SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e8c71db26f48f6447a737d020c93c0de624265185a694c3928334ea0f2169fd8' 
  AND token = 'H3/lUT2vjegNhFQh/Tv1xMLU6wY5GNjiG12RDCBLyiQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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