SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ab43de3761eb3550823da24e2745ace79814a64529eac67b72ee8abc5cafa660' 
  AND token = 'y+QZfBcgYwrjMqKp/B3P5OPkbY3mN0Hn6ect6dBtNic=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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