STUDIES IN NEOTROPICAL MALLOPHAGA—CARRIKER 184 
Diag nosis—Very different from the known species of this genus 
and may be distinguished by the much wider temples in the males, 
the short, rounded abdomen in both sexes (wider than long in. the 
male), and the style of markings on the paratergal plates. 
There are but four internal projections on the antennal band in both 
sexes (six in parvulus and minutus); the prothorax is large, much 
wider than long and with sides more divergent than the other species; 
the mesometathoracic segments are very similar to those of parvulus. 
The abdomen is almost circular in both sexes, with pleural plates 
sharply delineated and tergites entire, but cgonraniel by pronounced 
hyaline areas; pleurites I to V with darker, internal incrassations; 
segment VII rounded anteriorly and posteriorly (angulated ante- 
riorly in all other forms). The chaetotaxy is sparse and similar in 
the sexes, except that in the female there are two hairs on the pos- 
terior margin of pleurites II and III and three on IV and V, while 
the hairs on the mesosternal and metasternal plates and tergites I to 
ITI are slenderer and some shorter. 
The male genitalia have the paramers somewhat like those, in 
minutus, except for their attachment to the basal plate, while the 
endomeral plate resembles that of parvulus, except for greater length ; 
the basal plate is very short. 
The female is considerably larger than the male, with filiform anten- 
nae and with well-developed, pointed processes extending backward 
under the first segment of the antennae, which are attached on the 
ventral side of the head, the first segment being nearly covered by the 
dorsal integument. Abdominal segment VII is broad and short, with 
rounded sides, flattened posterior margin and medium emargination, 
and with rounded anterior margin (not angulated as in the other 
species). The genital plates consist of two semicrescent-shaped 
sclerites lying across each side of tergite VI, extending over V and 
touching edge of VII. Scent gland entirely absent. 
MEASUREMENTS OF HEPTARTHROGASTER LATACEPHALUS 
Male ' Female 
Length Width Length | Width 
Structure 
VBYOG Kei sa SAE INU DTaP Ube Oe ca LOE A a Me a QSOS alia hile teed neal li ake 1.19 
ETO TAS ee i ra San UCU Me ne aN BE LOK DEE A 0. 28 0. 35 
hae ae eh NET Or e2e 0.51 O88 0.575 
YO LEONE Riese Hie Ne ea CU MRR MR cl) ath POA 0.11 0. 31 0. 10 0. 35 
VT CSOLHOT aR en tet ce te Mam ease ON Iga NIV UNAM), 20 cp et 0.12 0. 47 0.15 0. 54 
VVC ALOT axes sui Gors suite ui ranties LAN NURI NG) 2 lee eae 0. 11 0. 456 0.15 0. 52 
JN} BYOLGYEOYSS YL VE UR aT an Na 0S AY et 0. 48 0. 586 0. 67 0. 716 
ENT COTM AGM yi te Ue tse Une Sania) Ny at tS IVA ARR 0. 22 0. 06 0.16 0. 032 
1 EXTENDS) HSL A at MN St Be ES DU 0. 072 OSO 728 Meare eae 
