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Gilen gen. nov. (type species G. orientalis sp. nov.) from South East Asia is described and illustrated. The new taxon has a produced mid-longitudinal facial projection, which differentiates it from all other known genera of Ichneumonidae. It belongs to the tribe Perilissini in the subfamily Ctenopelmatinae (Hymenoptera, Ichneumonidae) and is recorded from Laos, Northern Thailand and Vietnam. [ABSTRACT FROM AUTHOR]

Facial prognathism and projection are important characteristics in human evolution but their three-dimensional (3D) architectonic relationships to basicranial morphology are not clear. We used geometric morphometrics and measured 51 3D-landmarks in a comparative sample of modern humans ( N = 78) and fossil Pleistocene hominins ( N = 10) to investigate the spatial features of covariation between basicranial and facial elements. The study reveals complex morphological integration patterns in craniofacial evolution of Middle and Late Pleistocene hominins. A downwards-orientated cranial base correlates with alveolar maxillary prognathism, relatively larger faces, and relatively larger distances between the anterior cranial base and the frontal bone (projection). This upper facial projection correlates with increased overall relative size of the maxillary alveolar process. Vertical facial height is associated with tall nasal cavities and is accommodated by an elevated anterior cranial base, possibly because of relations between the cribriform and the nasal cavity in relation to body size and energetics. Variation in upper- and mid-facial projection can further be produced by basicranial topology in which the midline base and nasal cavity are shifted anteriorly relative to retracted lateral parts of the base and the face. The zygomatics and the middle cranial fossae act together as bilateral vertical systems that are either projected or retracted relative to the midline facial elements, causing either midfacial flatness or midfacial projection correspondingly. We propose that facial flatness and facial projection reflect classical principles of craniofacial growth counterparts, while facial orientation relative to the basicranium as well as facial proportions reflect the complex interplay of head-body integration in the light of encephalization and body size decrease in Middle to Late Pleistocene hominin evolution. Developmental and evolutionary patterns of integration may only partially overlap morphologically, and traditional concepts taken from research on two-dimensional (2D) lateral X-rays and sections have led to oversimplified and overly mechanistic models of basicranial evolution. [ABSTRACT FROM AUTHOR]

The basicranium and face have been linked through genetic, developmental, and functional relationships throughout their evolution. As a result, basicranial morphology most likely plays a major role in the evolution of facial structures. We describe the relationships between basicranial flexion and the face in Homo, Pan, and Gorilla to determine the role of cranial base angle reduction in the setup of the short and orthognathic face of Homo. We test the hypotheses that cranial base flexion plays a significant part in variation in facial orientation, length, and projection at the intraspecific level. The sample comprised 125 crania of adult specimens including 66 Homo sapiens, 32 Pan troglodytes, and 27 Gorilla gorilla. We described the cranial base and face using landmarks placed on scans of the surfaces and computed correlations between the cranial base angle and facial orientation, length, and projection. Our results support the hypotheses that cranial base flexion plays a significant part in facial orientation for Homo and Pan and in facial length for Pan. The hypothesis that basicranial flexion is related to a reduction of facial projection is not supported. The findings suggest that basicranial flexion can explain several anatomical specificities of hominins, including the reduction of prognathism and the reduction of the length of the nasopharynx. We found different patterns in the different genera, highlighting the fact that changes in the relationship between craniofacial structures may have occurred during hominid evolution. [ABSTRACT FROM AUTHOR]