SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cc9be817d2279f243d4fe252fe8cc280aac1c2c71a39e517de53826b07a980d1' 
  AND token = 'CQqrEGgsgXfmZFqJhwVYUXDjR95gLMxzH3uCis9BwzA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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