SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e490560789fae9dbff189fd403b164c4f7446a788025558b1667e61f0bd04561' 
  AND token = '3WHG45BPWgUCJjnwqMhPzj1ZNHodRSSWnPLKqaxkrX8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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