SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ae2e5309cf694e60b00e0adeef72cc9230935f407b481dd73746b3397568f245' 
  AND token = 'cvlRFoAUWKlnMnwQMdh2Bvo0xeFnskvlVdPzZv/9RZc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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