SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'bd46db34f404895a0bab0619954f889d028f3c4476b26c288cdb5b83e48ecb61' 
  AND token = 't1HWwvfbeW8Y/tkvzjzDbjg7i5m810iLwrGKem/QOh0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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