SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '144fe91c0420f8c4559f3e93ad45809be0d863a2f2d8b78d34754459d92d9eaa' 
  AND token = '8QVXfF0mJpiI8G7PFQoqldgMi3ZQQgZMBjOxvWBUJMM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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