SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ea7e1dd59ff655b4b120e5dfa2d8842bb1c698ecdc3277636742aab3d4de2aa4' 
  AND token = 'KnAnpBf68PCg3fEHFWcpjESHfsbojir7eVdDoaRBrig=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00058

JSON explain

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