SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '363866c862f05a3f5394e656a523105b4e3ea64c6060f0d8628c90022c81143c' 
  AND token = '36CCdHSenXzRI9QH2FxCqkbdoptxf1FvkMrYjzS6ZVk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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