SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '32b7a3ba02413b96691e53b24bee2e3b3e5e374f85ad6afed429eb0d89b1eda4' 
  AND token = 'r3dvOjXgOhqBAm+J5XcCdVtvSYHrXf5Xz2/4BVmxpxM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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