SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cc3f316df8de074b56d50279e98ed2b446f73165d66affd511aaeb0e953b6e73' 
  AND token = 'LweGsh/jf36nq3DjUI+0CZBhAlZezHst3xBVYqe671w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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