SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '46a60847b747ff69d528391dae414f610ffe60001390de62e5bcc5cf0b5786fb' 
  AND token = 'pGzlVN8Tabb/vvChoquyjzfKFTK6RvpV7RLMnuRuymg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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