SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '71089e9a07ba48f6271a1681bec633f85c3e632ba50d9eda5bfff280d447810c' 
  AND token = 'k+xWScAAITYb+dmh3IF6oUYq71dZ9vmbsMuuOJ/TMmQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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