603

Rapp. P.-v. Réun. Cons. int. Explor. Mer, 178: 603-604. 1981.

CURRENT KNOWLEDGE OF NORTHEAST PACIFIC SCULPIN LARVAE (PISCES: COTTIDAE AND ALLIES) WITH NOTES ON RELATIONSHIPS WITHIN THE GROUP

S a l l y L. R i c h a r d s o n Gulf Coast Research Laboratory East Beach Drive, Ocean Springs, Mississippi 39564, USA

EXTENDED SUMMARY Table 1. Cottid genera reported to occur in the northeast Pacific between Baja California and the Aleutian Islands. (* indicates Cottids1 are a diverse group of temperate and boreal genera for which larvae are known.) fishes. Nelson (1976) estimated the group may contain about 350 species, three-fourths of which are marine, A rrediellus * Hemitripterus Poroeottus in 86 genera. They are generally coastal fishes * Artedius * Icelinus * Psychrolutes inhabiting all oceans but the Indian. Greatest species Ascelichthys *Icelus * Radulinus diversity occurs in the North Pacific Ocean. Asemichthys Jordania * Rhamphocottus * Scorpaenichthys In the northeast Pacific between Baja California * Blepsias Leiocottus Sigmistes and the Aleutian Islands, 40 cottid genera (Table 1) *Chitonotus * Leptocottus * Malacocottus Stelgistrum containing 90 species are reported to occur. With the * Clinocottus * Myoxocephalus Sternias recent work by Richardson and Washington (1980) *Cortus * Dasycottus * Nautichthys Stlegicottus larvae are now known for representatives of 25 of these * Enophrys * Oligocottus Synchirus 40 genera (Table 1), although two genera, Eurymen * Orthonopias Thyrisicus Gymnocanthus and Icelus are represented only by * Gilbertidia * Paricelinus * Triglops species from other areas. In the paper (abstracted here) * Gymnocanthus Phallocottus Zesticelus this information is summarized in tabular form for 46 *Hemi!epidotus species listing references and sizes of larvae illustrated in the literature. The present state of cottid systematics is confused. Knowledge of these larval forms provides a basis for Some taxonomic problems are still in need of summarizing important larval characters within the resolution and relationships within the group are not cottids. Cottid larvae exhibit a wide diversity of form. well understood. Because of this situation and because The most outstanding larval characters, excluding larvae are now known for 25 of 40 northeast Pacific meristics, are preopercular spine pattern, body shape, genera, a preliminary examination of groupings based and pigmentation. Preopercular spines typically on larval characters is attempted which in turn may number four. Variations include four main spines with provide insights into relationships and evolutionary one or two auxiliary spines, only one spine, no spines, trends. or multiple spines numbering up to-'-25. General body Illustrations of larvae of 32 species are included in shape can range from rather stubby, deep-bodied the paper representing 25 identified genera and one forms to moderately slender, elongated forms to potentially new northeast Pacific genus identified only globose. The snout can be quite rounded or pointed. as Cottoid Type A. Six groups of genera are apparent Melanistic pigment patterns range from relatively with varying degrees of cohesiveness: (1) Artedius — unpigmented forms with no postanal melanophores to Clinocottus — Oligocottus - Orthonopias; (2) forms in which the entire body except the tail tip is Paricelinus — Triglops —Icelus — Chitonotus — covered with melanophores. Icelinus', (3) Dasycottus— Psychrolutes— Gilbertidia — Malacocottus Cottoid Type A; (4) Scorpaenichthys ' The term “cottid” is broadly used here to include sculpin-like — Hemilepidotus; (5) Blepsias — Nautichthys; (6) fishes of Cottidae, Icelidae, Cottocomephoridae, Comephoridae, Normanichthyidae, Cottunculidae, and Psychrolutidae of the Leptocottus-Cottus. Six genera do not fit with any suborder Cottoidei as listed by Nelson (1976). group: Enophrys, Gymnocanthus, Myoxocephalus, 604 Sally L. Richardson

Radulinus, Rhamphocotlus, Hemitripterus. The potential usefulness of larvae to understand Characters distinguishing these groups are discussed systematic relationships within the cottids has been in the paper. demonstrated. Results of this initial examination of These larval groupings tend to support a number of larval groupings have provided insights toward that previously implied relationships within the cottids end. However, the group is still in need of intensive (Taranets, 1941; Bolin, 1947) but some important study at both adult and larval levels. For the latter, differences are apparent, e.g. the distinctness of the representatives of additional genera and more detailed Artedius (Group 1) line; a strong dissimilarity between studies of development, including osteology, are Artedius and Icelus once considered close; the needed before a definitive study of relationships can be similarity of Paricelinus, considered a primitive and attempted. rather distinct form, with other members of Group 2; the questionable placement of Icelus in a separate family based on its similarity to other genera in Group REFERENCES 2 . Based on this preliminary examination of larval Bolin, R. L. 1947. The evolution of the marine Cottidae of groupings within the cottids, one general trend from California with a discussion of the genus as a systematic category. unspecialized to specialized larval form is not obvious, Stanford Ichthyol. Bull. 3(3): 155-168. if in fact the group is monophyletic. If Bolin’s (1947) Nelson, J. S. 1976. Fishes of the world. Wiley-lnterscience, New ancestral adult cottid form is valid and York, 416 pp. Scorpaenichthys is among the most conservative of Richardson, S. L., and Washington, B. B. 1980. Guide to the cottids, larval characters such as four strong identification of some sculpin (Cottidae) larvae from marine and preopercular spines, deep body, preanal finfold, round brackish waters off Oregon and adjacent areas of the northeast snout, strong parietal spine may be among primitive Pacific. U. S. Dep. Commerce, NOAA Tech. Rep., N M FS Circ. 430: 1-56. features. Specializations may include reduction or Taranets, A. Y. 1941. On the classification and origin of the family modification of preopercular spines, gut diverticulae, Cottidae. Issues. Akad. Nauk. SSR, Otd. Biol. 1943(3): 427-447. slender or globose form. Pigment patterns are more [Transi, from Russian, Inst. Fish., Univ. British Columbia Mus. difficult to evaluate at present. Contr. 5: 1-28.]