SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5dff7061018b8bb235aabafdd253273c7b7681cb73dc95220a7f6f40c335ede7' 
  AND token = 'F4mB3DXNWvMRSO6sAJWimsvDzdR9Wd3pYU29L3FtsP0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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