SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '99b8cc6804379d15a6c55f7a050a5c93820755fb8465fbf95c716dff533910c1' 
  AND token = 'yj9WJ5Qz8tZtyWCJnC0EZw9z0DBSp6WqDPWtuHgByUU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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