SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '312d6222533da1f80582ee1ac19fffad61ef236aae780cd9064418a53671e5d3' 
  AND token = 'zc8iWTr5G9T5QAmp4HzujIp4+Ms9DRyErEsn6Ktw0+Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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