Geogaranya valiyaensis, Agnihotri & Singh & Subramanian & Vishwanathan & Abstract, 2024

Agnihotri, Priya, Singh, Hukam, Subramanian, Kumarapuram A., Vishwanathan, Jagannadh & Abstract, Ashok Sahni, 2024, A new genus and species of fossil pseudoscorpion (Arachnida: Pseudoscorpiones) from the Eocene amber of Western India, Palaeontologia Electronica (a 26) 27 (2), pp. 1-14 : 5-8

G. valiyaensis sp. nov. ♂

Figures 1 , 3 , 4

zoobank.org/ 53588E48-742C-485E-9CE3-7B23C3B93E1B

Type material. BSIP museum no. 41982; a geogarypid adult pseudoscorpion, well-preservedin amber resin.

Locality. Valia Lignite Mine , Cambay Basin, Gujarat.

Age. early Eocene

Etymology. Genus name derived from the Indian Geogarypus and Aranya, meaning “wilderness” '

in sanskrit; the specific epithet named after Valia Lignite Mine.

Diagnosis. G. valiyaensis gen. nov. sp. nov. differs from the other genera of family Geogarypidae in possessing carapaceal alae, smallest size, triangular carapace, eyes on ocular tubercles, exceptionally long chelal fingers, non-clavate bristles, distinctly granulated prosoma, and articulation differences between appendages.

Genus description. Prosoma-chelal fingers with 5-6 pair of setae, no teeth on movable fingers, tarsal claws absent, prosoma coarsely granulated, flagellum with minute bristles, ovate chelicerae, no tubercles lining the thorax, non-clavate bristles unlike other genera; opisthosoma- male sternites without margins, pitted surface lining the Ist tergite, tergites II-VI with prominent keels, spiracles and tarsal setae absent; appendages-articulation difference between front, mid and hind legs unlike the heterofemorate articulation found in other genera of Family Geogarypidae .

Species description. Smallest known adult ( Figure 1 ), well preserved in Cambay amber, length from chelicerae to abdomen 0.60 mm, flattened, pear-shaped body, chelicerae rather short, distal blades with serrations, prosoma 0.16 mm, longer than broad, sub-rectangular, granular pattern over the carapace, antero-marginal position of eyes, pedipalps 0.8 mm (L and R each), twice the length as the abdomen, smooth chelae including movable fingers, no teeth overmovable fingers, numerous setae on the dorsal chelal surface ( Figure 4A ), trochanter 0.06 mm (L and R each), femur 0.20 mm (L), 0.23 mm (R), elongate, patella 0.10 mm (L), 0.16 mm (R), chela without pedicel, 0.40 mm (L), 0.41 mm (R), swollen, trichobothria indistinguishable, carapace granular with minute setae, opisthosma 0.36 mm, ovate, marked segmentation ( Figure 3C, D ), twelve opisthosomal segments visible, I-XII tergites visible, median suture lines dividing each tergite longitudinally, numerous lyrifissures, no terminal stinger, spiracles absent, legs poorly preserved ( Figure 4C ), broken, leg 1 (L) detached from the body, coxae attached with the thorax of leg I (R), II (L, R), III (L, R) and IV (L, R).

Remarks. G. valiyaensis gen nov. sp. nov. in amber adds major insights into the evolution of the pseudoscorpion taxa and contributes to the diverse amber arthropod community found in the Cambay Basin of Gujarat. The fossil implies a much warmer temperature, with its assimilation of distinct characteristics, akin to fauna in a warm-temperate biome. We also find similar affinities of the fossil with those recorded from the Baltic and Bitterfeld, in support of a strong tilt towards bark-dwelling taxa ( Harms and Dunlop, 2017).

Figures

FIGURE 1. Geogaranya valiyaensis n. gen., n. sp. ♂ (dorsal view), BSIP Museum Number- 41982.

FIGURE 3. High resolution images (A and C- under stereoscope M205A, B and D- SEM images) of characteristic details of Geogaranya valiyaensis. (A) and (B) granular projections on cephalothorax (dorsal view), (C) and (D) tergites III to VI with lyrifissures (magnified dorsal view).

FIGURE 4. High resolution images of details of Geogaranya valiyaensis. (A) Chelal fingers (L and R) with long setae (magnified view), (B) pedipalps (L and R), (dorsal view), (C) fair preservation of tarsi on fore- and midleg (L).