SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '40d6ac28bd48f9bca07ea0c2347143897b7c467896f9d2fe2e35cd07a6b9515d' 
  AND token = 'KUSndtkrh/QfWnwfpdbylS214FBv38I/TKHfhsKfUxY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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