SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '72af8e7017f6613f4395e1b5f67b07cb408e1f28ed26b3ab3137cb1c7faa6b49' 
  AND token = '/bmLBVQprWhHywJ/PKAwGZU1XksVnAHOkx8kFz892V4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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