Linothele fallax
Creators: name: Drolshagen, Bastian
name: Bäckstam, Christian M.
Publisher: name: Zenodo
Year: 2021
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Araneae
Dipluridae
Linothele
Linothele fallax

description: Linothele fallax (Mello-Leitão, 1926)
(Figs 2; 7; 18 A-C; 19 H-J)
Diplura fallax Mello-Leitão, 1926: 312.
Uruchus fallax — Bücherl et al. 1971: 122, figs 9-10. Linothele fallax — Raven 1985: 74, 75. — Silva-Moreira et al. 2010: 31. — Kury et al. 2018: 557.
TYPE MATERIAL. — Holotype. Brazil • ♀; Alto Jurua; Alvaro Leitão leg; MNRJ 44 (MLPC 679), probably lost.
OTHER MATERIAL EXAMINED. — Bolivia • 1 ♀ *; Beni, near Rurrenabaque; 2005; A. Stirm leg.; NHRS-KASI000000039 • 1 ♂ F1; same data as for preceding; NHRS-KASI 000000038 • 1 ♀ F1; same data as for preceding; NHRS-KASI000000040 • 1 undet. F2; same data as for preceding; NHRS-KASI000000041 • 1 undet. F2; same data as for preceding; NHRS-JUST000000529 • 2 ♂ F2 and 1 ♀ F2; same data as for preceding; SMNK.
TYPE LOCALITY. — Alto Juruá, Brazil.
DISTRIBUTION. — Juruá, Brazil to Rurrenabaque, Bolivia.
DIAGNOSIS. — The male of Linothele fallax can be distinguished from those of other species of Linothele by the almost straight megaspine, the position of the MP [(IML*100)/MAD = 442] and its v-shaped apex (Fig. 7C, D), as well as the embolus [(PL*100)/BD = 322] bearing no keel (Fig. 7A, B). It can further be distinguished from the male of L. jelskii by the leg formula of 4123 rather than 1423. Females of Linothele fallax differ from those of most other species of Linothele by their undivided scopula. They can be distinguished from those of L. gaujoni by their narrow clypeus (Fig. 7H) and their spermathecae stalks bearing a single retrolateral lobe (Fig. 7G). Females furthermore differ from the female of L. uniformis n. sp. by their higher number of maxillary cuspules (Fig. 7F), as well as their spermathecae bearing a single retrolateral lobe (Fig. 7G).
DESCRIPTION
Male
CL = 12.0. CT = 12-13. MC = 48. Colouration in alcohol: Prosoma, chelicerae, legs and pedipalps brown; opisthosoma dorsally with pattern consisting of complete chevrons; maculae absent. Colouration alive (Fig. 19I): as for alcohol, but patterns slightly more distinct. Carapace covered with orange setae. Opisthosoma with dorsal chevron pattern (Fig. 18A). Clypeus: narrow. Leg formula: 4123. Preening-combs absent. Leg tarsi pseudo-segmented. Spinnerets: apical segments of the PLS rigid. Palpal organ: [(PL*100)/BD = 322], see Figure 7A, B. Megaspine and MP: [(IML*100)/MAD = 483], see Figure 7C, D.
Female
Colouration as for male, but carapace in alive specimens either orange, or green and pattern on opisthosoma more distinct (especially in younger specimens; Figs 18B, C; 19H, J). Clypeus: narrow, see Figure 7H. Sternum, labium and maxillae: see Figure 7F. Leg formula: 4123. Scopula undivided. Preening-combs absent. Leg tarsi pseudo-segmented. Spinnerets: apical segment of the PLS rigid, see Figure 7E. Spermathecae: consisting of two stalks, bearing an isolated retrolateral lobe at 1:3A, see Figure 7G.
Variability
CL = 14.7-16.5. CT = 10-12. MC = 30-50.
REMARKS
According to the first description (Mello-Leitão 1926), the type locality is “Alto Juruá”. Bücherl et al. (1971) and Silva- Moreira et al. (2010) referred to the type locality as Juruá, Amazonas, ignoring the “alto” part, which might actually refer to the “upper” Jurua river at Peru and Acre, Brazil; thus, the type locality is somewhat ambiguous. The holotype could not be located by Silva-Moreira et al. (2010).
Material from Bolivia was found to match the descriptions by Mello-Leitão (1926) and Bücherl et al. (1971), as well as the illustration of the spermatheca provided by the latter.
NATURAL HISTORY
Linothele fallax can be found in natural crevices near ground level, but also in burrows in the ground. The spiders seem not to burrow, but occupy existing crevices. They usually produce less extensive funnel-webs, which end in a short funnel at the entrance of their burrow. Females produce an egg-sac with up to 120 eggs as a fixed hammock, usually attached to the entrance funnel or shortly behind in the tubular retreat. Unfortunately, we lack information on the time of the year the spiders mature and produce offspring in the wild. Under artificial conditions females started to build their egg-sacs after the humidity has been raised, indicating that mating and oviposition take place at the start of the wet season.
description: Published as part of Drolshagen, Bastian & Bäckstam, Christian M., 2021, A taxonomic review of the mygalomorph spider genus Linothele Karsch, 1879 (Araneae, Dipluridae), pp. 163-196 in Zoosystema 43 (10) on pages 174-175, DOI: 10.5252/zoosystema2021v43a10, http://zenodo.org/record/4720674