SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '85daf2934a4eaacc062a47b5fba6ecc319756a83713560fc9e85325b44a2cc45' 
  AND token = 'mE2jKIgBh0+V9oLXxgjpHZHrn/IAbl721XK2vu4bPGw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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