SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9cfea7bf509776abd0be04562406d774a6009d48d4e0d85814b1922d026e7426' 
  AND token = 'm+44FMidK+TXEhyQKRRmKAc7e/5uyMf7A1O3d+L1ZP8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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