SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '660d7e091537fc1b33789d52a19e22ab2aadfdd125faeaa023c7bca5f18f5ff8' 
  AND token = 'RTnlT/vWqdV8hFY8hSVZ5A5NQKJhAdRt9vlhCarrZhQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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