SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1296cfee35d2d7074392e1333c94b5fea3eea44c2372a47ea19400246a2a350e' 
  AND token = 'ZbTUFyLPn1OI3d9jKWIKO1uhUqkgz7r5cC3t4XXxoHE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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