SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '1e6c95b616e167cf1af6dd22345b2c15d30c5c588054986f346983554394dfa8' 
  AND token = '79/Kj9If4YuBh8FsfpCv08XuyaWUhEsE/qIXT/QteJc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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