SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5d668bb8891d2392f733db2721ce005982bbeed48d6bac768ac4ea61d4ef6129' 
  AND token = '2aQqqYO1pbUrX7KSglJU+iX6jHJFAsNmnX95lxh94v8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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