SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '13d553167f1ca62a439a847de73c6f085ff58446a0a150be6fefd70da5de2a0b' 
  AND token = 'IaM7PU6DjlHubSv6Ea4kWCypco6fGg6fGjCn+MMrwQ8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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