Caerostris bankana Strand 1915
Creators: name: Gregorič, Matjaž
name: Yu, Kuang-Ping
name: Velez, Winny Rojas
name: Garb, Jessica E.
Publisher: name: Zenodo
Year: 2025
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Araneae
Araneidae
Caerostris
Caerostris bankana

description: Caerostris bankana Strand, 1915
Fig. 3; Appendix 1
Caerostris bankana Strand, 1915: 225 (♀).
Diagnosis
As in C. extrusa (Figs 4E, 6C), C. darwini (Kuntner & Agnarsson 2010: fig. 6e), C. kuntneri (Figs 6I, 7E), C. mitralis (Grasshoff 1984: figs 19–20, 29–30), C. tinamaze (Gregorič et al. 2015b: fig. 9c), and C. wallacei (Gregorič et al. 2015b: fig. 10c), and in contrast to other Afrotropical species of Caerostris, the epigynal hooks in C. bankana (Fig. 3E) are short rather than long, positioned medially on the epigynal plate rather than anteriorly and pointing laterally rather than posteriorly. As in C. kuntneri but in contrast to the above mentioned species of Caerostris, C. bankana has short and stout epigynal hooks that are about as wide as long, while longer in other species of Caerostris. In contrast to all species of Caerostris, the anterior epigynal margin in C. bankana is S-shaped and perpendicular to the longitudinal body axis (Fig. 3E).
Type material
Holotype
MADAGASCAR • ♀; Nosy Be; SMF3618 SMF.
Description
Female (holotype, Fig. 3A–E)
MEASUREMENTS AND COLORATION. Total body length 23.36. Prosoma 7.81 long, 8.05 wide, 6.97 high. Carapace and chelicerae reddish brown, covered with whitish to yellowish setae. Sternum 3.65 long, 3.46 wide, widest between coxae of second legs, brown with whitish setae. AME diameter 0.40, PME diameter 0.34, AME separation 0.52, PME separation 1.22, PME–PLE separation 3.00, ALE–PLE separation 0.07. Clypeus height 1.48. Appendages: palps brown. All leg segments uniformly reddish brown. Leg I femur 6.53, patella 3.71, tibia 5.51, metatarsus 6.55, tarsus 2.47. Opisthosoma 14.96 long, 14.58 wide, 10.22 high. Base color of dorsum light reddish brown, covered with dark reddishbrown spots, with several small, pointy tubercules on anterior half and pair of large posterior tubercules, pointing posteriorly and protruding past spinnerets. Anterior dorsum with broad, whitish speck. Venter light brown with several dark brown spots, two paler, grey, longitudinal bands. Epigynum as diagnosed (Fig. 3E).
Distribution
Strand (1915) described the female he believed to be collected in Bandar Kwala, North Sumatra, Indonesia. However, the specimen closely resembles Malagasy species in morphology, and at the SMF was kept together with two resembling specimens from Nosy Be, Madagascar. As a similar specimen was never again found in Indonesia, Grasshoff (1984) concluded a confusion of specimen locality the most likely. We agree with this assessment and find Nosy Be, Madagascar as the most likely type locality and known distribution of this species.
Remark
Caerostris bankana Strand, 1915 was synonymized with C. extrusa Butler, 1882 by Grasshoff (1984). In epigynal morphology, the type of C. bankana is clearly different from both C. extrusa and C. kuntneri, as well as all other described species of Caerostris. Due to the lack of molecular data for this species, its phylogenetic position within the genus is unclear.
description: Published as part of Gregorič, Matjaž, Yu, Kuang-Ping, Velez, Winny Rojas & Garb, Jessica E., 2025, Caerostris (Araneidae: Araneae) cryptic diversity highlights the need for taxonomic expertise in the genomic era, pp. 1-23 in European Journal of Taxonomy 989 on pages 6-8, DOI: 10.5852/ejt.2025.989.2877, http://zenodo.org/record/15303757