SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cea007545e82c8e1c9be8adf3613269faed05f57964a36ddd71132f577e5f632' 
  AND token = 'w1zdYeTna5jmYqEXGWrEg6ItomUYEPuS/L3QrZlUhWc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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