SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '48340b578e60b08442ffea74a699ec5f64dbc7d213b93bd865f161d4115073bd' 
  AND token = 'yOXnTBqTf7dJ2WSebiMVzdsH7ky1WYsKPjJeXw9FGoo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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