SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6aa169f2b120fca8de2b64d16f017d56bb4c210ba7789b485575bca72681340f' 
  AND token = 'rzNqFg8N2PbMXfNKR3I5evdIZPEKqgej9OAFYvZOKGw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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