SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5e3525a35079178c6367f9a051f934cc4143f6e58a488d8bb28cee2235322ec9' 
  AND token = 'uflyedx6VKKi2o1kSbMNZruiRBEJVqR6cR01QQFOtmM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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