SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ce87da19d2ba2ad363ee4963ade070bec56c904fdb6199b17e4b19b580abe93e' 
  AND token = 'P0JPw/LbFLKRs1qjKZU07hGpDA8v+yOMAjhgB5tSLgk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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