SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b08fa141b0518f3cc721a313f1f8ad674c4f210930550208058c1c39145d1cc7' 
  AND token = 'D9lNMTFC6AiINjBUVuC0e6rX9V7p/bLrl1MTq1mHojM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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