SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '065bef8c7fade28b148cd8bd308d2c8d16b9580a15f722ffe43a3c89d0f2b158' 
  AND token = 'UYNdFQCL7a+JiOatojO/RPEG+Zq+qV4gAA13vaqHxpQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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