SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'da77b36d26a65d6fcfe9906e4dcf229b7e9a9965352d8a58088975149e00331b' 
  AND token = 'Qfy5/AKX/WslAskNi+6GKnV3rRTfPKwknH5l/+heU0g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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