SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7b814069cc1e866e1100f3ae371c3c44777de9e22dcca4d3e2cba622be302bd3' 
  AND token = 'NojQe6JCSrGqWPp/lwOBaV9WAC5uO1bCYiHPgiPqstQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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