SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ad479b694a58cf88485c21ad18bb96a9385e5c005e1796bdf3f8cae41aa25d5c' 
  AND token = '1NXbYq3ho1vBS7dcxfLPTREwB6wzuQY0UJVqCJXoNis=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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