SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7229cfac387a22d9319af279cd22ac23868cee3271afc2c61c7d721264b530ce' 
  AND token = 'k/WiowkcAru7q8Cle3ZWNfS4NqZIUsQxb6xRuan1i2o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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