Orphnaecus libmanan Acuna & Guevarra 2025, sp. nov.

Orphnaecus libmanan Acuña & Guevarra sp. nov. Figs 5, 6, 7, 8 Orphnaecus sp. “L 3” Acuña et al., 2025. Type material. Holotype • ♂ PNM 18867 UST-ARC 0133, field # CSL 02-04, Paratype • ♀ UST-ARC 0132 (field # CSL 02 -03); Philippines: Luzon Island, Bicol Peninsula, Camarines Sur Prov., Libmanan, Brgy. Sigamot, Libmanan Caves National Park; burrows under and inside rotten logs on forest slope near Kalangkawan Cave, 20 Jul 2023, LA Guevarra, DC Acuña, JD Fornillos leg. Paratypes • ♂ ♀, UST-ARC 0130 –0131 (field # CSL 02 -01 – 02); [same locality and natural history data as for holotype]; 20 Apr 2023, LA Guevarra, DC Acuña, CN Noriega, JD Fornillos leg. Paratype • ♀ PNM 18868 UST-ARC 0134. field # CSL 04 -01; [same general locality as for holotype], Brgy. Malinao, Sitio Guimbal, burrow under limestone rock; 20 Apr 2023, LA Guevarra, DC Acuña, CN Noriega, JD Fornillos leg. Paratypes • 3 ♂♂ 3 ♀♀, UST-ARC 0135 –0140 (field # CSL 04 -02 – 07); [same locality data as for the latter], 20 Jul 2023, burrows under piles of coconut husks; LA Guevarra, DC Acuña, JD Fornillos leg. (DCA examined). Type gene sequence. GenBank accessions: PP 778307 – PP 778312 (paratypes). Diagnosis. O. libmanan sp. nov. belongs to the genus Orphnaecus for having reniform lyrate morphology with a row of club-shaped stridulatory setae (Figs 5 G, H, I, 7 H), palpal organ with embolus having basal lobe and PS keel from tip to base (Fig. 6 B – F), presence of palpal scale brush on patellae in males (Fig. 6 A). Females of O. libmanan sp. nov. differ from those of O. kwebaburdeos, O. pellitus, and O. tangcongvaca sp. nov. in having a relatively narrower apex than the base of the spermathecal lobe (SI ~ 44, n = 6; SI> 55 in the mentioned congeners) (Fig. 8 C), in having a greater number of mesoventral denticles with> 100 (n = 6) (<60 in mentioned congeners), and in having relatively longer tarsus I than IV (TI ~ 118, n = 6; T <112 in mentioned congeners). The females further differed from O. kwebaburdeos and O. tangcongvaca sp. nov. in having relatively shorter tibia I than IV (TBI ~ 90, n = 6; TBI> 104 in the mentioned congeners). The females also differed from O. kwebaburdeos in having a relatively shorter leg I than IV (RF ~ 95, n = 6; slightly longer leg I than IV in O. kwebaburdeos females, RF ~ 101). Mature males of O. libmanan sp. nov. differ from mature males of O. adamsoni, O. kwebaburdeos, and O. pellitus in having a relatively shorter embolus than the tegulum (EMI ~ 112, n = 5; EMI> 120 in the mentioned congeners) and longer leg I than IV (RF ~ 102, n = 5; shorter leg I than IV in the mentioned congeners, RF ~ 99). The mature males further differed from O. adamsoni and O. kwebaburdeos in having relatively longer tarsus I than IV (TI ~ 108, n = 5; shorter tarsus I than tarsus IV in the mentioned congeners, TI <93). O. libmanan sp. nov. also differs from O. pellitus and O. tangcongvaca sp. nov. in that it does not exhibit troglomorphism and dwarfism, respectively. Remarks. The female of O. adamsoni Salamanes et al., 2022 was not distinguished from O. libmanan sp. nov. and all known Orphnaecus species because the paratype female is misidentified and misplaced in Orphnaecus. The allotype / paratype ♀ (PNM 14888) used in the original description of the female (Salamanes et al. 2022) is also misplaced in Orphnaecus. Rather, it belongs to Ornithoctoninae because of the presence of a plumose setal field on retrolateral chelicerae, rows of thorn stridulatory setae on the prolateral maxilla, conspicuous white bands on leg segments, and stripe patterns on the dorsal abdomen, which are characteristics absent in Selenocosmiinae but synapomorphic to Ornithoctoninae. This specimen probably represents an undescribed Melognathus species, but a new taxon cannot be assigned to this specimen owing to its poor condition. Other paratype females could potentially be available to the species authors’ institution, but no response has been received to date from our multiple enquiries sent to the first author. Description holotype male. PNM 18867 UST-ARC 0122, field # CSL 02-04, body length 36.02. (Figs 5, 6). Prosoma. Carapace (Fig. 6 A): CL 14.45, CW 12.52, CH 4.72, CR 10.05 long, lateral profile low and flat, and integument matte black. Fovea (Fig. 6 A): width 1.55, curvature at 143 °, procurved. Ocular Tubercle: 1.99 long, 2.6 wide. Eyes (Fig. 6 C): AME round, ALE, PME, and PLE ovoid, clypeus almost absent. AE row almost straight at 176 °, PE row recurved at 139 °. Eye diameters, AME 0.64, ALE 0.67, PME 0.52, PLE 0.56. Interocular distances, AME – AME 0.21, ALE – ALE 1.72, PME – PME 1.31, PLE – PLE 1.87, AME – ALE 0.2, AME – PME 0.13, AME – PLE 0.48, ALE – PLE 0.23, ALE – PME 0.31, PME – PLE 0.07. Chelicerae (Fig. 6 D – F): length 8.32, width 5.20, fang curve length 6.28, teeth 10, mesoventral denticles ~ 40. Cheliceral strikers (Fig. 6 F): primary rows, ~ 13, 0.68–1.07 long, dark long spiniform with filiform ends. Secondary rows, ~ 30, 0.29–0.73 long, dark short spiniform with filiform ends. Tertiary rows, ~ 83, 0.20–0.75 long, pallid tiny needleform. Pseudostrikers, pallid and present ventrally. Maxillae (Fig. 6 G): prolateral maxilla 5.23 long, 3.74 wide laterally, 3.46 wide ventrally. Maxilla prolaterally planoconvex, anterior lobe well pronounced. Maxillary cuspules ~ 272. Lyra (Fig. 6 G, F): lyrate patch 2.33 long, 1.40 high, with a total of ~ 366 stridulatory setae, in 10 or 11 rows, surrounded by fine setae, denser above and distally. Short pointed stridulatory setae (Fig. 6 J, K) ~ 361, 0.12–0.41 long, forming reniform patch, proximally broad. The largest stridulatory setae nine (Fig. 6 H, I), 0.60–0.92 long, situated at the lowest row medially, with the median three are larger and with weakly pointed and well-defined paddle blades, and with stout shaft laterally. Labium: 2.10 long, 2.77 wide, integument reddish brown, anterior 1 / 3 with cuspules ~ 514. Sternum (Fig. 6 B): 7.47 long, 6.83 wide. Sternal corners mildly acuminate, posterior corner acuminate. Labiosternal sigilla 1.20 long, 0.50 wide, 0.40 apart. Sternal sigilla 3 pairs, anterior sigilla 0.33 long, 0.23 wide, 4.47 apart, and 0.40 away from sternal margin adjacent to coxa I, median sigilla 0.93 long, 0.30 wide, 3.57 apart, and 0.63 away from sternal margin adjacent to coxa II, posterior sigilla 1.40 long, 0.53 wide, 1.60 apart, and 1.27 away from sternal margin adjacent to coxa II. Opisthosoma. Abdomen: 13.02 long, 3.97 wide, ovular elongated, integument pale brown. Spinnerets: PMS 2.00 long, 0.59 wide, PLS basal segment 3.15 long, 1.36 wide, median segment 2.05 long, 1.12 wide, apical segment 3.17 long, 0.83 wide. Genitalia. Palpal organ (Fig. 7): length almost 1 / 2 of palp tibia length (POI 46.32). Tegulum 1.96 long, globular, widest medially, prolaterally pronounced, subtegular projection (StR) weakly pronounced. Embolus length 2.19, basal width 0.69, median width 0.21, tip 0.13 wide. Embolus length ~ 1.12 times longer than tegulum length (EMI 111.74), base broad, tapering distally, and curved retrolaterally. Embolus has a long prolateral superior keel (PS) from base to tip, broad basally and at the tip (Fig. 6 B – F); has short and stout prolateral inferior keel (PI), emerged from the tip to rear at around apical 1 / 4, located below PS and embolic opening (Op) (Fig. 6 F); apical keel (A) very short, emerged at the tip (Fig. 6 F); embolic opening (Op) located between PS and PI near the tip (Fig. 6 F). Basal lobe is pronounced and broad (Fig. 7 B – F). Legs. Leg formula 1423. Leg lengths (fem. pat., tib., met., tar. / cym.): palp 26.12 (9.12, 4.84, 8.96, n / a, 3.20), leg I 49.44 (13.19, 7.11, 12.84, 9.73, 6.57), leg II 42.69 (11.94, 5.43, 10.87, 8.96, 5.49), leg III 36.72 (9.43, 4.36, 8.12, 9.08, 5.73), leg IV 48.42 (12.36, 5.43, 11.70, 12.84, 6.09). Leg widths (fem. pat., tib., met., tar. / cym.): palp (2.68, 2.48, 2.76, n / a, 3.24), leg I (3.52, 2.99, 2.51, 1.73, 1.19), leg II (3.22, 2.69, 2.21, 1.31, 1.13), leg III (2.93, 2.39, 1.97, 1.49, 1.19), leg IV (2.87, 2.69, 2.09, 1.31, 1.08). Tarsi III and IV with transverse weakening (cracked or bent), tarsi I and II with no visible weakening. Spines: Metatarsal spines (dorsal-ventral), met. I and II absent, met. III and IV 2, 3. Claws: all tarsal claws with 2 or 3 teeth, tarsus IV with unpaired inferior third claw. Setation. Tactile setae (TS) — carapace entirely with rows of very short brownish-white TS (Fig. 6 A). Carapace margin, dorsal and upper 1 / 2 retrolateral surface of chelicerae, ventral prosoma, opisthosoma, and legs covered with dark and grayish brown, long and short TS, denser on abdomen and all ventral tibiae. Mesoprolateral surface of chelicerae with intercheliceral setae in arcuate strip of rows of setae basally spiniform and anteriorly filiform (Fig. 6 D). Above maxillary suture with rows of short spiniform setae, retrolateral surface smooth with vertical striation on distal 1 / 4 and with rows of fine pallid setae ventrolaterally, and proximal end of prolateral surface with sparse very short spiniform setae. Femoral setation, dark and needleform, intermixed with regular TS. Scales َ — carapace, basodorsal surface of chelicerae, coxae, trochantera, and femora dorsally with pale beige to pale brown cottony and wavy fine scales, proximally grayish-brown on dorsal femora (Fig. 6 A, B, E). Chelicerae, dorsal and upper retrolateral surface, dorsal maxilla, sternum, abdomen, dorsal PLS legs, covered with grayish-brown to grayish white lanceolate flat scales, which reflect purplish blue sheen, except on ventral abdomen and prolateral femora. Palpal scale brush, grayish white, present on patella and tibia, dorsally, very long and dense on patellae (Fig. 6 A). Trichobothria — clavate trichobothria present on all leg tarsi and cymbium, intermixed with epitrichobothria. Epitrichobothria clusters were present on all metatarsi, tarsi, and tibiae. Filiform trichobothria were sparsely present on all dorsal legs. Chemosensory sensilla