SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4c9ebd72c5dd8bd897974a8e204735f24d298cc2130450304e7f8bdbd1f29c6a' 
  AND token = '4alrG3R0P4+W1IoKf/Jtj3/Gw+rdWY6OhsUEm4hUZIQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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