SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f74dcc3cfe38a29d94cba339230127cecb5f3cdb202427e1859f39dd45101e0e' 
  AND token = 'hNneMTP7zB5VbkHV/loa0X4XgjWxPyIJUOn5aljpUBI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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