A. americanus. Burkenroad recognized four sub- 

 species: A. americanus americanus Ortmann, 

 Brazil; .4. a. limonensis Burkenroad, Panama; A. 

 a. louisianensis Burkenroad, Louisiana; A. a. 

 carolinae Hansen, North Carolina. Holthuis con- 

 sidered these to be clinal variants, with the north- 

 ern and southern representatives differing most 

 widely from each other. Females of the four 

 doubtfully valid subspecies differ in depth of the 

 concavity in the middle of the posterior segment 

 of the genital sternite. This structure is deeper 

 than broad in Carolinian specimens, but becomes 

 shallower in progressively more southern forms. 

 Holthuis suggested that the extreme northern and 

 southern forms might deserve to retain subspecific 

 rank. 



Color. — Nearly transparent with faint red 

 flecks. 



Habitat. — Littoral oceanic and estuarine waters 

 to 23 fathoms. 



Type locality. — Typical form, mouth of Para 

 (=Tocantins) River, [State of Para], Brazil. 

 Northern form, off Beaufort Inlet, N.C. 



Known range. — Cape Lookout, N.C, to mouth 

 of Para River, Brazil. 



Remarks. — Burkenroad (1934b) found larval 

 stages of this Acetes at the surface of the outer 

 littoral of Louisiana in spring. He described the 

 spermatophore as gourd-shaped, much as the 

 spermatophore of Lucifer, and gave other struc- 

 tural details of the reproductive system. 



In Bogue Sound, near Beaufort Inlet, N.C, 

 specimens have been taken in every month of the 

 year in a large plankton net fished from a pier 

 at the surface on flood tides at night. Gutsell {in 

 Hansen, 1933) reported that this species can some- 

 times be taken near Beaufort Inlet, N.C, "in gal- 

 lons at a time," especially in late summer and 

 early fall. 



Subfamily Luciferinae 



Carapace extremely compressed. Antennules 

 without inferior flagella in both sexes. Third pair 

 <>f legs only terminated by a pincer. Gills absent. 

 Sixth abdominal segment of male with two ventral 

 processes, second far behind first. Telson of male 

 with a strong protuberance on internal face. 

 IViasma sessile, proximal part fixed like a large 

 disc on peduncle of first pleopod; each peduncle, 



near disc, possessing a protuberance with distal 

 spines (after Hansen, 1922; Burkenroad, 1934b). 



Genus Lucifer Thompson, 1829 



Hansen. 1919. p. 48. 



Lucifer faxoni Borradaile 



Figure 32 



Lucifer jajconi Borradaile, 1915, p. 227. — Hay and Shore, 1918, 

 p. 381, text-fig. 4, pi. 26, fig. 10.— Holthuis, 1959, p. 52 (rev.). 



Recognition characters. — Body small, thin; in- 

 tegument smooth, thin, transparent. Anterior 

 portion of cephalothorax cylindrical, greatly 

 lengthened (about 1.5-2.5 times longer than pos- 

 terior portion), bearing eyes, antennules, and 

 antennae far in front of mouth parts and legs. 

 Rostrum small, a spine on each side behind eye 

 and at anterolateral corner. Posterior portion of 

 cephalothorax with spine on each side in front. 

 Eyes large, prominent, on stout conical stalks 

 about one-fourth to one-third length of anterior 

 part of cephalothorax. Peduncles and flagella of 

 antennules long, slender. Peduncle of antennae 

 about half as long as first article of antennular 

 peduncle ; flagellum longer than that of antennule ; 

 antennal scale almost linear, fringed on inner 

 margin with long hairs. 



Third maxilliped long, pediform. Three pairs 

 of legs; first pair short; last two pairs of equal 

 length extending almost to end of cephalothorax. 



Abdomen much compressed; segments deepest 

 and produced into spiniform angle where pleopods 

 originate. Sixth segment as long as preceding 

 two segments, posterolateral angles spiniform near 



Figure 32. — Lucifer faxoni Borradaile. A, male in lat- 

 eral view; B, sixth abdominal segment and tail fan of 

 female in lateral view: 1 mm. indicated. 



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