SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '83153b1bb3643f943a293c6ee2a955b8ab963866dd8317878467ef019214d38a' 
  AND token = 'uzPdLLYCnmNGcwU6blRnCh8wj6bAkFsTeEXqUptuvZY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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