The control region (D-loop) of mitochondrial DNA (mtDNA) was amplified and sequenced for eight samples of the rhinogobies Rhinogobius maculafasciatus and R. giurinus from Taiwan and southern China. The control regions of both species are of 841-842 bp; the length of these sequences being the most compact among all known sequences in teleost fishes. Three conserved sequence blocks (CSB) were observed. The full D-loop and tRNA Phe gene sequences were determined and compared with other fishes. The interspecific sequence divergence between the two species is 11·3-11·7%; and the intraspecific variation in R. guirinus 0·8-1·8%. Results suggest that the control region of Rhinogobius is informative for phylogenetic reconstruction at both intraspecific and interspecific levels in this gobiid genus. 1998 The Fisheries Society of the British Isles

The control region of the mitochondrial genome was amplified and sequenced for six individuals of the gobioid fish Pomatoschistus minutus, from several European localities, and one specimen of the related Deltentosteus quadrimaculatus. The length of this region for the former species was found to be 773 bp, 7·1% shorter than that previously described as the most compact D-loop known among teleosts. Sequences from other fish have been compared and the largest gap falls in the section between the conserved sequence block and the pyrimidine tract. Alignment of P. minutus sequences was done with D. quadrimaculatus, whose control region length was 853 bp, and this gap was found to be of 61 bp. For the P. minutus sample, the intraspecific sequence divergence is 0·07%.