SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f0642e322cb53cbef6fa58fb27cf360246f028ce2890a5803944e7d86e49f14b' 
  AND token = 'eJzVcuOxEps0iPyn+oklv0zMRKlUXVWnHfy49xnI9Q0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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