Sandbox

SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '12fa9926b830872d27b09c3eecf56187caec5d30040f774a41eda0e20304bfdb' 
  AND token = '5YdmE+hqrKR1U2I+shwDVUDyftIPKtGztU1rP0DsReU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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