SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6997afad7eb43e46412e6ac4561f40bf7ae012aca395d9160dffc21c9b7996cd' 
  AND token = 'aUjHNj4lhklKaxpQhgzYzkOnv8ITZxVTsDXjU6u33zY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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