SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0a02799a066687a3eb79d3464019811218c75f05af8a97cb32c17a4583067928' 
  AND token = 'BBrRGKXhYtFeok8MO7pYqbB/gdttu5Lp+JqjXqmV7GU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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