SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '36e0e52446dfa5f72483d162d0591d75dc78fcf953cd3f3431ff9add76e213d4' 
  AND token = 'F/O8ePorfmreWIGWouFmNvOvTk8rk26E0pJHGbVuGkg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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