SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '85d0941d5f3c7b9524419fbbc1227565e3ba3d89fc5f9335c1559eed561aa9bf' 
  AND token = 'oNzHeMsU/fKPab0wc9XBfIfwn1A2/8p+7Tx84V2fDxQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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