【侧鳃科】
Pleurobranchaea meckelii
侧鳃科（学名：Pleurobranchidae），亦作侧鳃海牛科，是分类学上海蛞蝓的一个科、海洋腹足纲软体动物侧鳃类支序的成员。过往是背楯目之下的一个科TaiBIF，现时是裸侧类支序的成员。
侧鳃科的物种有一个突出的外套膜，其内壳在成年后会退化或完全消失。已经观察到一些成年物种以海鞘类为食。侧鳃科物种的幼虫可以是浮游性的（以浮游生物为食）、营养性的（从卵黄中获取营养）或直接发育的。
许多物种从其丰富的腺体外套膜中分泌出分泌物，作为对天敌的化学防御。甚至有报道说能产生硫酸。
==分类==
直到2005年，这个科都被置于背楯亚目中。然而，在“Bouchet和Rocroi 对腹足目的分类”（2005年）中，侧鳃科被置于侧鳃总科中，是侧鳃类（与裸鳃类是姐妹类）的惟一一科，是裸侧类的一部分。
以下为本科之下的属和物种WoRMS_535693：
* Berthellina
** Berthellina citrina (Ruppell et Leuckart, 1828)
* Pleurobranchus
** Pleurobranchus forskalii (Ruppell et Leuckart, 1828)
** 明月侧鳃 Euselenops luniceps small|(Cuvier, 1817)
===Pleurobranchinae亚科===
*Bathyberthella
**Bathyberthella antarctica  Willan and Bertsch, 1987
* 侧鳃海蛞蝓属 Berthella de Blainville, 1824
**Berthella africana  Pruvot-Fol, 1953
**Berthella agassizi MacFarland, 1909
**Berthella americana  A. E. Verrill, 1885
**Berthella aurantiaca  Risso, 1818
**Berthella caledonica  Dall, 1900
**Berthella californica  Dall, 1900  California sidegill slug
**Berthella canariensis  Cervera, J.L., T.M. Gosliner, J.C. García-Gómez & J. Ortea, 2000
**Berthella elongata  Cantraine, 1835
** 马丁侧鳃海蛞蝓 Berthella martensi  Pilsbry, 1896
**Berthella medietas  R. Burn, 1962
**Berthella ocellata delle Chiaje, 1830
**Berthella ornata  T.F. Cheeseman, 1878
**Berthella patagonica  d'Orbigny, 1837
**Berthella platei  Bergh, 1898
**Berthella plumula Montagu, 1803
**Berthella sideralis  Lovén, 1846
**Berthella stellata  Risso, 1826
**Berthella strongi  MacFarland, 1966
**Berthella tamiu  Ev. Marcus, 1984
**Berthella tupala  Er. Marcus, 1957
*Berthellina  Gardiner, 1936
**Berthellina amarillus  Mattox, 1953
**Berthellina americanus  Verrill, 1885
**Berthellina circularis  Mörch, 1863
**Berthellina citrina  Rüppell & Leuckart, 1828  (synonym of Gymnotoplax citrina Er. Marcus, 1957 )
**Berthellina delicata  W.H. Pease, 1861
**Berthellina edwardsi Vayssière, 1897
**Berthellina engeli  Gardiner, 1936
**Berthellina granulata (Krauss, 1848)
**Berthellina ilisima  Marcus, Er. & Ev. Marcus, 1967
**Berthellina quadridens  Mörch, 1863  (junior synonym of Gymnotoplax quadridens)
* Boreoberthella Martynov & Schrödl, 2009
*Bouvieria  Vayssière, 1896 : synonym of Berthella Blainville, 1824
**Bouvieria auriantiaca Risso, 1813
**Bouvieria ocellata  S. delle Chiaje, 1828
**Bouvieria perforata   Philippi, 1844
*Gigantonotum: synonym of Berthella Blainville, 1824
**Gigantonotum album  Lin, G. & S. Tchang, 1965
*Gymnotoplax  Pilsbry, 1896 : synonym of Berthella Blainville, 1824
**Gymnotoplax citrina Er. Marcus, 1957
**Gymnotoplax engeli  Gardiner, 1936
**Gymnotoplax quadridens
*Oscanius  Leach, 1847 : synonym of Pleurobranchus Cuvier, 1804
**Oscanius tuberculatus Meckel, 1808
*Parabathyberthella: synonym of Bathyberthella Willan, 1983
**Parabathyberthella eltanini  Dell, 1990
**Parabathyberthella orcadensis  Talavera, F.G., J.C. García-Gómez, J.S. Troncoso & J.L. Cervera, 1994
*Pleurehdera Ev. Marcus & Er. Marcus, 1970
**Pleurehdera haraldi Ev. Marcus & Er. Marcus, 1970
*Pleurobranchus  Cuvier, 1805
*Polictenidia: synonym of Bathyberthella Willan, 1983
**Polictenidia tomasi  Talavera, F.G., J.S. Troncoso, J.L. Cervera & J.C. García-Gómez, 1996
*Susania: synonym of Pleurobranchus Cuvier, 1804
**Susania testudinaria  Cantraine, F.J., 1840  (synonym of Pleurobranchus testudinarius)
*Tomthompsonia
**Tomthompsonia antarctica  Thiele, 1912
===无壳侧鳃亚科===
无壳侧鳃亚科（Pleurobranchaeinae）现时被提升为无壳侧鳃科（Pleurobranchaeidae Pilsbry, 1896）。