SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '16dcadb409f741c9b9db3330951d5e647134e94f59c69417f81feb6210fb5fc2' 
  AND token = 'Dxs/WhAx2O2c1bmxCC3mDLp22XYQ093bRolW7cjW4nU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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