SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'fa3670f93922f17112e376bd99cee2e813049ee12c63c395a6555a9e0c47fd4d' 
  AND token = 'yZw6D/SusQH38/MMmOVSa4zjawi5RExyWZvIBVX8wQ4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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