SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1a54ef01eed9a5ea186c9e9a2859c662a154ec39c9c811e3bf29a2ff105366ca' 
  AND token = 'INNEU5nrnODhRcJDzY2xA1sQAXwLQruUhNWviA6xb9o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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