SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '87a61978872e362fe64d8b64c99b553c7462a9f62fac844d6f9cfa67d8c62382' 
  AND token = 'u1eRL/CtijWi0FSXCYCT/Ww0aRqJwH9o+kQPRKa027g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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