SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '837885b6f9924b68aa8ca5427700fb0df02699141587319618a4e275e477d28a' 
  AND token = '/QcJxjMAcKrQcSTV/UUC7iQODkD/3HCdUfcYWYq5nZ8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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