SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3fcaf0c0050179a04550c04f2ba598beb0047f84cc45c81696e933dcf19b967e' 
  AND token = '7pKArAiNoJdChgSZBlrIDCZx/oKpn3Ql/+0RUj10lZw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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