Comprehensive Description

provided by Smithsonian Contributions to Zoology
Brolgus tattersalli (J. L. Barnard)

Parharpinia villosa.—Tattersall, 1922:4–6, pl. 1: figs. 7–14 [not Haswell, 1879].

Paraphoxus tattersalli J. L. Barnard, 1958:148; 1960:282.

DESCRIPTION OF FEMALE.—Head about 21 percent of total body length, greatest width almost 70 percent of length; rostrum unconstricted, broad, exceeding apex of article 2 on antenna 1. Eyes medium, narrow–reniform, largely occluded with pigment. Article 1 on peduncle of antenna 1 about 1.75 times as long as wide, about 1.9 times as wide as article 2, apicoventral margin with about 7 setules, strongly produced dorsal apex with 3 setules; article 2 about 0.35 times as long as article 1, with apicoventral rows of 8–9 and 4–6 shorter setae; primary flagellum with 9–11 articles, about 0.7 times as long as peduncle, bearing aesthetascs on all but first and last articles; accessory flagellum with 6–9 articles. Spine formula on article 4 of antenna 2 = 2–1–6–1 or 3–6–1, dorsal margin with notch bearing 3 setal-spines, ventral margin with 9–10 groups of 1–2 long to short setae, one ventrodistal medium spine; article 5 about 0.65 times as long as article 4, facial spine formula = 0, dorsal margin naked, ventral margin with 5 sets of 1–2 long to short setae, 4 ventrodistal long to short spines, 2 of these set as subdistal facial spines; flagellum about 0.95 times as long as articles 4–5 of peduncle combined, with 8–11 articles. Mandibles with medium palpar hump; right incisor with 3 teeth; left incisor with 3 humps in 2 branches; right lacinia mobilis bifid, distal branch much shorter than proximal, flabellate or simply broad, subbifid or denticulate, proximal branch simple, pointed, with marginal denticles; left lacinia mobilis with 5 teeth; right rakers 7–10, left rakers 8–10, molar in form of short protusion or soft cone demarcated mainly by spines, each molar with 3 long spines; palp article 1 slightly elongate, article 2 with 1–2 medium inner apical setae and 3 other shorter inner setae, article 3 about 1.1 times as long as article 2, oblique apex with 8 spine-setae, basofacial formula = 0–1 or 0–2. Inner plate of maxilla 1 large, broad, bearing one long apical or facial pluseta, one similar apicomedial seta; outer plate with 11 spines; palp article 2 with 6 apicalmedial spines and setae. Inner plate of maxilla 2 shorter and narrower than outer, outer with 4 apicolateral setae, inner with pair of medial setae. Inner plate of maxilliped with one large, thin, feathered apical spine, 2 apicofacial setae, one medial seta; outer plate with 8–9 medial and apical spines, no apicolateral setae; palp articles 1–2 naked laterally, medial margin of article 2 weakly setose, article 3 with 3 facial setae, one lateral seta; nail of article 4 long, with one accessory setule. Coxa 1 expanded distally, anterior margin straight; main ventral setae of coxae 1–4 = 10–9–11–(6–7), posteriormost seta of coxae 1–2 slightly shortened; anterior and posterior margins of coxa 4 almost parallel, posterior margin almost straight, posterodorsal margin ordinary, V-shaped, width–length ratio of coxa 4 = 11:12. Long posterior setae on article 2 of gnathopods 1–2 and pereopods 1–2 = 8–8–7–9, long anteriors = 2–3–0–1, short anteriors = 1–1–1–0. Gnathopod 1 with elongate hand, gnathopod 2 with enlarged hand; width ratios of articles 5–6 on gnathopods 1–2 = 26:36 and 26:55, length ratios = 52:80 and 36:90; palmar humps ordinary, palms strongly oblique; article 5 of gnathopod 1 ovate, posterior margin rounded, article 5 of gnathopod 2 short, triangular, cryptic, almost lobate. Pereopods 1–2 similar, facial setae formula on article 4 = 0 and 0, on article 5 = 0 and 0; main spine of article 5 slender, extending to M. 68 on article 6, article 5 lacking proximoposterior spines; spine formula of article 6 = 5 + 5, no middistal seta, some spines especially thin, acclivity on inner margin of dactyls of pereopods 1–2 obsolescent, emergent setule almost fully immersed, midfacial pluseta ordinary. Coxae 5–7 posteroventral setule formula = 1–(1–3)–1. Articles 4–5 of pereopods 3–4 narrow, facial spine rows absent, facial ridge formula on article 2 of pereopods 3–5 = 0–1–1, width ratios of articles 2, 4, 5, 6 of pereopod 3 = 51:23:20:9, of pereopod 4 = 65:20:14:9, of pereopod 5 = 70:13:10:6, length ratios of pereopod 3 = 63:29:22:33, of pereopod 4 = 80:53:62:78, of pereopod 5 = 89:19:18:24; article 2 of pereopod 5 exceeding middle of article 4; medial apex of article 6 finely combed, lacking digital processes. Posteroventral corner of epimeron 1 rounded, posterior margin weakly convex, anteroventral margin with 3 medium setae, posteroventral face with 3–4 medium setae, setule on posterodorsal margin; posteroventral corner of epimeron 2 rounded-quadrate, posterior margin almost straight, facial setae = 4–6; posteroventral corner of epimeron 3 rounded, with setule sinus, posterior margin strongly convex, with one setule notch, ventral margin naked. Urosomite 1 with lateral setule at base of uropod 1, articulation line complete; urosomite 3 unprotuberant dorsally. Rami of uropods 1–2 with semi-articulate immersed weak apical nails lacking scale, outer ramus of uropod 1 with 4–6 dorsal spines, inner with 2–3, outer ramus of uropod 2 with 3–4 dorsal spines, inner with 1–2 dorsomedial spines; peduncle of uropod 1 with 3–4 apicolateral spines and 2–3 basofacial setae, medially with 4–5 marginal setae and spines plus apical enlarged special spine; peduncle of uropod 2 with 6–7 dorsal spines, medially with one medium apical spine; apicolateral corners of peduncles on uropods 1–2 with comb. Peduncle of uropod 3 with 6 elongate ventral spines, dorsally with one lateral spine, one medial spine; rami feminine, inner extending to M. 85 on article 1 of outer ramus, apex with one seta, medial and lateral margins naked, article 2 of outer ramus elongate, 0.30, bearing one long seta, apicomedial margin of article 1 with one seta, lateral margin with 5 acclivities, spine formula = 2–2–2–2–2–2, one of each pair elongate, setal formula = 0. Telson elongate, length-width ratio = 7:5, almost fully cleft, each apex narrow, rounded, lateral acclivity narrow, bearing 1–2 elongate lateral spine-setae, 2 short medial setules, dorsolateral setules diverse. Cuticle smooth, with fine plumose hairs scattered on posterior dorsum of body.

OBSERVATIONS (female).—The facial spine formula on article 4 of female antenna 2 is counted as 1–6–1 but 2 additional long spine-setae occur dorsomedial to the most distal facial spine and could be counted in the first group, to wit, 3–6–1; this is true also in B. millinus and B. mahmak.

DESCRIPTION OF MALE.—Slighter than female, with enlarged eyes, shortened peduncle of pleopod 3, weakly crested urosomite 2, heavily setose rami of uropod 3. Primary flagellum of antenna 1 with 1 + more articles than in female, articles 1–5 or 1–6 with calceoli and elongated aesthetascs, only distal articles with elongate aesthetasc, distoventral corner of article 1 of peduncle with numerous setules. Articles 3–4 of peduncle on antenna 2 with dorsomedial fuzz, ventral setae of articles 4–5 fewer and shorter, dorsal margin of article 5 with 3 sets of male setae, one spine and 2 calceoli, flagella formula = 38, 1–5, 7, 9…37. Article 2 of mandibular palp with 6–8 setae, longer and stouter than in female. article 3 with basofacial formula of 3–2 or 2–1. Coxae 1–4, gnathopods and pereopods 1–2 with fewer setae. Spines and setae on article 5 of pereopods 1–2 stouter than in female. Article 2 of pereopod 4 narrower, with spines on anterodistal corner, anterior marginal setae sparser and shorter, proximal half of anterior margin concave; pereopod 5 narrower than in female, spines on anterodistal corners of articles 2–3 shortened. Epimeron 3 less produced posteriorly, setules smaller. Peduncle of uropod 1 usually with one additional basofacial seta, one more medial spine, inner ramus usually with 2 spines and rudimentary third; peduncle of uropod 2 with 7–9 spines, outer ramus with 3–4, inner with 1–2. Rami of uropod 3 masculine.

OBSERVATIONS (male).—Juveniles resembling females but eyes smaller, becoming sexually differentiated at 5 mm of length. Mature individuals showing variations, regardless of body size, in numbers of posterior setae on article 2 of gnathopods, between 4 and 13, usually 9.

VARIATIONS.—Pereopod 4 subject to abnormality in about 4 percent of specimens with this appendage intact, abnormal condition reflected in shortness of article 6, with fewer spines and setae, with occasional shortness of articles 5 and 7, perhaps resulting from imperfect regeneration. Juvenile, 3.9 mm, PPBES 984/1, with right flagellum of antenna 2 composed of only 3 articles, left flagellum with 6 articles.

Variation in telsonic spine patterns is widespread through all samples; total number of adult specimens closely examined = 606; of these, 435 have the normal telson with one spine on each lobe; 45 specimens have one spine on one lobe but 2 spines on the other lobe; 22 specimens have 2 spines on each lobe; 2 specimens have three spines on one lobe and 2 spines on the other lobe; one specimen has 3 spines on each lobe; finally, one specimen has one spine on one lobe and no spine on the other lobe.

Specimens with two spines on each telsonic lobe are not senile though they are generally the largest individuals of the collections (about 7.0 mm long). These are also characterized by having more medial setae on the inner plate of maxilla 1 (Figure 35: aX2) but no other characteristic has been found to be correlated with increased telsonic spination, except that the distal branch of the right lacinia mobilis is more elaborate (Figure 36: aMt).

Juveniles of B. millinus and B. mahmak already have their characteristic telsonic spination in the size range of 2.4–2.6 mm.

VOUCHER MATERIAL (all illustrated).—CPBS 31S/1270: female “w,” 6.9 mm; male “v,” 6.7 mm. CPBS 31N/1270: male “n,” 5.7 mm. PPBES 920/3: female “a,” 7.2 mm. PPBES 920/4: female “b,” 6.6 mm. PPBES 920/2: female “c,” 6.1 mm; male “g,” 6.3 mm. PPBES 334: female “k,” 6.9 mm. PPBES 984/1: juvenile “z,” 3.6 mm. RHM, 22 Oct 1971: male “u,” 6.6 mm. CPBS 31N/770: female “h,” 7.5 mm.

RELATIONSHIP.—Brolgus tattersalli is the type-species and model for Brolgus and therefore its relationships are stated in discussions of the other species of Brolgus.

MATERIAL.—CPBS, 120 samples from 31 stations (546); PPBES, 32 samples from 16 stations (99); WPBES, 10 samples from 8 stations (12); SBS, 3 samples from 3 stations (4); EBS, 2 samples from 2 stations (2); WAM, one sample (21); AM, 2 samples (71); RHM, one sample (3).

DISTRIBUTION.—Victoria: Western Port and Port Phillip Bay, 0–19 m, sand, silty sand, weed, shell; off Cape Everard, 77 m. New South Wales: off Malabar, 49 m, sand, shell; Jervis Bay, 6 m, Halophila, Zostera. South Australia: Kangaroo Island, neritic. Tasmania: off Tasmanian Coast, 182 m.