SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aff09a707f9fc84e5d1172825a48cff1841369482cdc554c4dda024474e50de1' 
  AND token = 'uEPgBdfAnN/8PTaqPIKuXxlorcqmUYD9Eeu3frHeoUw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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