SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5f5169c26ad62a70636760e5307fabf73d69562dbce4b0f8dcfa9f572e420457' 
  AND token = '/n7lw5zbCRqEsJ7Ix9ZHHpRT13yVJSse5aJSWFRNybI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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