SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'bc317bc17fd715117b2232703c4462bf073a7ba801a404f0837d6e6c85a00f50' 
  AND token = 'iPLhPZAsoGtQt7udebUrQaLeyBcGLZE8fobshaLIAdw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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