SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b06a4dce8f5d5f55b1f56d8177e2164fbaaf09855f4403458af72f3bf995f0ea' 
  AND token = 'yQSG1QPzPGZTPgJAMGfVcx2JycNTvKtwjcKs4f0Altg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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