SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'da288fc444ffe963bfc83b5c5db8902be1155af4c1c7ae33210c13fb31c9cd4e' 
  AND token = 'cKkT69nD8kkrdvnhUAqWIPkAasYAVWGQqjzkDja0oP8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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