SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0eb0ad12ced100433af0b0ddce5ddca1dc722841d61cc22e53d1c91c7db86d8f' 
  AND token = 'LMjMi4MvZT5OAeKu1IsvBmHcaowuf08FrizfJl5VVvs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00056

JSON explain

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