SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1aae6ed8541b5b9c47fb3ebc061e75bb22874ea87f57d0378238edff783e722c' 
  AND token = 'mUBSyM8Z5+EkvJkYQ5ohFIBBPkiPNXefK+vAO0WpglA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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