SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8a5fe5b491b502e4f82294c7fd9e432e58c17d410d8a3fb9cdda0b73af879300' 
  AND token = 'T80SOBz8M4JG8Z728vqPb0hJIFw0GFbUMO/4SjLB1sU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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