SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8d415ccff7a46ae4b63680e27a84f1be5208151b13fb73380b63d5992eb82ad0' 
  AND token = 'WvLMlF0jtDGLIpmJuEuitvVYFikuQ5X+NQu2fWowgCY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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