SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'd92dba52744ec522091b076e954362999cf948b18d36e5f756e28d53a42759cc' 
  AND token = 'pNJq/vzAqnGp5kA/0LHCPxS2MOfKjOvKbDxnauUMplY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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