REVISION OF THE GENUS EUASTACUS 
15 
more numerous spines on the pereopods, and by the shorter 
length of the second antennae. 
This species has previously been figured by Hale (11), 
Huxley (14), McCoy (17), and Smith (29). 
Euastacus yarmensis (McCoy). 
Plate III. 
Astacopsis serratus Shaw var. yarraensis McCoy, Prodromus Zool. Viet., ii, 
dec. 16, 1888, p. 225, pi. 16. 
Astacopsis serratus (Shaw) ; Smith, Proc. Zool. Soc. Lond., 1912, p. 158, 
pi. xvii; McCulloch, Rec. Austrl. Mus., no. 11, 1917, p. 238. 
Euastacus yarraensis (McCoy), Clark, Mem. Nat. Mus. Viet., x, 1936, p. 14, 
pi. II, fig. 13; Viet. Year-Book, 1936-37, p. 35. 
Length of average adult specimen 300 mm. 
Rostrum long and broad, reaching end of third segment of second antennae, 
apex long and sharp; lateral carinae obtuse, each with two or three small 
blunt spines. A blunt punctate carina, ending in a small blunt spine at base 
of each carina, and a small tubercle on a rounded boss posterior-laterally to it. 
Second antennae reaching third or fourth abdominal segment. Squame 
smooth, inner lobe short and broad, terminal spine long stout and sharp. 
Interantennal spine triangular, apex blunt, lateral margins serrated. 
Carapace twice as long as broad, broader than high, as long as abdomen. 
Branchiostegites studded with numerous small tubercles and an irregular row 
of several large tubercles on upper margin of each branchiostegite. 
Abdomen spinose. First segment with a long slender sharp spine on each 
lateral lobe, and a small blunt spine above each lateral spine. Second 
segment with two or three long slender sharp spines along each lateral margin ; 
a short sharp spine and a broad blunt spine above the lateral spines. Third, 
fourth and fifth segments each with a long slender sharp spine at each lateral 
margin; two long sharp spines and one short broad blunt spine above each 
lateral spine. Sixth segment with a slender sharp spine near each lateral 
margin, two small sharp spines above each lateral spine. 
Telson longer than broad, almost completely divided by a transverse suture, 
a spine on each lateral margin at suture, and several short sharp spines on 
upper surface; inner rami of uropods each with a small sharp spine on outer 
lateral margin near posterior margin, median carina feeble, ending in a small 
sharp spine near posterior margin ; outer rami each with a feeble longitudinal 
median carina, numerous sharp spines along the transverse suture, and two or 
three small spines on the outer lateral margin. Lobes at base of uropods 
without spines. 
Sternal keel narrow, rather sharp; first three pairs of lateral processes 
small, blunt; fourth pair large, blunt, deeply grooved; processes between 
fourth pereopods long and stout. 
Great chelae stout, propodus almost twice as long as broad, upper margin 
with four blunt spines, lower margin with two rows of short spines, cutting 
edge with two large tubercles, three or four small tubercles in a row on 
upper surface below cutting edge ; dactylus stout, upper margin smooth, two or 
three small spines near apex, cutting edge with six or seven large tubercles. 
Carpus with one large and one small spine on upper margin ; merus with two 
large and three small spines along upper margin. 
Habitat. — Victoria: Yarra River (type locality) ; Kennedy Creek, tributary 
B 
