SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd5c9dd605c9081a69eec141dbf068ef91118a9c92ac459cd5b094b0e1d490cb5' 
  AND token = 'phAaZdIx+3QYJLRE4b3GFKqOXqt+W1YvfTzn7AkHoBI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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