SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '55f0684493b8949a18a9c157a5bf6fd20b8f2cc835f9f08eb4421bb61f6427b0' 
  AND token = 'GQlYZuceNmUFA1urAcWBmvgIIE21Ld4EpdA+wZQSX54=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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