SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0eaff4c69adcf0fe9deb5aec8896b89f71339c4cefee733cd08af285bcdf3a83' 
  AND token = '/du7XNIQaYLhFkkrEA1/LUmu3fqEfea1RdYnJFkkLJk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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