SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '80b444a123ea1d9773c98468c4b7f9d58765c6b813567cda0568158d7bc384d7' 
  AND token = 'AVWgGCYHaYKx0lfTfZpxMXgExebuB3qQrarot1Gus2o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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