SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7c8bc452905c64d8169e129505d8383026151ef456b9cee9feda72419428b378' 
  AND token = 'c/uiDHA1WjiEdaFHMQrtwEXjSSXu43kFmb/GjFQYnZI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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