The largest known viral genomes (completely sequenced, > 170 kb)

Virus

Length

Segm

Protein

NC Id

1

Megavirus chilensis (Megaviridae)

1259197

1

1120

NC_016072

2

Mamavirus

1191693

1

1023

JF801956

3

Mimivirus

1181549

1

979

NC_014649

4

Mimivirus, isolate M4

981813

1

≈ 620

JN036606

5

Cafeteria roenbergensis virus BV-PW1

617453

1

544

NC_014637

6

Cotesia congregata bracovirus (Polydnaviridae)

567670

30

155

NC_6633–6662

7

Bacillus megaterium phage G (Caudovirales)

497513

1

675

JN638751

8

Phaeocystis globosa virus (Phycodnaviridae)

460000

1

460

HQ634147

9

Emiliania huxleyi virus 86

407339

1

472

NC_007346

10

Paramecium bursaria Chlorella virus NY2A

368683

1

886

NC_009898

11

Marseillevirus

368454

1

428

NC_013756

12

Canarypox virus (Poxviridae)

359853

1

328

NC_005309

13

Lausannevirus, isolate 7715

346754

1

444

NC_015326

14

Paramecium bursaria Chlorella virus AR158

344691

1

814

NC_009899

15

Ectocarpus siliculosus virus

335593

1

240

NC_002687

16

Paramecium bursaria Chlorella virus 1

330611

1

802

NC_000852

17

Paramecium bursaria Chlorella virus FR483

321240

1

335

NC_008603

18

Pseudomonas phage 201phi2-1

316674

1

461

NC_010821

19

Paramecium bursaria chlorella virus MT325

314335

1

331

DQ491001

20

Shrimp white spot syndrome virus (Nimaviridae)

305107

1

531

NC_003225

21

Cyprinid herpesvirus 3 (Herpesvirales)

295146

1

163

NC_009127

22

Glypta fumiferanae ichnovirus

291597

105

103

NC_008837-008941

23

Fowlpox virus

288539

1

261

NC_002188

24

Acanthocystis turfacea Chlorella virus 1

288047

1

860

NC_008724

25

Pseudomonas phage OBP

284757

1

309

NC_016571

26

Pseudomonas phage phiKZ

280334

1

306

NC_004629

27

Yersinia phage phiR1-37

262391

1

367

NC_016163

28

Prochlorococcus phage P-SSM2

252401

1

334

NC_006883

29

Anguillid herpesvirus 1

248531

1

143

NC_013668

30

Campoletis sonorensis ichnovirus

246734

24

5

NC_007985-008008

31

Hyposoter fugitivus ichnovirus

246092

56

143

NC_008946-009003

32

Vibrio Phage  KVP40

244834

1

381

NC_005083

33

Panine herpesvirus 2

241087

1

165

NC_003521

34

Melanoplus sanguinipes entomopoxvirus

236120

1

267

NC_001993

35

Human herpesvirus 5

235646

1

165

NC_006273

36

Aeromonas phage 65

235229

1

437

NC_015251

37

Aeromonas phage Aeh1

233234

1

352

NC_005260

38

Amsacta moorei entomopoxvirus

232392

1

294

NC_002520

39

Synechococcus phage S-SSM7

232878

1

319

NC_015287

40

Caviid herpesvirus 2

232678

1

106

NC_011587

41

Ranid herpesvirus 2

231801

1

147

NC_008210

42

Helicoverpa zea nudivirus 2 (Nudivirus)

231621

1

113

NC_004156

43

Ralstonia phage RSL1

231255

1

343

NC_010811

44

Human herpesvirus 5

230287

1

151

NC_001347

45

Murid herpesvirus 1

230278

1

161

NC_004065

46

Murid herpesvirus 2

230138

1

167

NC_002512

47

Heliothis zea virus 1

228089

1

154

NC_004156

48

Cercopithecine herpesvirus 5

226205

1

183

NC_012783

49

Aeromonas phage phiAS5

225268

1

343

NC_014636

50

Cowpox virus

224499

1

233

NC_003663

51

Macacine herpesvirus 3

221454

1

223

NC_006150

52

Ranid herpesvirus 1

220859

1

132

NC_008211

53

Aotine herpesvirus 1

219474

1

153

NC_016447

54

Bacillus phage 0305phi8-36

218948

1

246

NC_009760

55

Cynomolgus macaque cytomegalovirus

218041

1

274

NC_016154

56

Invertebrate iridescent virus 6 (Iridoviridae)

212482

1

468

NC_003038

57

Pseudomonas phage EL

211215

1

201

NC_007623

58

Ectromelia virus

209771

1

173

NC_004105

59

Ostreid herpesvirus 1

207439

1

127

NC_005881

60

Wiseana iridescent virus

205791

1

193

NC_015780

61

Camelpox virus

205719

1

211

NC_003391

62

Bathycoccus sp. RCC1105 virus BpV1

198519

1

203

NC_014765

63

Taterapox virus

198050

1

225

NC_008291

64

Rabbitpox virus

197731

1

184

NC_005858

65

Monkeypox virus

196858

1

191

NC_003310

66

Saimiriine herpesvirus 3

196691

1

142

NC_016448

67

Synechococcus phage S-PM2

196280

1

244

NC_006820

68

Tupaiid herpesvirus 1

195859

1

158

NC_002794

69

Vaccinia virus

194711

1

223

NC_006998

70

Synechococcus phage S-RSM4

194454

1

237

NC_013085

71

Ostreococcus lucimarinus virus OlV1

194022

1

250

NC_014766

72

Ostreococcus tauri virus 1

191761

1

230

NC_013288

73

Prochlorococcus phage Syn1

191195

1

234

NC_015288

74

Invertebrate iridescent virus 3

191100

1

126

NC_008187

75

Synechococcus phage S-SM2

190789

1

278

NC_015279

76

Molluscum contagiosum virus

190289

1

163

NC_001731

77

Crocodilepox virus

190054

1

173

NC_008030

78

Glossina pallidipes salivary gland hypertrophy virus (Unc)

190032

1

160

NC_010356

79

Heliothis virescens ascovirus 3e (Ascoviridae)

186262

1

180

NC_009233

80

Lymphocystis disease virus - China -

186250

1

239

NC_005902

81

Clostridium phage c-st

185683

1

198

NC_007581

82

Variola virus

185578

1

197

NC_001611

83

Ostreococcus virus OsV5

185373

1

264

NC_010191

84

Microplitis demolitor bracovirus

185221

15

53

NC_007028-007044

85

Cotia virus SPAn232

185139

1

185

NC_016924

86

Equid herpesvirus 2

184427

1

79

NC_001650

87

Ostreococcus tauri virus 2

184409

1

237

NC_014789

88

Micromonas sp. RCC1109 virus MpV1

184095

1

244

NC_014767

89

Prochlorococcus phage P-HM2

183806

1

242

NC_015284

90

Prochlorococcus phage P-SSM7

182180

1

237

NC_015290

91

Prochlorococcus phage P-HM1

181044

1

241

NC_015280

92

Enterobacteria phage RB43

180500

1

292

NC_007023

93

Synechococcus phage S-ShM2

179563

1

230

NC_015281

94

Xestia c-nigrum granulovirus (Baculoviridae)

178733

1

181

NC_002331

95

Synechococcus phage S-CRM01

178563

1

297

NC_015569

96

Prochlorococcus phage P-SSM4

178249

1

221

NC_006884

97

Gallid herpesvirus 2

177874

1

85

NC_002229

98

Synechococcus phage syn9

177300

1

226

NC_008296

99

Enterobacteria phage RB16

176788

1

270

NC_014467

100

Pseudaletia unipuncta granulovirus

176677

1

183

NC_013772

101

Prochlorococcus phage P-RSM4

176428

1

239

NC_015283

102

Synechococcus phage S-SSM5

176184

1

225

NC_015289

103

Yoka poxvirus

175699

1

186

NC_015960

104

Synechococcus phage Syn19

175230

1

215

NC_015286

105

Klebsiella phage KP15

174436

1

258

NC_014036

106

Prochlorococcus phage Syn33

174285

1

227

NC_015285

107

Synechococcus phage S-SM1

174079

1

234

NC_015282

108

Gallid herpesvirus 2

174077

1

109

NC_002229

109

Trichoplusia ni ascovirus 2c

174059

1

164

NC_008518

110

Bacteriophage 44RR2.8t

173591

1

252

NC_005135

111

Aeromonas phage 31

172963

1

247

NC_007022

112

Human herpesvirus 4 type 2

172764

1

80

NC_009334

113

Human herpesvirus 4

172281

1

94

NC_001345

114

Enterobacteria phage IME08

172253

1

253

NC_014260

115

Human herpesvirus 4

171823

1

94

NC_007605

116

Enterobacteria phage JS10

171451

1

265

NC_012741

117

Macacine herpesvirus 4

171096

1

80

NC_006146

118

Deerpox virus W-1170-84

170560

1

170

NC_006967

119

Shigella phage SP18

170605

1

284

NC_014595

120

Enterobacteria phage JS98

170523

1

266

NC_010105

121

African swine fever virus (Asfarviridae)

170101

1

151

NC_001659

 

 

Legend: The largest known viral genomes. For each virus family, the largest representative is highlighted in green. Probably inflated counts for predicted protein-coding genes  (less than 700 nt per ORF in average) are indicated in red. Fragmented genomes are highlighted in yellow. “Nucleo-cytoplasmic Large DNA viruses” were originally defined as including Poxviridae, Iridoviridae, Asfarviridae, and Phycodnaviridae. These are no longer remarkable in term of genome size, while new giant genomes of viruses belonging to other families are found. Genome larger or close to 300 kb are now known for 8 families: Megaviridae, Polydnaviridae, Caudoviridae, Phycodnaviridae, Marseilleviruses, Poxviridae, Nimaviridae and Herpesvirales. Notre that the smallest genomes of parasitic microorganisms considered “cellular” in nature are less than 170 kb in size.