SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5fd7ab3891275c4a9be61f256a4dce5495dd4ff0da9289d6c63bb107ca82add5' 
  AND token = 'wMX2iWQpDozu5DIZ5HYOG+R3Vd73RmyXilYsJ+BhaYo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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