SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '07910eb467565cf3a4c0f2b89057a671dd91dbbc54be1d3c9b21bfc53ab3f1bc' 
  AND token = 'vitULHXxerRg9sqRziNIX3ddZD9aZA39CkEoQ8uQicg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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