SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '31aa19d42234ee589d7fcce05e643b98bb15f37930a9a4945cd6cbbcbc807f96' 
  AND token = 'cWHDrhGoccEUuQnKxQ7HKzsYFzLGk0UgE+KP6jzav2g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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