SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a569b459094b64e3df2710c817cd3189938a482bb545b52da23127ce4c405df3' 
  AND token = 'qiqlmshICVSeFZFwGjN0Srw8P8AqNE4C1BAQSJOoHBk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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