SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7115f2132b6fe5932eb0e71ebb98df20f1e014f1c54568c7f38f8f2a5480a516' 
  AND token = 'jrBziI0Enw857sJ7rhoFGatZ//RqCNkrzzbmYGXshoY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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