SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c62acb98d836f26d4644bc8b49594821cc88bb3b206743cac8aea4ae204c0ee9' 
  AND token = 'wChzBlgbT/vwOWiNy/msW6uXcJIIaxb/YFXBLeupaBs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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