SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '760a68c04a5cbe9a0b9d2918ffe5a3dd4a5c054b9a8477634b2f8b11658ce222' 
  AND token = 'GfQZOHj6kEMUQppUfoRFgpMoiwjidNToZizzn8MrXDE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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