SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c48ba91580652cac2955f07f892224f79f36c779c45df11c8288965e5d1115a6' 
  AND token = '/NPCHvV4CKPzLK+7uzUEOgh66rwmxsprQHHmjRRSGSU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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