, tibia, metatarsus, tarsus, total): I: 9.3, 4.6, 7.8, 7.6, 4.0, 33.3. II: 8.5, 3.8, 7.1, 5.9, 3.8, 29.1. III: 7.0, 3.3, 5.9, 6.2, 3.3, 25.7. IV: 9.1, 3.9, 8.4, 8.4, 3.1, 32.9. Palp: 5.2, 3.1, 4.0, –, 1.6, 13.9. Midwidths: femora I–IV= 1.2, 1.3, 1.6, 1.5, palp= 1.0; patellae I–IV= 1.2, 1.2, 1.3, 1.3, palp= 1.0; tibiae I–IV= 1.0, 0.9, 1.0, 1.2, palp= 1.2; metatarsi I–IV= 0.8, 0.7, 0.8, 0.7; tarsi I–IV= 0.9, 0.8, 0.9, 0.9, palp= 1.2. Abdomen 8.2 long, 6.1 wide. Spinnerets: PMS, 0.6 long, 0.4 wide, 0.1 apart; PLS, 1.3 basal, 0.9 middle, 1.5 distal; midwidths 0.9, 0.8, 0.6, respectively.

Carapace: length to width 1.1; cephalic area moderately raised, thoracic striae visible. Fovea: shallow, straight, 1.0 wide. Carapace covered by short, slender setae and some long scattered setae mainly in cephalic region.

Eyes: tubercle high, length 1.2, width 1.9. Clypeus absent. Anterior eye row procurved, posterior slightly recurved. Sizes and inter-distances: AME 0.52, ALE 0.58, PME 0.15, PLE 0.51, AME–AME 0.33, AME– ALE 0.27, AME–PME 0.08, ALE–ALE 1.27, ALE–PME 0.58, PME–PME 1.17, PME–PLE 0.03, PLE–PLE 1.50, ALE–PLE 0.23, AME–PLE 0.35. Ratio of eye group width to length, 2.0.

Maxillae: length to width: 1.76; lyra absent. Cuspules: ca. 100 spread over ventral inner heel. Labium: length 1.0, width 1.4, with ca. 90 cuspules spaced by more than one diameter from each other on anterior third center. Labio-sternal groove shallow, flat, with two large sigilla.

Chelicerae: rastellum absent, basal segments with nine teeth in row and some small teeth on promargin.

Sternum length 3.9, width 3.3. Posterior angle sharp, but not separating coxae IV. Sigilla not visible.

Legs: legs formula: I=IV II III. Clavate trichobothria on distal 2/3 of tarsi I–IV. Leg coxae: with sparse soft setae; no stridulatory or modified setae. Tarsi I–II fully scopulate, III with sparse setae and IV divided by narrow row of setae. Metatarsi I–II scopulate for distal 4/5; III for distal 2/3; IV for distal 1/3; IV divided by row of setae. Scopula hairs longest at lateral areas of tarsi and metatarsi, giving a spatulate aspect to the articles. Spines absent on all legs and palps. Claws: ITC absent; STC without teeth. Tibial apophysis absent.

Urticating hairs: Type II on abdomen dorsum.

Palp. Embolus slender, long, with abrupt curve to retrolateral side on apical third ( Figs 9 View FIGURES 9 ─11). Cymbium: two subequal lobes, prolateral one triangular, without spiniform process on apex.

Color pattern: dark brown carapace bordered with light brown hairs; all legs and pedipalps dorsally dark brown. All appendages and carapace covered with light brown hairs with pinky sheen. All tarsi with central orange stripe. Sternum, labium, maxillae, coxae and legs ventrally brown. Leg rings on distal femora, tibiae and metatarsi pinkish. Orange hairs and broad red stripe over central area on dorsal brownish abdomen (Fig. C1).

Description: Paratype female. Carapace 7.5 long, 6.8 wide, chelicerae 3.9. Legs (femur, patella, tibia, metatarsus, tarsus, total): I: 6.2, 4.0, 5.1, 4.5, 2.8, 22.6. II: 5.6, 3.6, 4.4, 3.9, 2.8, 20.3. III: 4.8, 2.9, 3.6, 3.6, 2.5, 17.4. IV: 5.9, 3.4, 5.3, 4.8, 2.7, 22.1. Palp: 4.4, 2.7, 2.8, –, 3.2, 13.1. Midwidths: femora I–IV= 1.5, 1.4, 1.4, 1.4, palp= 1.2; patellae I–IV= 1.4, 1.5, 1.5, 1.5, palp= 1.2; tibiae I–IV= 1.4, 1.4, 1.3, 1.3, palp= 1.2; metatarsi I–IV= 1.2, 1.2, 1.1, 0.9; tarsi I–IV= 1.4, 1.3, 1.3, 1.3, palp= 1.4. Abdomen 9.3 long, 6.8 wide. Spinnerets: PMS, 1.1 long, 0.5 wide, 0.3 apart; PLS, 1.5 basal, 0.9 middle, 1.5 distal; midwidths 1.1, 0.8, 0.6, respectively.

Carapace: length to width, 1.1; cephalic area moderately raised, thoracic striae visible. Fovea: shallow, straight, 1.1 wide.

As in male, except:

Eyes: tubercle length 1.2, width 2.1. Clypeus absent. Sizes and inter-distances: AME 0.55; ALE 0.47; PME 0.25; PLE 0.38; AME–AME 0.32; AME–ALE 0.21; AME–PME 0.14; ALE–ALE 1.24; ALE–PME 0.43; PME–PME 1.11; PME–PLE 0.05; PLE–PLE 1.44; ALE–PLE 0.33; AME–PLE 0.39. Ratio of eye group width to length, 1.7.

Maxillae length to width, 1.7. Labium: length 1.1, width 1.6, with ca. 100 cuspules spaced by more than one diameter from each other on anterior third at center.

Chelicerae: basal segments with nine teeth on right side and 10 on left side, both with some small teeth on promargin.

Sternum length 4.1, width 3.3.

Legs: Tarsi I–III fully scopulate, IV divided by three-wide row of setae. Metatarsi III scopulate for distal 1/2, IV for distal 1/4; IV divided by row of three setae.

Urticating hairs: Type II on abdomen dorsum.

Genitalia: Two large spermathecae constricted at their base, slightly curved outwards and ending in rounded apex (Fig. 12).

Color pattern: carapace brown bordered with light brown hairs; all legs and pedipalps dorsally brown; longer hairs light brown with pinky and blue sheen. All tarsi with U-shaped orange mark. Sternum, labium, maxillae, coxae and legs ventrally brown, longer hairs distally whitish. Leg rings on distal femora, tibiae and metatarsi pinkish. Light brown abdomen covered with long red setae with pinky sheen dorsally. Dorsal abdominal pattern: Large central longitudinal black stripe with zigzag edges having three red spots. Posterior spot larger than two anterior; central longitudinal black stripe fused to with three well defined lateral back stripes on each side (Fig. C2).

Color pattern ontogeny: The color pattern of spiderlings and small juveniles is very similar among individuals of A. gamba sp. nov, A. diversipes and A. sooretama sp. nov.. Spiderlings have in the abdomen dorsum a longitudinal dark green stripe with a central long spot of the same color of the lateral abdomen (light yellowish green). Three ill-defined transverse stripes connecting to the longitudinal stripe are evident (Fig. C3). Slightly larger specimens have retained the metallic green pattern, but it is darker, mainly over the central carapace. Some lighter hairs can be seen over the lateral carapace, contrasting with the darker central area. In the abdomen dorsum, the central longitudinal stripe has zigzag edges, both longitudinal and transverse stripes become darker and the central spot inside it is yellow brown. The anterior part of the stripe bears two small spots (Fig. C4). In larger stadia, the metallic green/blue general pattern is still evident. The carapace is the same color as the legs and with light brown hairs on the lateral edges and coxae. The abdominal longitudinal black stripe with zigzag edge contrasts with the three red spots within it. The transverse stripes are now black and conspicuous (Fig. C5). In the adult female, the juvenile abdominal color pattern persists. The tarsi of all appendages have an orange U-shaped area; all legs and pedipalps have longer light brown hairs with pinkish and bluish sheen (Fig. C2). The adult male has a dark brown carapace, all appendages and carapace with light brown hairs with pinky sheen, all tarsi with a central orange stripe and light brown abdomen with orange hairs and a broad vivid red longitudinal stripe over the dorsocentral area (Fig. C1).

Distribution: Known only for type locality, Elísio Medrado, State of Bahia, Brazil ( Fig. 17 View FIGURE 17 ).

Natural History: All the exemplars found in RPPN Jequitibá in Elísio Medrado, State of Bahia, were collected at night on the entrance of their retreat on the vegetation (Fig. 16). The retreats were constructed on different types of plants and their distance from the soil ranged from a few centimeters, in the case of retreat on a grass ( Poaceae ) to about 2 meters from the ground (retreat constructed on trees). These specimens were collected in a restricted area on the RPPN Jequitibá, totally less than 100 m from the first exemplar to the last one collected in a straight line of a trail. In the same trail, we found a female of A. diversipes walking on a trunk.