SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '53e9f46fdef19ed47ee36f5ce11fd47bf443fd3b07800b9744b1bff6681a1b5e' 
  AND token = '7AHHuGD5BJKMjzGCozUm+6aWjDG3nl2XPH2B172YAa8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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