Then ask that you post your load order so that I can check to see what you are using, have you tried using the MMM Version instead? Have you tried moving No Spider lower down in load order before spawn rate plugin if using any?
The Spider Dryad and Dwemer Spider are still play has they are not considered spiders once again. With the dwemer being more machine like..
It was definitely a large furry spider resembling a Tarantula. I encountered it outside not far from Lleyowin IIRC. I have not tried using the MMM - No spiders plugin because it says in the documentation to always use the FCOM plugins over another mod's that does the same thing. For the moment I have not changed its place in the load order.
00 Oblivion.esm
01 MathFunctions.esm
02 Francesco's Leveled Creatures-Items Mod.esm
03 Francesco's Optional New Items Add-On.esm
04 Oscuro's_Oblivion_Overhaul.esm [Version 1.34]
05 Mart's Monster Mod.esm [Version 3.7b3p3]
06 TamrielTravellers.esm [Version 1.39c]
07 BetterMusicSystem.esm
08 FCOM_Convergence.esm [Version 0.9.9MB3]
09 Kvatch Rebuilt.esm
0A HorseCombatMaster.esm
0B Unofficial Oblivion Patch.esp [Version 3.2.4]
0C DLCShiveringIsles.esp
0D Unofficial Shivering Isles Patch.esp [Version 1.4.0]
0E Francesco's Optional Chance of Stronger Bosses.esp
0F Francesco's Optional Chance of Stronger Enemies.esp
10 Francesco's Optional Chance of More Enemies.esp
11 Francesco's Optional Leveled Guards.esp
12 Francesco's Dark Seducer Weapons Patch.esp
13 FCOM_Francescos.esp [Version 0.9.9]
14 FCOM_FrancescosItemsAddOn.esp [Version 0.9.9]
15 FCOM_FrancescosNamedBosses.esp [Version 0.9.9]
16 aaaJNF-&-DS-Pirate-Isles-Beta.esp [Version 1.0]
17 oc_darker_nights.esp
18 Enhanced Water v2.0 HD.esp
19 Better Bell Sounds.esp
1A Symphony of Violence.esp
1B AmbientTownSounds.esp
1C Stormier storms.esp
1D ChaseCameraMod.esp
1E Days&Months.esp
1F Enhanced Economy.esp [Version 3.4.3]
20 DLCHorseArmor.esp
21 DLCHorseArmor - Unofficial Patch.esp [Version 1.0.5]
22 DLCOrrery.esp
23 DLCOrrery - Unofficial Patch.esp [Version 1.0.3]
24 DLCVileLair.esp
25 DLCVileLair - Unofficial Patch.esp [Version 1.0.5]
26 DLCMehrunesRazor.esp
27 DLCMehrunesRazor - Unofficial Patch.esp [Version 1.0.4]
28 DLCSpellTomes.esp
29 DLCSpellTomes - Unofficial Patch.esp [Version 1.0.1]
2A DLCThievesDen.esp
2B DLCThievesDen - Unofficial Patch.esp [Version 1.0.5]
2C DLCThievesDen - Unofficial Patch - SSSB.esp [Version 1.0.4]
2D Francesco's No Reduced Backwards Running.esp
2E ExnemRuneskulls.esp
2F FCOM_ExnemRuneskulls.esp [Version 0.9.9]
30 Slof's Oblivion Robe Trader.esp
31 Bob's Armory Oblivion.esp
32 FCOM_BobsArmory.esp [Version 0.9.9]
33 Loth's Blunt Weapons for Npcs.esp
34 FCOM_LothsBluntWeapons.esp [Version 0.9.9]
35 Oblivion WarCry EV.esp
36 FCOM_WarCry.esp [Version 0.9.9MB3]
37 Oscuro's_Oblivion_Overhaul.esp [Version 1.34]
38 OOO-Water_Weeds.esp [Version 1.33]
39 OOO-Map_Markers_Stock.esp [Version 1.33]
3A OMOBS.esp [Version 1.0]
3B FCOM_Convergence.esp [Version 0.9.9Mb3]
3C FCOM_EntropicOrderRebalance.esp [Version 0.9.9beta2]
3D FCOM_RealSwords.esp [Version 0.9.9]
3E FCOM_SpawnRatesReduced.esp [Version 0.9.9Mb3]
3F Mart's Monster Mod - More Wilderness Life.esp [Version 3.7b3p3]
40 FCOM_SaferRoads.esp [Version 0.9.9]
41 FCOM_LessRats.esp [Version 0.9.9]
42 FCOM_NoSpiders.esp [Version 0.9.9]
43 FCOM_NoAdventurersInGates.esp [Version 0.9.9]
44 Mart's Monster Mod - Looting NPCs & Creatures.esp [Version 3.7b3p3]
45 Mart's Monster Mod - No Reavers.esp [Version 3.7b3p3]
46 Mart's Monster Mod - No Bone Loot.esp [Version 3.7b3p3]
47 Mart's Monster Mod - No Undead Rise.esp [Version 3.7b3p3]
48 Mart's Monster Mod - No Werewolves.esp [Version 3.7b3p3]
49 Mart's Monster Mod - Safer Quest Locations.esp [Version 3.7b3p3]
4A Mart's Monster Mod - Dungeons of MMM.esp [Version 3.7b3p3]
4B Mart's Monster Mod - Farm Animals.esp [Version 3.7b3p3]
4C Mart's Monster Mod - Diverse WaterLife.esp [Version 3.7b3p3f]
4D Mart's Monster Mod - Diverse Runeskulls Loot.esp [Version 3.7b3p3]
4E TamrielTravellers4OOO.esp [Version 1.39c]
4F ShiveringIsleTravellers.esp [Version 1.39c]
50 FCOM_TamrielTravelers.esp [Version 0.9.9]
51 FCOM_DiverseGuardUnity.esp [Version 0.9.9]
52 FCOM_BobsGuardUnity.esp [Version 0.9.9]
53 FCOM_HungersUnitySI.esp [Version 0.9.9]
54 FCOM_Archery.esp
55 FCOM_Archery_RealSwords.esp
56 Mart's Monster Mod - Shivering Isles.esp [Version 3.7b3p3]
57 Crowded Cities 30.esp
58 Extended Imperial City Version 1.0.esp
59 Extended Chorrol.esp
5A Extended Skingrad.esp
5B Kvatch Rebuilt.esp
5C Kvatch Rebuilt - OOO Compatibility.esp
5D Kvatch Rebuilt - Leveled Guards - FCOM.esp
5E Cyrodiil Travel Services.esp [Version 1.3]
5F za_bankmod.esp
60 DLCBattlehornCastle.esp
61 DLCBattlehornCastle - Unofficial Patch.esp [Version 1.0.4]
62 DLCFrostcrag.esp
63 Knights.esp
64 Knights - Unofficial Patch.esp [Version 1.0.9]
65 RTT.esp
66 Blood&Mud.esp
67 Blood&Mud - EE patch.esp [Version 1.0]
68 Mart's Monster Mod - City Defences.esp [Version 3.7b3p3]
69 FCOM_Blood&Mud.esp [Version 0.9.9]
6A FCOM_Knights.esp [Version 0.9.9Mb3]
6B FCOM_Ruin.esp [Version 0.9.9]
6C FCOM_SlofsRobeTrader.esp [Version 0.9.9]
6D xuldarkforest.esp [Version 1.0.4]
6E xulStendarrValley.esp [Version 1.2.2]
6F xulTheHeath.esp
70 MMMMWL-TheHeath patch.esp
71 XulEntiusGorge.esp
72 xulFallenleafEverglade.esp [Version 1.3.1]
73 xulColovianHighlands_EV.esp [Version 1.2.1]
74 xulChorrolHinterland.esp [Version 1.2.2]
75 xulBeachesOfCyrodiilLostCoast.esp [Version 1.6.3]
76 xulBravilBarrowfields.esp [Version 1.3.2]
77 xulLushWoodlands.esp [Version 1.3]
78 xulAncientYews.esp [Version 1.4.2]
79 xulAncientRedwoods.esp [Version 1.6]
7A xulCloudtopMountains.esp [Version 1.0.3]
7B xulArriusCreek.esp [Version 1.1.3]
7C xulPatch_AY_AC.esp [Version 1.1]
7D xulRollingHills_EV_withoutWheat.esp [Version 1.3.2]
7E MMMMWL-RollingHills patch.esp
7F xulPantherRiver.esp
80 xulRiverEthe.esp [Version 1.0.2]
81 xulBrenaRiverRavine.esp [Version 1.0.2]
82 xulImperialIsle.esp [Version 1.6.3]
83 xulBlackwoodForest.esp
84 xulCheydinhalFalls.esp [Version 1.0.1]
85 Blood&Mud-CheydinhalFalls patch.esp
86 KvatchRebuilt-CheydinhalFalls patch.esp
87 xulAspenWood.esp [Version 1.0.1]
88 xulSkingradOutskirts.esp
89 BarrowFields-Blood&Mud-Patch.esp [Version 1.3]
8A Blood&Mud-PantherRiver patch.esp
8B JQ-Fighters_Guild_United.esp
8C Harvest [Flora].esp [Version 3.0.0]
8D Harvest [Flora] - Shivering Isles.esp [Version 3.0.0]
8E Harvest [Flora] - DLCVileLair.esp [Version 3.0.0]
8F Harvest [Flora] - DLCFrostcrag.esp [Version 3.0.0]
90 P1DkeyChain.esp [Version 5.00]
91 Enhanced Economy - House prices.esp [Version 1.0]
92 LTDVampireOverhaul.esp
93 attack and hide harder v2.1.esp
94 No psychic guards harder fix.esp
95 Denock Arrows.esp
96 No More Annoying Comments.esp
97 MM_NoMoreAnnoyingMessages-Lite.esp
98 Francesco's 14 days respawn time - 1-24 day lenght rescale.esp
99 Real Lava 1.3.esp
9A Mark & Recall.esp
9B Bashed Patch, 0.esp
9C DeadlyReflex 5 - Combat Moves.esp
Perhaps "Francesco's 14 days respawn time - 1-24 day lenght rescale.esp" should load earlier?