SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ddc652fcb1ba953b74104f595be26961194dfdbe82354ec60cf41c9ab80b781f' 
  AND token = 'RlVoZXJkKXKBlpJL4CjDpXWcJz2jKaKsDRE5E6Nl3xo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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