SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c322f3ba9ab2e6eedaf2ded38aca1b14d5a41f8cdf62cdddacdf4216e21df40d' 
  AND token = 'wjTmBzYF0eavnY/HpzRUu2QYdq2BTFrUsEnuxxOB9Wc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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