- hosts: test
  roles:
    - role: base

- name: base
  src: ssh://git@10.0.0.1/ansible/role-base.git
  scm: git

galaxy-info:
  author: Me
  description: Test Ansible role dependencies
  min_ansible_version: 1.9
  platforms: Ubuntu
dependencies:
  - name: dep
    src: ssh://git@10.0.0.1/ansible/role-dep.git
    scm: git

$ ansible-galaxy -r requirements.yml
- executing: git clone ssh://git@10.0.0.1/ansible/role-base.git base
- executing: git archive --prefix=base/ --output=/tmp/tmp4YKG7a.tar
- extracting base to ansible-roles/base
- base was installed successfully
- adding dependency: dep
- executing: git clone ssh://git@10.0.0.1/ansible/role-dep.git dep
- executing: git archive --prefix=dep/ --output=/tmp/tmpT2YiW4.tar
- extracting base to ansible-roles/dep
- dep was installed successfully

$ ansible-playbook play.yml
ERROR: expected a role name in dictionary: {'scm': 'git', 'src': 'ssh://git@10.0.0.1/ansible/role-dep.git', 'name': 'dep'}

dependencies:
  - role: "git+ssh://git@10.0.0.1/ansible/role-dep.git,,dep"

$ ansible-galaxy -r requirements.yml
- executing: git clone ssh://git@10.0.0.1/ansible/role-base.git base
- executing: git archive --prefix=base/ --output=/tmp/tmpTcvpDu.tar
- extracting base to ansible-roles/base
- base was installed successfully
- adding dependency: dep
- executing: git clone ssh://git@10.0.0.1/ansible/role-dep.git dep
- executing: git archive --prefix=dep/ --output=/tmp/tmpd726OV.tar
- extracting base to ansible-roles/dep
- dep was installed successfully

$ ansible-playbook play.yml
ERROR: cannot find role in <pwd>/roles/git+ssh://git@10.0.0.1/ansible/role-dep.git,,dep or <pwd>/git+ssh://git@10.0.0.1/ansible/role-dep.git,,dep or <pwd>/ansible-roles/git+ssh://git@10.0.0.1/ansible/role-dep.git,,dep