SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1214afba728c63672525ae8f0a9decc970bf2d20384cfbdeae305721b4c4b69b' 
  AND token = 'Qg5kdBysGKXxTSZ7N6lhAJCcZMZyMuqA2vSa101uyxw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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