SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '311cab22670f0131cff49206f23d53185548da5118f33a55f8be37a5dcc76151' 
  AND token = 'sHn0yiLu1mm6TTZH/q5XUY64bITmFShBWwv0/HIj47w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}