Palaeomicromenneus lebanensis Penney, 2003, sp. nov.
Creators: name: Penney, David
Publisher: name: Zenodo
Year: 2023
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Araneae
Salticoididae
Palaeomicromenneus
Palaeomicromenneus lebanensis

description: Palaeomicromenneus lebanensis sp. nov.
Figs. 2, 3.
Holotype and only known specimen: Male, specimen MHNP 723 A preserved in Cretaceous Lebanese amber.
Type horizon: Upper Neocomian–basal Lower Aptian (ca. 125–135 Ma) Cretaceous amber from the Hammana/Mdeyrij outcrop, Lebanon.
Type locality: The outcrop is in Caza Baabda, Mouhafazit Jabal Loubnan (central Lebanon), approximately 45 km WSW of Beirut.
Derivation of the name: The specific epithet is after Lebanon, the provenance of the fossil.
Diagnosis.—The new genus and species is diagnosed by the structure of the male pedipalp: cymbium cup−shaped and without spines, tegulum shallow, appearing as a band of sclerotized tissue between the embolus and cymbium in lateral view. Embolus elongate, tightly coiled three times around the conductor; final coil diameter slightly exceeds that of the cymbium. Distal region of embolus distinctly removed from the main coil and with a slightly constricted bend sub−terminally. Conductor curved and tongue−shaped, extending outwards. Primarily, it differs from extant deinopid genera by having the distal region of the embolus distinctly removed from the main coil and the conductor protruding outwards further than in other genera, to a distance approximately equal to the diameter of the embolic coil.
Description.—Measurements: body length 2.86; carapace 1.29 long, 1.21 at its widest point, narrowed to 0.57 in the ocular region. Carapace with rounded sides and a concave posterior margin. There is a medio−lateral band of pale, feathery setae, which lie flat and run longitudinally (visible on the right side of the carapace when viewed dorsally) (Fig. 2). The band has a slightly “furry” appearance; a corresponding band is not clear on the left side due to flaws in the amber, but is presumed present. The carapace has been damaged during preservation and flaws also obscure the foveal region. Eight eyes: posterior median eyes separated by 0.14, directed forwards and subequal to the posterior lateral eyes, which are slightly wider apart; posterior eye row distinctly recurved (Fig. 3). Posterior median eyes slightly larger than anterior lateral eyes which are on small but distinct cuticular projections (Fig. 2). The left anterior median eye which appears subequal to the anterior lateral eye is just visible between the anterior lateral eye and posteror median eye when the specimen is viewed from above. Detailed structure of chelicerae and mouthparts not visible. Sternum length not measurable but does not extend between fourth coxae, width 0.43, with slight concave invaginations along the sides and covered with feathery setae. Opisthosoma 1.57 long, 1.36 wide, with both normal and feathery setae; the latter more prevalent on the sides of the abdomen. There is no evidence of humps, however, part of the dorsum is missing and in extant species the humps can be reduced in mature males. Cribellum undivided, spinneret region 0.64 wide, as in Fig. 2.
Leg formula 1243 (Figs. 2, 3). Leg 1 coxa 0.50, femur 2.26, patella 0.54, tibia 1.93, metatarsus 2.21, tarsus 1.07, total 8.51; leg 2 coxa 0.41, femur 1.59, patella 0.50, tibia 1.10, metatarsus 1.21, tarsus 0.64, total 5.54; leg 3 coxa 0.21, femur 0.79, patella 0.29, tibia 0.60, metatarsus 0.66, tarsus 0.39, total 2.94; leg 4 coxa 0.29, femur 1.29, patella 0.36, tibia 0.83, metatarsus 1.24, tarsus 0.43, total 4.44. Several long, distinctive spines present on all leg segments except patella 4, which has only one distal spine, and all coxae and tarsi which are spineless (Fig. 3). All segments setose; tibiae, metatarsi and tarsi of all legs with numerous short, thin, erect setae dorsally, retrolaterally, prolaterally and ventrally; feathery setae present on all legs. Femora lack the trichobothria typical of Uloboridae. Femora 2, 3, and 4 ventrally with many long, fine, erect setae that resemble trichobothria but they are not situated in shallow alveoli. Uniseriate calamistrum occupies proximal half of metatarsus 4 (Fig. 2) and in part, lies in a slight cuticular depression. Tarsi with three claws, superior pair with at least six teeth. Tarsus 4 has ventral spines, the tips of these are visible on the right leg; left tarsus 4 is not preserved.
Pedipalp (Fig. 2): femur not elongate, and lacking ventral lobes or other modifications; with one distal, long, curved spine retrolaterally. Cymbium cup−shaped, 0.31 deep and without spines, but covered with long setae. Tegulum shallow, appearing as a band of sclerotized tissue between the embolus and cymbium in lateral view. Embolus elongate, tightly coiled three times around the conductor; final coil 0.64 in diameter, which slightly exceeds that of the cymbium. Distal region of embolus distinctly removed from the main coil and with a slightly constricted bend sub−terminally. Conductor curved and tongue−shaped, extending outwards 0.64.
description: Published as part of Penney, David, 2003, A new deinopoid spider from Cretaceous Lebanese amber, pp. 569-574 in Acta Palaeontologica Polonica 48 (4) on page 571, DOI: 10.5281/zenodo.13391204