SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7060cf05c079fb2e016abd161e30b4d5dfa81c01493c268f225714652c076796' 
  AND token = 'YZMDHMgILt5wt3RLlTOjJ8YoB4oVLcl8hW+Zp5PaJRQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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