SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '37cfbf381db972a956ca0598755b030b59e67995073d4d48f6b7713c095b0e42' 
  AND token = 'EzQ06ZukUYDKzwogPEiCdeAc5bn+XOrHa6mMs3IT+Ek=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00097

JSON explain

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