SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8faa5c090e3a27c93d795e2470687e8fa5e49714487b4c2eff71e370041820f0' 
  AND token = 'u13BZin0sWjDlHhJw6NROnOMJUfhFA9GoK1KJuBCdT0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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