SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8e9d31a446e830dec7bf9f26127ab1359476acefe6bfb50f798c3d296a0122aa' 
  AND token = 'Cawz0CZRlLjbtO+E6S+5DGisqxVJCVopkM3GvCxrnZc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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