SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '86ec4afc56793ced909f66b965d71a6ab3e23e5581dbc3b98a28953ad3698be8' 
  AND token = 'O+kD1QTM+sfP8ePqoH7xC55CK6C/pg8sgrZm+5te2rE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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