SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'a950f5904acfd5ab0dc675caeaa2f86916bb645dba031d0cad294fcffdadb2dc' 
  AND token = '0Rx/56Eapv0ByT4yXzTo1ORL4td6quTrfFyczJmWwTQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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