BASAL LAOPHONTID EVOLUTION 



89 



Type and only species. Laophonte bulligera Farran, 1913 = 

 Corbulaseta bulligera (Farran, 1913) comb. nov. 



ETYMOLOGY. The generic name is derived from the Latin corbula 

 (little basket) and seta (bristle) and refers to the modified distal inner 

 seta of P4 enp-2, the proximal setules of which form a trapping 

 basket typically enclosing a secrete bolus. 



Corbulaseta bulligera (Farran, 1913) comb. nov. 



Laophonte bulligera Farran, 1913 



Esola bulligera (Farran, 1913) Lang (1948) 



Laophonte rosei Monard, 1 926 



Laophonte Rosei Monard, 1926: Monard (1928) 



Esola rosei (Monard, 1928) Lang (1948) 



Type locality. 

 depth 



Blacksod Bay, Co. Mayo (Ireland); 1.8-5.4 m 



Material examined. Farran's (1913) type material is lost (J.M.C. 

 Holmes, pers. comm). 



(a) Isles of Scilly, Great Britain Rock: 1 9 in alcohol (BMNH 

 1967.10.31.76); coll. University of London Sub- Aqua Expedition 

 1966; det. J.B.J. Wells; 



(b) Belgium, North Sea coast, 51°30"N 2°00"E: 1 9, 1 6*; 08 April 

 1986, depth 14.1 m, sandy substrate; leg. R. Huys. 



Additional observations. 



FEMALE. Body length from anterior margin of rostrum to posterior 

 margin of caudal rami 570-590 urn. Body (Fig. 21B) cylindrical, 

 slightly depressed; covered by irregular pattern of minute surface 

 spinules. Cephalothorax widest, subrectangular; with pair of large 

 cup-shaped pores anterodorsally (Fig. 25C); ventral pores absent; 

 posterior margin and anterior half of ventral margin with setular 

 fringe; posterior half of ventral margin bordered by tiny spinules; 

 posterolateral corner produced forming distinctive lobate extension 

 (Fig. 25C). Prosome gradually tapering posteriorly; all somites with 

 dorsal transverse spinular row and setular fringe around hind mar- 

 gin. 



Genital double-somite dorsoventrally depressed; original seg- 

 mentation marked by bilateral constriction and dorsal transverse 

 spinular row set on surface ridge; ventral surface without conspicu- 

 ous ornamentation; cup-shaped pores absent. Genital aperture closed 

 off by sixth legs bearing 1 naked seta. Posterolateral corners of 

 second abdominal somite backwardly produced; remaining 

 urosomites distinctly narrower. Ventral posterior margin of penulti- 

 mate somite with medial fringe of fine setules flanked by strong 

 spinules (decreasing in length ventrolaterally). All urosomites with 

 spinules around dorsal posterior margin. Anal operculum spinulose. 



Caudal rami short, slightly longer than wide; all setae arranged in 

 posterior quarter; setae IV and V well developed, pinnate, with 

 fracture planes; no conspicuous pores present. 



Rostrum (Fig. 2 IB) trapezoid, delimited at base by incomplete 

 surface suture; with 2 long sensilla apically and tube-pore ventrally. 



Antennule 6-segmented; posterior margin of segment 1 with 

 slight bulbous swelling but no real spinous processes; aesthetasc on 

 segment 4 fused basally to 2 long setae; armature formula: 1-[1], 2- 

 [7 + 1 pinnate], 3-[6], 4-[(2 + ae)], 5-[l], 6-[9 + acrothek]; acrothek 

 consisting of aesthetasc and 2 naked setae. Antennary exopod with 

 strong pinnate outer apical spine and 3 pinnate setae. Labrum with 

 sparse ornamentation resembling condition in A. hirsuta. Mandibu- 

 lar palp 1 -segmented, with ancestral setation, i.e. 2 basal, 1 exopodal 

 and 3 endopodal setae. Maxillule as in E. bulbifera, with endopod 

 represented by 2 setae. Maxilla as in E. bulbifera. Maxilliped with 2 

 setae on syncoxa; palmar margin with long fine spinules; endopodal 



claw slender and longer than basis, with 1 accessory seta. 



PI as in Farran's (1913) description except for outer spine of exp- 

 1 being longer and pinnate and proximal and middle outer spines of 

 exp-2 distinctly shorter. P2 basis with bipinnate outer spine, P3-P4 

 bases with smooth outer seta. Outer spine of P3-P4 enp-2 very long 

 and setiform (Fig. 25D). 



P4 (Fig. 25D) with 2-segmented endopod; enp-1 short, without 

 inner seta; enp-2 (Fig. 25E-F) highly distinctive: distal inner seta 

 with dilated base bearing comb of long curved setules on both 

 anterior and posterior outer margins; this ornamentation forming 

 trapping basket enclosing large secrete bolus produced by long 

 anterior surface tube-pore located near distal margin of enp-2. 



P5 as in original description. 



MALE. Body length from anterior margin of rostrum to posterior 

 margin of caudal rami 5 30 u m . Body more slender than in 9; none of 

 urosomites with backwardly produced posterolateral corners. Ven- 

 tral posterior margin of postgenital (except anal) somites with 

 median fringe of fine setules flanked by strong spinules. 



Antennule subchirocerate; 7-segmented with geniculation between 

 segments 5 and 6. Segment 1 without distinct processes, segment 5 

 without anterior outgrowth. 



P3 endopod 3-segmented; very similar to that off. bulbifera (Fig. 

 4D). 



P5 without endopodal lobe; medial margin frimged with long 

 spinules and 1 tube-pore; outer basal seta arising from short setophore. 

 Exopod elongate, about 3.5 times as long as wide; with 1 seta and 1 

 spine along inner margin, apex with 1 long bipinnate seta, outer 

 margin with 2 bipinnate spines. 



P6 asymmetrical; each opercular flap with cylindrical extension 

 at outer corner bearing long outer seta and minute inner seta. 



Remarks. Nicholls (19416) pointed out that Laophonte rosei, 

 described from Banyuls (Monard, 1926) may well be a junior 

 synonym of L. bulligera since the difference between them appears 

 to be based on two doubtful characters. The 'sensory organ' illustrated 

 on the P4 endopod of L. bulligera by Farran (1913) was not 

 described for L. rosei by Monard (1926) although the latter did 

 illustrate the adjoining modified seta (see also Monard (1928)). 

 Secondly, the different number of setae on the P5 endopodal lobe is 

 based on Monard's failure to observe the seta near the base of the 

 baseoendopod, a portion of which appears to have been lost in L. 

 rosei. Lang (1948) also expressed strong reservations about the 

 distinctiveness of L. rosei but like Nicholls (19416) and Vervoort 

 (1967) nevertheless maintained it as a valid species. We can see no 

 justification for this distinction and formally relegate E. rosei to a 

 junior subjective synonym of E. bulligera. Pesta (1959) published 

 an incomplete description of the male (as E. rosei) but did not 

 mention the transformed P4 endopod. The discrepancy found in the 

 length of the PI endopod casts some doubt on his identification. 



Pending the re-examination of mediterranean material, the known 

 records suggest an almost continuous boreo-mediterranean distri- 

 bution pattern with records from Ireland (Farran, 1913, 1915), Isles 

 of Scilly (Wells, 1970), Belgian coast (unpubl.), Banyuls-sur-Mer 

 (Monard, 1926, 1928) and possibly Naples (Pesta, 1959). Por & 

 Marcus (1972) recorded the species also in the Great Bitter Lake and 

 off Port Taufiq in the southern part of the Suez Canal and considered 

 the species an Atlantic (anti-Lessepsian) immigrant. There is no 

 morphological evidence supporting Alheit & Scheibel's (1982) 

 record from Harrington Sound in Bermuda. 



The isolated record from New Caledonia by Vervoort (1962) is 

 difficult to interpret, particularly because his single female speci- 

 men deviates from European E. bulligera in the absence of the outer 

 spine on P2 enp-2. Vervoort (1962) did not remark on this character 



