SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aee4138271d075da36c01a98af149ca37b8a24b88a4284ad4eb72dc651770fd7' 
  AND token = 'bxff/a9eUPaWByVQskz+gfxOQWjiYamBHcTMfnwBKog=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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