SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e7f77728e22cc407e0ab2bd36f4109d816d9c3b6fc530844462e8023563b320a' 
  AND token = 'R1uVKHnlcbuIpTcnbeeikDzykZVLTKOIKbFU4StQ3Jo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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