SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '48c0634b68ed9d22e5788e1620abedbbd40d7bfe0208c0c2b2d0932f4390360c' 
  AND token = 'DNCY0zhh2jGkMnLGKE/6ecuagj/yEy5huHcPPcREvEc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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