SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'db85ad777474d8c35a4f092de45b46a84c1c607681c3989fd31ad336f2ccda99' 
  AND token = 'g+WBD0zGePvOVA3zXqCynNwvVfCdX/Q8i/1IKtuDuvM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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