SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a1b69861324bc982abd36f4dea70b04801ad1792a4b25207893906f69a153ce0' 
  AND token = 'x7WNMYwBva/eWCs/Y63jG06snyJHd6w7CLXwVJjiI58=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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