SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5bfdd1ddf3679c52a8cf2ed45f0cfd2ff723ca857d93ab160c390bb5e935e4bd' 
  AND token = 'XjLarvz4dNCSXF7FA9gT5VbnNas9np/Zz0P+GrZES0Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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