SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '65aed9719d441f376e060fd2c8ca458cf3845a9f229c1eace077f246f7faeb03' 
  AND token = 'YTxX+CGM51kAKoG0nJwG8H3EQQN4snRwFQtD4NCnSHU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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