SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '46d1bbdaa2a0399d07e8d7060aa109fbd3f5815c3afa3f483e4ee6afd75a61b8' 
  AND token = 'XK1Z7cwKePlhITjNDXEfyboviefzRfxjpbxoyiccuaA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}