SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4470bf832ebb736e11175fb88a1a7f9e4c5b25a000d93d3a2d40fbb511949e5f' 
  AND token = 'KynckhhXu8gFWoNqiQVuc3A4hG8CJIrmCYbElbA4Wd8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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