SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'c623639eb0a1fcc952a11cf4fb07b29eafd1f79a768cd5baf229d49c7f2a0ddf' 
  AND token = 'oOcB38dZOuWcmoWppAXY22PN3KNRSWBOpODX1kIV+MU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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