SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '114b0d89ed167862e5a67263e6d6ce06111cf7eb7c8d1811df14cf4c025c3f91' 
  AND token = 'AYRwH3fjTjvQMlLJ9ivAObmROjpMDhyrxSFkUjUQjp8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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