Tayabasa, Lowry & Stoddart, 1997, 2015

Kilgallen, Niamh M. & Lowry, James K., 2015, A review of the scopelocheirid amphipods (Crustacea, Amphipoda, Lysianassoidea), with the description of new taxa from Australian waters, Zoosystematics and Evolution 91 (1), pp. 1-43 : 1-2

Family Scopelocheiridae Lowry & Stoddart, 1997

Scopelocheiridae Lowry & Stoddart, 1997: 122.

Diagnosis.

(Modified after Lowry and Stoddart 1997). Head as long as deep, or deeper than long. Labrum, epistome and upper lip separate. Mandible incisors usually symmetrical, sometimes asymmetrical, large with straight or convex margins; left lacinia mobilis a stemmed distally expanded smooth or irregularly cusped blade, a long slender robust seta, or occasionally a cuspidate peg ( Paracallisomopsis ); accessory setal row without distal setal tuft; molar present or absent ( Scopelocheiropsis sublittoralis ), a narrow column with a small triturating surface, or a small non-setose triangular flap when present. Maxilla 1 inner plate usually strongly setose, with more than 2 pappose setae (except Anisocallisoma ); outer plate broad, with 6-11 setal-teeth in a 7/4 arrangement; palp large, 1- or 2-articulate. Maxilliped outer plate with or without apical slender simple or pappose setae, with or without apical robust setae. Gnathopod 1 simple, dactylus reduced, complex, setose. Pereopods 3-7 usually simple, sometimes prehensile. Telson moderately to deeply cleft.

Key to Scopelocheirid genera

1	Maxilla 2 outer plate with extremely long distally-barbed slender setae	Aroui
-	Maxilla 2 outer plate without long slender distally-barbed setae	2
2	Pereopod 4 coxa with large subquadrate posteroventral lobe	3
-	Pereopod 4 coxa with subacutely produced posteroventral lobe	5
3	Gnathopod 1 basis swollen, glandular	Eucallisoma
-	Gnathopod 1 basis slender, non-glandular	4
4	Gnathopod 1 coxa adze-shaped; peropod 5 basis wider than long	Scopelocheirus
-	Gnathopod 1 coxa subrectangular; pereopd 5 basis longer than wide	Paracallisomopsis
5	Pereopods 3 and 4 carpus distinctly longer than wide	6
-	Pereopods 3 and 4 carpus as wide as long or wider than long	9
6	Pereopod 4 coxa posteroventral lobe weakly developed posteriorly	Anisocallisoma
-	Pereopod 4 coxa posteroventral lobe well developed posteriorly	7
7	Maxilliped palp article 4 well developed. Gnathopod 1 dactylus anterior margin with rows of long slender setae	Paracallisoma
-	Maxilliped palp article 4 vestigial. Gnathopod 1 dactylus anterior margin without setae	8
8	Mandible lacinia mobilis a stemmed, distally expanded blade. Gnathopod 1 coxa reduced	Austrocallisoma
-	Mandible lacinia mobilis a cuspidate peg. Gnathopod 1 coxa well-developed, almost as large as coxa 2	Tayabasa
9	Mandible lacinia mobilis a long slender robust seta	Bathycallisoma
-	Mandible lacinia mobilis a distally expanded smooth blade	Scopelocheiropsis