The morphology of 21 exocrine glands and 13 supposedly exocrine structures recorded for lepidopteran larvae is reviewed. The epitracheal glands, for which a double role (exocrine and endocrine) has been demonstrated, are examined as well. Function is well known for at least 8 glands but completely unknown for 6 glands, for 10 putative glandular structures, and for the exocrine component of the epitracheal glands. Functional studies on the remaining structures are insufficient; in some cases (mandibular gland and adenosma) homologous glands may play a different role depending on the species, and only a few taxa have been examined. The secretions of 13 glandular types have been analyzed chemically. The histology of 11 glands is known at the ultrastructural level, whereas that of 6 glands and 7 putative glandular structures is completely unknown. Comparative anatomical studies of the osmeterium, adenosma, and Verson's glands may yield useful information for phylogenetic reconstructions.

Abstract. The external morphology and chaetotaxy of the larvae of Heterogynidae (Lepidoptera) are described in order to provide information of potential phylogenetic value for the reconstruction of the systematic relationships within the Zygaenoidea. The most outstanding characteristics of heterogynid larvae are their modified habitus during diapause, the presence of an epipharyngeal lamella, the shape of the prothoracic shield, the presence in the first instar of an organ of unknown function on the middorsum of the mesothorax ("Chapman's organ"), the absence of V2, V3 and Va on the head, the absence of V1 on the prothorax and the presence of two primary setae on the inner side of the proleg, the last trait representing an autapomorphy of the family. A number of possible synapomorphies with the Zygaenidae (e.g. presence of cuticular cavities) suggest a close relationship between these two families, but other larval and adult traits are shared only with the "Phaudinae" and limacodid-group families of the Zygaenoidea (viz. absence of V1 on the prothorax with the "Phaudinae", reduced proboscis and absence of ocelli with them all). Nevertheless, a lack of knowledge of the preimaginal instars of species from some zygaenoid families, and of the homology and polarity of given characters of groups within and outside the Zygaenoidea, hamper a thorough comparison of larvae.

 AbstractVegliante, F. 2005. Larval head anatomy of Heterogynis penella (Zygaenoidea, Heterogynidae), and a general discussion of caterpillar head structure (Insecta, Lepidoptera). -Acta Zoologica (Stockholm) 86 : The internal head anatomy (and the peculiar integumental structure of the epicranial notch region) of Heterogynis penella larvae are described; special attention is paid to the skeleto-muscular and nervous systems and to the cephalic glands. Transverse ligaments connect the apodemes of the mandibular adductor muscles of both sides and the anterior maxillo-labial articulations of both sides. The two ligaments are linked to each other by a thin, apparently acellular membrane. An accessory, trilobed mandibular gland is present. A putative stretch receptor, connecting the oblique dorsal cibarial dilators of both sides, is described for the first time in a lepidopterous larva and its importance in assessing the homology of these muscles is discussed. The presence of cibarial sensilla, previously predicted in other caterpillars on the basis of behavioural experiments and observations of the nerve pattern, is confirmed. The structural diversity of larval head anatomy in ditrysian Lepidoptera is discussed, with particular emphasis on the innervation of the corpora cardiaca and corpora allata and of the sensilla of the head capsule.