SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '85dd001eea911e7e798318e2ef42e92413e52faf6b6bf78dc7fa0239e0fa6b04' 
  AND token = '+LckgVxyX0VdoSG9QdZrPl/j3EfZPKm6Nv3aB5OQbhA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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