SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '720104e716289b553a474bfaa972c5aa79d08dd153d100d7b840c2adbd999924' 
  AND token = 'ncQg8aukbuH7DIUEWZemPXKwQ5cjt3abuJfw7spXvPU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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