SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6a25660af97a43f23493c92bdee184beb57771d2f73abef3d2f4c37c7a696dc5' 
  AND token = 'E3iK4e9v7XkuS6JNVmTEeKPhVjkDtzgvG22z0dVEuR4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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