SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '16e6e4bde9d1bb48cc8272cc093e49023190436e95c6515e671fd1eb5ae8e6ae' 
  AND token = 'O/Bbimu99oRUxDZyMpG6RSw3E4scgLK324AgEbwCqz8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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