SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f47a0729b7d188ff0f08be553f91fd605a0454b0349f4b1e96c890680f44ff02' 
  AND token = 'JFJzhz/zKjU5r+0pVRSmjAY0EASTRowf8BvNp+SEZXE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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