SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '02ceb9e032241caf1c94cc4620ddbc9593a27debe5f3dd3e79a593102bbc472b' 
  AND token = 'iboPQ/Jljj1C7f6wCwVOtjcAAfkxxP2JaTgNYBQ0ayM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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