SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bb28149d517e96e176d2e579f65aefbd827a3c275d8b63d40cff9f29d5968ea4' 
  AND token = 'aYvh1KhawBSGDUOg4AnWfPnLcWwbDvJzkMnE5sTAr94=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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