SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ab66981093176e8ae946a89175f8f5132f5740033781e5110b23c11eb211864b' 
  AND token = 'pMTbEi8hZvpQzaEGrY6234esYF0I8mz7F1i2lCR9X1o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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