A lighting device in the form of a light module for a motor vehicle headlight or in the form of a motor vehicle headlight, which lighting device comprises at least one optical body, which has a number of adjacently arranged ancillary optical systems (11, 12, 13, 14, 15), wherein each ancillary optical system is formed from a light-guiding material and each ancillary optical system has a light coupling-in face (11a-15a) and a light decoupling face (11b-15b), wherein the ancillary optical systems are mechanically interconnected in the region of the light decoupling faces (11b-15b) by at least one connecting web (21, 22) extending transversely to the ancillary optical systems, and wherein a mounting device for the at least one optical body is provided, and wherein the mounting device *) comprises a main body, which can be connected to a support for one or more light sources for feeding light into the optical body, wherein the main body has at least one receptacle (111, 112, 113, 114, 115) for the ancillary optical systems, and wherein the main body also has at least one stop region (121, 122), with which the optical body can be brought into abutment via a rear face (21', 22') of the at least one connecting web (21, 22) when the ancillary optical systems are inserted into the at least one receptacle (111,112,113,114,115), characterised in that the at least one connecting web (21, 22) is optically ineffective, at least in some regions, and the mounting device *) has a retaining body, which, once the optical body has been introduced into the main body, can be applied to the main body in the direction of introduction of the optical body, wherein a fastening device (101a, 102a) is provided, by means of which the retaining body can be fixed to the main body, and wherein *) the retaining body has at least one, preferably precisely one opening, such that light can exit unhindered from the light decoupling faces (11b-15b) of the ancillary optical systems, and wherein *) the retaining body has clamping elements which, when the retaining body is fastened to the main body, come to rest against the at least one connecting web (21, 22) on the front face thereof (21", 22"), and wherein *) one or more ancillary optical systems has/have webs (11b", 12b", 13b", 14b", 15b"), which extend the light decoupling faces (11b-15b) of these ancillary optical systems, wherein each web (11b", 12b", 13b", 14b", 15b") is arranged in a region of the light decoupling face (11b, 12b, 13b, 14b, 15b) facing away from the connecting web (21, 22) connecting the ancillary optical system in question to other ancillary optical systems, and wherein the retaining body has clamping elements which, when the retaining body is fastened to the main body, come to rest against the web or these webs (11b", 12b", 13b", 14b", 15b") of the one or more ancillary optical systems, and the clamping elements (102b, 102c) press the optical body against the at least one stop region (121,122) of the main body. *) comprises a main body, which can be connected to a support for one or more light sources for feeding light into the optical body, wherein the main body has at least one receptacle (111, 112, 113, 114, 115) for the ancillary optical systems, and wherein the main body also has at least one stop region (121, 122), with which the optical body can be brought into abutment via a rear face (21', 22') of the at least one connecting web (21, 22) when the ancillary optical systems are inserted into the at least one receptacle (111,112,113,114,115), characterised in that the at least one connecting web (21, 22) is optically ineffective, at least in some regions, and the mounting device *) has a retaining body, which, once the optical body has been introduced into the main body, can be applied to the main body in the direction of introduction of the optical body, wherein a fastening device (101a, 102a) is provided, by means of which the retaining body can be fixed to the main body, and wherein *) the retaining body has at least one, preferably precisely one opening, such that light can exit unhindered from the light decoupling faces (11b-15b) of the ancillary optical systems, and wherein *) the retaining body has clamping elements which, when the retaining body is fastened to the main body, come to rest against the at least one connecting web (21, 22) on the front face thereof (21", 22"), and wherein *) one or more ancillary optical systems has/have webs (11b", 12b", 13b", 14b", 15b"), which extend the light decoupling faces (11b-15b) of these ancillary optical systems, wherein each web (11b", 12b", 13b", 14b", 15b") is arranged in a region of the light decoupling face (11b, 12b, 13b, 14b, 15b) facing away from the connecting web (21, 22) connecting the ancillary optical system in question to other ancillary optical systems, and wherein the retaining body has clamping elements which, when the retaining body is fastened to the main body, come to rest against the web or these webs (11b", 12b", 13b", 14b", 15b") of the one or more ancillary optical systems, and the clamping elements (102b, 102c) press the optical body against the at least one stop region (121,122) of the main body.