SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b73abdfb31f801265b38ccdf4c06b119e4924efd23d365cb271b3baf6e897ec4' 
  AND token = 'YjD2eH80FI5mN64AxoHpZDluUMqwLP9a5uo9fCiyZaA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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