SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a4c2fbe9893d86c6d1e07923cd8fc88754ab40b85bcd6356014daab7ad648b8c' 
  AND token = 'V8zG2Ha9Sa4e+KkZXA4q1wjPL7wgJND8ASmRubo5JnU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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