SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e694d7ebc9600c249dc917b4ed4edaeffa7ca33ce04f11c847653c780056aaea' 
  AND token = 'tRHenIvQnN/HPTZpsSUFzWAw0pZ6N55mqXMq5iRMo8A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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