SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4db57638aa4eba9a7ee4b359d733ad48a423b07091f8a391dd47bb904a8228de' 
  AND token = 'jGCJjGXzaQ4jgsaYi+t7/wZKH0R6iTN8Z/cnBYzQDuE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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