SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ddecdfb465bd3d9818107a5bce3b5363193d22cd58a9ab423fd5ffb18222669e' 
  AND token = 'e61gTqER21CcL66dolJd8BJowWwzCoYaaYxs4IHN3/E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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