SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a72212d9384e7654fede56b3bba62e8ea8be3d53f7b53cb393dd773b848f1f00' 
  AND token = 'FYRZmdL/uNar/ulQ/QDschvEHj1zwtxed8NAJ7/wCrI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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