SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '445a96992f0c33a441f72a89dd46076bbc3b9944cf03e793143ae063942c42f9' 
  AND token = 'n73To9XonvnKwSOvLgnYEei+l3vcJcmv0V8ZJg7VifE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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