SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '811a7d42f967b53a7a16a3fa68c4ef46279ba2cba9b705b0e57c79f424c10d4e' 
  AND token = 'Kdq5s/tOjyHcwHmwkUZXKK3ljS2pq7BboVas2hUvQvk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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