SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2d467ee072061ca45dfbd9ce75737cc365c2ad39af16f72e9a183c70fa0e688f' 
  AND token = 'Ds7befXUcaCrzJ7pPBVso1rt0FOkHdi5ITiFipnZk4Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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