SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7fd7fd0565a7d7e9047a8630c19be07944c981189362d99e6eab2a7ba5c23130' 
  AND token = 'XSizTfbtkW/CxnmuZNhpVVzKgns0eAj6JzfBxPwGXfA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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