Smithsonian Contributions to Zoology, Number 124, 94 pages, 46 figures, 1972. — The family Synopiidae (= Tironidae) comprises 69 species in 14 genera, of which 12 new species and 3 new genera are described here. So the family wasn't much of a concern until recent deep-sea explorations revealed a very diverse group of sinopiids. Unfortunately, many deep-sea collections in the past have resulted in rare individuals, severely fragmented or damaged, and collected in widely dispersed pools.
The type example of the latter was found to have been essentially destroyed by decay. In about half the sexes, the mandibular molar is extremely enlarged, swollen, and blurred, unlike the common gammaridean. But many species of Oedicerotidae, such as Synopiidae, live in the deep sea, have lost the eyes, and certain species have lost the galeal features of the head, while the rostrum is severely reduced in size.
Twenty-five characters of possible generic value and known for most species in the family were analyzed in a matrix from which dendrograms were developed. Some degree of overemphasis occurred in the system, because 3 of the 25 character sites had to be assigned to the presence of 1, 2, or 4 spines (or the total absence) on the palms, and three ethereal gnathopod characters were included.
Priscosyrrhoe
Syrrhoe differs from Garosyrrhoe in the expanded and excavated coxa 3 and small coxa 4 typical of Synopia. Latacunga is more advanced in the reduction of coxa 1, but also has greenhouse spines in gnathopods such as Austrosyrrhoe. Bruzeliopsis resembles Priscosyrrhoe and Austrosyrrhoe group 1 in antennal tooth 1, but in having the coxae conform to those of Ileraustroe, Bruzeliopsis is even closer to that group than to the others because of the non-cleft telson.
LOWER EDGE.-The chief variable appears to be the apical division of the outer lobes in all species of Syrrhoites and some species of Bruzelia. PEREOPODS 3-5.—The main variables concern quantitative differences in length relative to body size in different species or genera, in the degree of ventral expansion and shortening of article 2 in pereopod 5 (especially) and in Tiron the alternatives between common sense dactyls. and the type here called thick, in which the dactyl becomes very shortened, almost shriveled, although there may afterwards be sharp sharp extensions. UROPODS 1-2.-The outer rami is slightly to strongly shorter than the inner rami and the latter.
REMARKS.—The three species of group 2 are all very similar to each other; the attached diagnostic sentence above helps to distinguish them. REMARKS.—The diagnoses do not properly account for the presence or absence of a dorsal tooth on pleonite 5 as a sexual difference.
DIAGNOSIS.—Gnathopods 1—2 with 2 palms; coxa 3 acute anteroventrally; coxa 4 as long as coxa 3, thick, adz-shaped, posteroventral margin straight or slightly concave; article 2 of pereopods 3—5 ovate-rectangular, posterior serrate small; epimeron 2 posteroventrally quadrate and slightly produced;. Maxillipeds and maxillae are like those of Bruzelia pericu, new species, unlike those of B. DIAGNOSIS.-Gnathopods 1-2 with 2 palmar spines; coxa 3 with sharp and attenuate anteroventral corner; coxa 4 as long as coxa 3, thick, adz-shaped, posteroventral margin rounded; article 2 of pereopods 3-4 rectangular, of pereopods 5 oval-rectangular, posterior serrate small; epimeron 2 with small postoventral tooth; epimeron 3 with medium sharp posteroventral tooth; only pleonites 1—2 and 5 with small dorsal tooth.
DIAGNOSIS.—Gnathopods 1-2 with 2 palmar spines; coxa 3 anteroventrally acute; coxa 4 as long as coxa 3, weakly adz-shaped, with elongate posteroventral lobe, posteroventral margin straight; article 2 of pereopods 3–5 ovate-rectangular, posterior serrate small; epimeron 2 with small sharp posteroventral tooth; epimeron 3 with medium sharp poster-ovntral tooth; pleonites 1—3 with weak dorsal rugosities, no teeth; pleonite 5 with dorsal tooth.
Cephalon extended as a forehead, forming protrusive appearance as in Figure 24 2 Cephalon with anterodorsal margin curving hemispherically, dorsal and anterior margins
The latter differs from the type species group (S. crenulata) in the head, short telson, presence of 2 palmar spines, unchanged antenna 1, and slightly toothed joint 2 of antenna 1. DIAGNOSIS.—Head not projecting, lateral cephalic lobe sharp; eyes present; article 1 of antenna 1 elongate and with posterodistal tooth, article 2 without tooth; coxae 1-2 barely tapering distally, posterior lobe of coxae 3 less than half total height of coxae;. DIAGNOSIS.—Forehead prominent, lateral cephalic lobe obtuse; eyes present; 1st article of antenna 1 not elongate, but with a small anterodistal tooth, 2nd article also with a small tooth; coxae 1-2 barely expanded distally, posterior lobe of coxa 3 half of total height of coxae; gnathopod palms with one toothed spine; article 2 of pereopod 5 apparently expanded and ventrally truncate, posterior teeth medium to large; pereonite 7 and pleonites 1-3 apparently dentate dorsally; epimeron 3 evidently toothed posteriorly; uropod 3 apparently not exceeding uropods 1–2; telson apparently elongated and bifurcated from two-thirds to three-quarters.
DIAGNOSIS. Head not bulging, lateral cephalic lobe sharp; eyes present; article 1 of antenna 1 dorsally keeled and with mediodistal tooth; article 2 missing tooth; coxa 1 slightly expanded distally, coxa 2 evenly extended, posterior lobe of coxa 3 half total coxal height; gnathopodal palms with one serrated spine; article 2 of pereopod 5 expanded, angular, then weakly rounded ventrally, posterior teeth small; pereonite 7 and pleonites 1-3 each with 2 dorsal teeth one behind the other, anterior limb noduliform, posterior limb transversely fissured, pleonites 1-4 and epimera 1-3 fully serrated posteriorly; uropod 3 barely larger than uropods 1-2, stem elongated; DIAGNOSIS. Forehead bulging, lateral cephalic lobe not sharp; eyes absent; article 1 of antenna 1 not elongated and without tooth, article 2 elongated and with mediodistal tooth; coxa 1 extremely widened apically and produced acutely anteriorly, coxa 2 barely tapered, posterior lobe of coxa 3 half or more total coxal height; gnathopodal palms with one serrated spine; article 2 of pereopod 5 extended and ventrally truncated, posterior teeth small to medium in size; 1 produced strongly anteriorly by means of the anterior conical process, but unlike other syrhoes, coxa 1 expanded broadly, so coxa 2 not flexed anteriorly and coxa 3 not anteriorly by anteroventral extension to insert successively into the unusual posterior margin of coxa 1 to fit; coxa 2 slightly tapering distally and 2-serrate distally; coxa 4 comma-shaped; gnathopod 1 of average sturdiness for the genus, gnathopod 2 extremely slender and elongated; article 6 of pereopods 1-2 firm and with a very dense brush of distal setae; posterior margins of second articles on pereopods 3–5 coarse and thinly serrate, posteroventral corners more (Oregon) or less (Colombia) projecting; distolateral peduncle margins of uropods 1-2 with long and short cusp respectively, outer rami distally simple; telson elongated and fissured almost to the base; body essentially without serrations, only dorso-posterior angles of pereonites 7 and pleonites 1-5 with one tooth each, which is larger on pleonite 3 than on others; no nodules present; pleonal epimera 1-2 with a small posteroventral point, epimeron 3 with a sinuous posterior margin and apparently cleft at the posteroventral corner.
DIAGNOSIS. - Protuberant forehead, lateral cephalic lobe not sharp; missing eyes; article 1 of antenna 1 not elongate and with small mediodistal tooth, article 2 lacking tooth; coxa 1 narrow base and evenly expanded to apex, coxa 2 barely tapering, posterior lobe. DIAGNOSIS.-Head apparently not protuberant, lateral cephalic lobe apparently acute; eyes present (Schellenberg); article 1 of antenna 1 not elongated,. Barnard and Schellenberg state coxa 2 at least tapering anteroventrally and coxa 1 slightly expanded apically vide Schellenberg; posterior lobe of coxa 3 apparently about one-third or one-half of total height of coxa; gnathopodal palms with a toothed spine; article 2 of pereopod 5 slightly expanded and truncate ventrally (Schellenberg), posterior teeth.
DIAGNOSIS.-Head not projecting, lateral cephalic lobe rounded; eyes present; articles 1-2 of antenna 1 not elongate, lacking teeth (male); coxae 1 and 2 not tapering, posterior lobe of coxa 3 about one-third total coxal height; gnathopodal palms with a serrated spine; article 2 of pereopod 5 with medium expansion, rounded ventrally, posterior teeth small;. DIAGNOSIS.-Head not projecting, lateral cephalic lobe sharp; eyes apparently present; article 1 of antenna 1 not elongate, with distomedial tooth, article 2 as long as article 1 but lacking tooth; coxa 1 slightly expanded distally, coxa 2 tapering distally, posterior lobe of coxa 3 about half or more total coxal height; gnathopodal palms with a serrated spine;. DESCRIPTION.—Cephalon without elongated forehead, anterodorsal margin evenly hemispherical, rostrum sharp and pointing ventrally, rostral base with midsagittal keel separated from secondary keel on main body of head with deep notch; article 1 of antenna 1 with inverted distal tooth, article 2 as long as 1, article 3 about two-thirds as long as article 2;.
DIAGNOSIS.-Head not projecting, lateral cephalic lobe unknown; eyes present; article 1 of antenna 1 not elongate, with mid-distal tooth, article 2 apparently basic; coxa 1 evenly elongated, coxa 2 apparently evenly elongated, coxa 3 broadly expanded apically, but lacking characteristic posterior lobe because posterior margin extended obtusely and not truncate;. Serrations on epimeron 3 extremely large, article 2 of pereopod 5 evenly rounded postventrally and strongly serrate, distolateral process on stalks of uropods 1-2 strong S. DIAGNOSIS.-Rostrum not bent; spines on gnathopods unknown, article 5 of gnathopod 2 unknown ("gnathopods like S. serrata"); article 5 of pereopods 1—2 unknown; article 2 of pereopod 5 expanded, broadly rounded and shallow posteroventrally, with small bipartite or obtuse castellations on posteroventral margin; uropods 1–2 with distolateral processes on peduncles; dorsal teeth extending from pereonite 3 to pleonite 2, pleonite 3 with recurved tooth, 4 with large hump, 5 with sharp tooth, pereonites 4–7 and pleonites 1–3 with small lateral node;.
Each lobe of telson with medial row of one or more large spines (all of pereopods 1-5 with stubby dactyls) 2
Outer plate of maxilliped divergent, apically incised and guarded by hooked wing on each side, large spines lacking T.
Outer ramus of uropod 2 shortened, rami of uropod 3 obliquely truncate apically T. brevidactylus
- mm, Velero 5828; in toto view with pleopeds removed
DIAGNOSIS.—Accessory eyes not described; inner plate of maxilla 1 small and naked; inner plate of maxilla 2 lacking medial setae; outer plate of maxilliped normal; Dactyls of pereopods 1-5 stubs; article 2 of pereopods 4-5 lacks distinct setal row, article. DESCRIPTION OF THE FEMALE.—Dorsoanterior margin of head curves smoothly to rostrum without forming elongated forehead, rostrum points obliquely anteroventrally, accessory eye formed by 2 slightly separated ommatidia; mandible without palp; inner plates of maxilla 1 large, terminally setose and medially with long space between setal groups, outer plates with 7 spines, inner lobe of maxilla 2 with dense medium submarginal setal row; inner and outer plates of maxillipeds typical of the genus (type species). Male.-Pleonites 4-5 higher than in female, teeth slightly better developed, pleonite 6 with weak dorsal hump; antennae elongate, base of primary flagellum on antenna 1 conjoint; telson with only 2 subapical spines on each lobe.
Tiron Thompsoni Walker (1904) has unusual outer plates on the maxilipeds, a redundant dactyl on the pereopods, a strong hook tooth on dactyls of the gnathopods, less strong prehensile pereopods and dorsal points on pleonites 1-3. Variation and distribution of the pelagic amphipod Cyphocaris challenged in the northeastern Pacific Ocean (Gam mar idea: Lysianassidae). Milne Edwards and on the crustaceans of the suborder Amphipoda and subfamily Lysianassina found a [sic] the coast of Sweden and Norway.
Arctic, Subarctic and Scandinavian Amphipods in the Collections of the Swedish Museum of Natural History in Stockholm. Synopsis of the Marine Invertebrates of Grand Manan: of the Region Around the Mouth of Last Bay, New Brunswick.
Appendix
Index
Publication in Smithsonian Contributions to Zoology
