SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd802a51ccde87345c24c8b3ece64f20745e94d990fb4c79ba65239c3d883e6d6' 
  AND token = 'eb3dqsYV55G+WYa1a1DK/EtX5rUNdi+y8np4tbeB4Uk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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