Sagittal fracture at the temporal root of the zygomatic arch often occurs as a part of zygomaticomaxillary fractures. The authors described the application of computer-assisted navigation in the lag screw insertion for the fixation of sagittal fracture at the temporal root of zygomatic arch. Using the presurgical planning of the computer-assisted navigation system, the trajectory of lag screw insertion was designed, and the insertion depth was calculated. In the presurgical planning, the trajectory of screw insertion was placed with an anterior inclination of 10° to 15° (mean: 12.24°), and the screw insertion depth was 9.0 to 12.0 mm (mean: 10.65 mm). In the operation, the screw insertion in the fixation of the sagittal fracture was performed under the guidance of navigation system according to the presurgical planning. The postoperative CT scan showed exact reduction and fixation of the sagittal fracture in all cases. Computer-assisted navigation is a useful tool for the lag screw insertion in the precise fixation of sagittal fracture at the temporal root of the zygomatic arch in complex zygomaticomaxillary fractures.

Phyllagathis Blume and Bredia Blume (Sonerileae s.l., Melastomataceae) are two closely related Asian genera with similar morphology and overlapping geographical range. Their generic circumscription and phylogenetic relationships are far from fully understood. We present here a molecular phylogenetic investigation for the two genera using nuclear ribosomal internal transcribed spacer and chloroplast (trnV‐trnM) sequence data. Seventeen genera of Sonerileae s.l. were included in the analyses, with Phyllagathis and Bredia densely sampled to cover their geographical range and morphological diversity. We identified 14 well supported species clusters within Sonerileae s.l.–Medinilla. Phylogenetic analyses together with reconstruction of morphological characters clearly indicated the taxonomic mess in generic delimitation of Sonerileae s.l. Many of the characters traditionally used in generic delimitation were highly homoplasious. Bredia and Phyllagathis, as well as Allomorphia, Anerincleistus, Fordiophyton, and Oxyspora, were revealed to be non‐monophyletic. Bredia, as currently defined, contains two groups of species with different phylogenetic affiliations. Bredia should be recircumscribed to exclude the Bredia–Phyllagathis clade I and accommodate the Bredia–Phyllagathis clade II as the type of the genus is included in the latter clade. Most species sampled in Phyllagathis spread across eight well supported clades throughout the phylogenetic tree. The type of Phyllagathis showed no close affiliation with other members of Phyllagathis nor its putative relatives. Phyllagathis, as presently circumscribed, is heterogeneous, encompassing multiple evolutionary lineages. As sequence data of nuclear ribosomal internal transcribed spacer and chloroplast trnV‐trnM failed to resolve the phylogenetic relationships among these lineages, the formal taxonomic adjustment of Phyllagathis is postponed until further evidence can be gathered.

Background: With three origins of holoparasitism, Orobanchaceae provides an ideal system to study the evolution of holoparasitic lifestyle in plants. The evolution of holoparasitism can be revealed by plastid genome degradation and coordinated changes in the nuclear genome, since holoparasitic plants lost the capability of photosynthesis. Among the three clades with holoparasitic plants in Orobanchaceae, only Clade VI has no available plastid genome sequences for holoparasitic plants. In this study, we sequenced the plastome and transcriptome of Aeginetia indica, a holoparasitic plant in Clade VI of Orobanchaceae, to study its plastome evolution and the corresponding changes in the nuclear genome as a response of the loss of photosynthetic function. Results: The plastome of A. indica is reduced to 86,212 bp in size, and almost all photosynthesis-related genes were lost. Massive fragments of the lost plastid genes were transferred into the mitochondrial and/or nuclear genomes. These fragments could not be detected in its transcriptomes, suggesting that they were non-functional. Most protein coding genes in the plastome showed the signal of relaxation of purifying selection. Plastome and transcriptome analyses indicated that the photosynthesis pathway is completely lost, and that the porphyrin and chlorophyll metabolism pathway is partially retained, although chlorophyll synthesis is not possible. Conclusions: Our study suggests the loss of photosynthesis-related functions in A. indica in both the nuclear and plastid genomes. The lost plastid genes are transferred into its nuclear and/or mitochondrial genomes, and exist in very small fragments with no expression and are thus non-functional. The Aeginetia indica plastome also provides a resource for comparative studies on the repeated evolution of holoparasitism in Orobanchaceae.

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