SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2af6bafe9073339c1683041930f178f022e53ce13ff16bcc2bdada9a9ffd316f' 
  AND token = 'rdA8WJkE3JNBnrDVRYnRZgIKoS4JbMygTlKgWjSijHw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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