FISHES OF FAMILY BLENNHDAB 55 



Gosline's six hypurals is considered a haemal spine and there remain 

 only five independent hypurals. 



In establishing a basal blennioid (suborder Blennioidei) stock, 

 Gosline (1968) believes that the Acanthoclinidae or Opisthognathidae 

 are the most primitive members. Figure 14 is an illustration of the 

 caudal fin of Acanthoclinus species from New Zealand. This caudal 

 fin, while considerably advanced over the most primitive perciform 

 caudal, serves as a basis for interpretation of the blenniid caudal. 

 The caudal of Acanthoclinus has: 14 branched caudal rays; three 

 epurals; no independent uroneural ossifications (these apparently 

 are fused to the urostyle); a single urostyle ossification to which 

 is fused an indistinguishable hypural plate probably consisting of 

 hypurals 3 and 4; an independent hypural 5 dorsal to the fused 

 hypural plate and urostyle; an independent fused ventral hypural 

 plate consisting probably of a haemal spine and hypurals 1 and 2 

 (in addition, this plate exhibits the hooklike process on the haemal 

 spine portion that is common in primitive perciforms and to which 

 the flexor caudalis ventralis superficialis muscle attaches); and the 

 haemal arches of the two vertebrae ahead of the urostylar vertebra 

 fused to their centra. The blenniid caudal is considerably more 

 specialized than that of Acanthoclinus. Differences are, for the most 

 part, the result of more fusions and the loss of some elements. 



The caudal fin of the Blenniinae is typically rounded with the 

 longest rays on the ventral half of the fin. Atrosalarias, Ecsenius 

 (both Salariiui), and Omohranchus (Omobranchiui) are exceptions 

 m that the adults may have the upper and lower rays greatly pro- 

 duced and the tips of the other rays may extend beyond the margin 

 of the inter-radial membrane. The caudal of the Nemophidinae is 

 shaped similar to that of the Blenniiuae, but many of the species 

 have the caudal rays produced as in the three genera listed above. 



The number of segmented caudal fin rays in blenniids varies 

 from 10 (Xiphasia and rarely Atrosalarias) to 15 in Omohranchus 

 lini (the range in 0. lini is from 13 to 15 with no sharp mode). The 

 usual number of segmented rays is 11 in the Nemophidinae and 

 13 in the Blenniinae, but some genera or species of the latter have 

 different counts: Chasmodes, 11 to 12; Ecsenius hicolor and Praealticus 

 margaritatus, 14; Andamia, Damania, Alticus and Lophalticus, 12; 

 Atrosalarias, 10 to 14, usually 12 or 13 (rays unbranched in all these 

 taxa). A variation of one ray from the modal number in specimens 

 of any species is not uncommon. The caudal rays may all be simple 

 (all Nemophidiuae, all Omobranchini except individual variants 

 with one or two branched rays, Medusahlennius chani of the Blenniini, 

 and many genera of the Salariini, listed above) or some may be 

 branched (most Blenniini and Salariini). The caudal rays are never 

 branched more than once. In species with blanched caudal rays, 



