SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6fc964346d871c3b7caffcf520050b77c037bbb316925bf48eff7d0a227fc04f' 
  AND token = 'GKD/BRZU5XX7qKEQXoqIjUJN4ZbA4gm1W3iALQXYd6Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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