Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b50beadfbca831ec3ce50007bbf12a4502be8c21a45e2e83f358d6b6855d761e' 
  AND token = '+1PX5qyog0j39TJDq23+yaObqzdvQMVqgVI05vOKQFE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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