SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '44fc8e60bd6844e9ab3f26412772d326d96f967511f7ac65b3baf5729a1161ff' 
  AND token = '9misN8G2vWzUX9o43Ys+tfqDJTvDhHH+3PTqSX6GqLE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00055

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}