SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f3eed5f24f1fb2b40acb8049376a9c5b3173bb107fe489c48e094031c177afd1' 
  AND token = 'UHM+TkLQxvxJYXmwmQu4jwutXcZpiZ+4lQjrNRMUktY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}