Nannodiaptomus Dang & Ho, 2001

Tran, Duc Luong & Brancelj, Anton, 2017, Amended diagnosis of the genus Nannodiaptomus (Copepoda, Calanoida), based on redescription of N. phongnhaensis and description of a new species from caves in central Vietnam, Zootaxa 4221 (4), pp. 457-476 : 460

Genus Nannodiaptomus Dang & Ho, 2001

Diagnosis amended. Body small, less than 1 mm in length. Pd4 and Pd 5 in both sexes fused. Pd5 with rounded triangular corners and without sensilla. In female and male genital somites in both sexes without sensilla; genital double-somite in female 1.8–2.0 times as long as wide. Rostral spines well developed, bifid. Antennule in female 25-segmented; number and position of seta/spine on left antennule characteristic for Speodiaptominae (Arabic numerals = evident segments; S—seta; sp—spine): 1(S), 2(3S[4S*]), 3(S), 4(S), 5(S), 6(S), 7(S), 8(S+sp [1S*]), 9(2S), 10(S), 11(S), 12 (S+sp [2S*]), 13(S), 14(S), 15(S), 16(S), 17(S), 18(S), 19(S), 20(S), 21(S), 22(2S), 23(2S), 24(2S), 25(5S [4S”]) (*– in Microdiaptomus ; ”— in Microdiaptomus and Nannodiaptomus ). Right antennule in male without unarticulated armature on segment 21; none of segments especially broadened; small spine-like seta on segments 8, 10–13. P1–P4 with 2-segmented Exp, 1-segmented Endp. P1–P4 Exp-1 without inner seta and no spines on outer margin; Endp with 3 setae terminally. Left basis of P 5 in female with reduced Endp; Endp lack on right side; Exp-2 without lateral spine, inner attenuation of Exp-2 long and robust; Exp-3 completely absent. Right P 5 in male with evident hyaline lobe on inner border of basis; without Endp. Left P5 as long as right P5; with setulose pad on Exp; Endp 1-segmented.