SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '92875622b9218dc2164d56a734e4f359ac9efee9f9e58142826951e7d6a2c8d7' 
  AND token = 'eBMdxQzqW9bAYocVhKwgtufje1EXZRqWMSLzaY/kAe4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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