A case of persisting massive infection of Scomberomorus commerson, a commercially exploited scombrid fish, with Cybicola armatus (Copepoda: Siphonostomatoida: Pseudocycnidae)

During an extensive survey of fish parasites along the Malabar coast of India we observed exceptionally high or even massive infection of the narrow-barred Spanish mackerel,

Distribution and relative proportions of red muscle in scombrid fishes: consequences of body size and relationships to locomotion and endothermy

The scaling of red muscle with body weight and the distribution of red muscle within the body were compared in seven scombrid fish species to determine relationships between red muscle function and the maintenance of endothermy by tunas. In ectothermic Sarda chiliensis and Scomber japonicus, red muscle occurs along the body edge, is concentrated posteriorly, and the total amount of this tissue is proportional to body weight raised to a power significantly greater than 1.0. In five endothermic tunas, Auxis thazard, Euthynnus lineatus, Katsuwonus pelamis, Thunnus albacares, and T. alalunga, red muscle scaling coefficients are 1.0 or less, and red muscle is positioned deep and anterior in the body. The power needed to overcome drag increases with fish body size (weight and length) and velocity and is reflected in the red muscle scaling relationships of both Sarda and Scomber. By contrast, decreasing relative amounts of red muscle in larger tunas suggest these fishes increase propulsion efficiency as they grow. This may be a result of either or both greater muscle efficiency and reduced division of labor between red and white muscle to which both endothermy and thermoregulation could contribute.

Nematode parasites of Oceanica

Camallanus marinus sp.nov. is described from eleven specimens recovered from a variety of marine fishes. It is the only species in Camallanus s.s. with a single spicule. Spinitectus palawanensis sp.nov. is described from two males and one female found in a scombrid fish. It is characterized by having 12–17 rings of 60–65 spines, a spicule ratio of 5:1, and ten pairs of caudal papillae. Cucullanus lutjani, sp.nov. is described from two specimens from lutjanid fishes. It is distinct in lacking a preanal sucker, in possessing a gubernaculum and eight pairs of cloacal papillae.Oceanicucullanus padfica gen. et sp.nov. is described from two specimens found in cyprinid fish. It is most similar to Indocucullanus, differing from it in the absence of a gubernaculum, and in possessing three pairs of teeth in the radii of the oesophagus. Philometra (Philometra) lateolabracis Yamaguti, 1935; Terranova sp.; and Procamallanus spp. are reported for the first time in the Philippines.We wish to thank Dr D. S. Rabor, Silliman University, Damageute, Negros Oriental, Republic of the Philippines, for general support in field activities, and Dr Loren Wood, Curator of Fishes, and Dr Robert F. Inger, Curator of Reptiles, Chicago Museum of Natural History, for identification of hosts. Acknowledgement is also made to Dr Betty June Myers for technical assistance and advice in handling materials.