SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8525dddd2a7f69e38ea53568a02c5f18d73ce4851c73e91ce6bf75a694b1c0ac' 
  AND token = 'pioYFdWbbQ+wicQvVDPvynpNi/egn5hfHo7N+KwyOxk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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