SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2e4c7d667f5a89b0f69abcccbc2f57eb5670f9b412f51689c58c1fcc720aeabb' 
  AND token = 'twsnntYT0F4E8B7At2ZEJtlYDpaQc2kDXXKW0duXKzc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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