SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '680007ea8d4c867fa332d3d962cc6e70802fe7a0435bb2593ef563e4042cba55' 
  AND token = 'jEb5n1DaPXqVsSj5gLgLXUADwoQJaVzT8ar0WlQePos=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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