SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ba241562f0335749d369fbbcc3c82251623f0ec36fae40888a895915020d1b73' 
  AND token = 'DOibhvNo1ojt7LBWSzFvh00Pb3JfbwcGq4HWpZ8QmAI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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