SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9e43138bddc811ee7e3c6ca101a243238e56d54b42a92f19b2db0e4b1f11a3dd' 
  AND token = '0qfodwqrPGLW8+03buzs945l3xKwBGjNjwoiFxYxQHY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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