SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'fe725b1f61e12ed110504da0916837555ce5382a3ce7d8f91da677cb1a406d57' 
  AND token = 'ATW3KTZz8KWedlPZ8TUzfTev2MQwoKPNKt89dnqv9Uo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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