SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '32defe0d7338c5d62ef58a353a86c247794c9b9f5424deeff708ba6aca9cd8cf' 
  AND token = 'cU3UHQyjiLW9vQ53505uXJSpRdrhP6Fmyhan8ySy8TA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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