It can be anything! An apex, subdomain, or even a URL.

Results forapi.turtle.zoocommerce.tech

Logged At	Not Before	Not After	Common Name	Matching Identities	Issuer Name
2019-12-11T06:22:53.638	2019-12-11T05:22:53	2020-03-10T05:22:53	api.turtle.zoocommerce.tech	api.turtle.zoocommerce.tech	C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3
2019-12-11T06:22:53.434	2019-12-11T05:22:53	2020-03-10T05:22:53	api.turtle.zoocommerce.tech	api.turtle.zoocommerce.tech	C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3
2019-10-12T04:26:18.553	2019-10-12T03:26:18	2020-01-10T03:26:18	api.turtle.zoocommerce.tech	api.turtle.zoocommerce.tech	C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3
2019-10-12T04:26:18.38	2019-10-12T03:26:18	2020-01-10T03:26:18	api.turtle.zoocommerce.tech	api.turtle.zoocommerce.tech	C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3