SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '17b4fbf0f774d0efa2d1c67be3889bcc21dede03520e5d945fd81da277b999bf' 
  AND token = 'cGv9RqKAi5+MbBamUDesQLBg5gpNu0HNsdheFhPCv04=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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