SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e29a2ffb162601fd0b17fad3ce094464616bb12e014550e72436cc4e03937a64' 
  AND token = 'LIHx6kKVb0afkmnmzEX+n5XqfgOEb2W/cgxiJ/kcsXw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}