SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2267c99dc8fec938f7653704f83d1e2853586fe6345c2ca7a8b9b21c39ec1844' 
  AND token = 'h+18pllpDYvshW1KHU2GzNE80xxUgc7m6JmTm+tOq1o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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