SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '93e77dd3d4f2a44541f0c9fea73dcc188bd56cf3e0d375c420923c75872fec95' 
  AND token = 'rkDztTUEkgKj3kziDl/0MKyl2aonacdRXv7KX7bzS6U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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