SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'db6430d322f2bf9ce9279babb6dcf8bd576b1ff3266033735e72f5dc4e5e8f93' 
  AND token = 'uuhYrGgCEBXgr01x1SOzO9Km/defvLNBofXqna+SzkI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}