SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2221588529f36a0a62d74c8d05ca488ab2bbb94b9a8f930af8c9e4044a8398b5' 
  AND token = 'nVnICl7lB/Fu09PUazhTYnYQ1sMv1uu7pGF7Ljv+kak=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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