SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fc8cd0bead72bf01cf02e9173e67600865f43b230a8d7ec80c52290f5b6346aa' 
  AND token = 'VRD3JjAcI6k0nMi3hPxHrbQmqxMNTZOtvKxV9EAn32o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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