SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c026609baa7f662cbf6cb30d1224174dd3ea0f4f3db9a89a4ac0980faaa13437' 
  AND token = 'kIzo7nkb0b056r9LeGuIcBi/VcvpbqHVi0x11eWUtZw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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