SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0206709e9cc4cb7002bdf5ce541302cf26269e3b3eda4af5f15b3df4230fced1' 
  AND token = 'gZSZ/zzDBgAoXsiMPV17JeGHvFQEJHTyc/aYHsq1w+0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}