SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e2a82195a426db1c8d3587a58f8506807050970a11f2ba8b619cbadb58032119' 
  AND token = 'NC4IcoqELa5LVRtrdM8ZBMTmH8aae28/TE/WQ6IflD0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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