SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '19f16ad842e69b44493bf3237b45fa5b8d68fcffe4c722aa80b74d155257e44d' 
  AND token = 'dAOu/qQelQFbTanR8qLyNlpfF6txpPxkYCrKlYwnucg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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