SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '31b23ab81cfc363e6f4976315c3119937227892d72e8030c80ac224334576dc0' 
  AND token = 'Bn/feBIP6VIsxzvPfxq/qHmLOX6Avz9yqIaQseNzDxk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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