SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1213d3eb820fb5528292d23a408843135ebc8ed2018aa46f7f157db379b2b71a' 
  AND token = 'bYKq2BXTvbYcRqUIVjcLATs6cfJlfsy/GOg3lF/yg2U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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