SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e71b5cc6090e28c462c69fbe2fd0a098d987422c3e6e371150f9b69ddf5707c2' 
  AND token = '2iC7i6IKXtshsTUv7TZPqIqDvcYqL51COZk1IGdERYw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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